The Keto Diet Is Gaining Popularity, But Is It Safe?

A new twist on extreme weight loss is catching on in some parts of the United States. It’s called the “keto diet.”

People promoting the diet say it uses the body’s own fat burning system to help people lose significant weight in as little as 10 days.

It has also been known to help moderate the symptoms of children with epilepsy, although experts are not quite sure why it works.

Proponents say the diet can produce quick weight loss and provide a person with more energy.

However, critics say the diet is an unhealthy way to lose weight and in some instances it can be downright dangerous.

Read More: What is the “Caveman Diet?” “

What is ketosis?

The “keto” diet is any extremely low- or no-carbohydrate diet that forces the body into a state of ketosis.

Ketosis occurs when people eat a low- or no-carb diet and molecules called ketones build up in their bloodstream.

Low carbohydrate levels cause blood sugar levels to drop and the body begins breaking down fat to use as energy.

Ketosis is actually a mild form of ketoacidosis. Ketoacidosis mostly affects people with type 1 diabetes. In fact, it is the leading cause of death of people with diabetes who are under 24 years of age.

However, many experts say ketosis itself is not necessarily harmful.

Some studies, in fact, suggest that a ketogenic diet is safe for significantly overweight or obese people.

However, other clinical reviews point out that patients on low-carbohydrate diets regain some of their lost weight within a year.

Read More: How Exercise Helps You Lose Weight “

Where it’s helpful

The keto diet was created by Dr. Gianfranco Cappello, an associate professor of surgery at the Sapienza University in Rome, Italy.

He claims great success among thousands of users. In his study, more than 19,000 dieters experienced significant, rapid weight loss, few side effects, and most kept the weight off after a year.

According to the reported results, patients lost an average of 10.2 kilograms, or about 22 pounds, after 2.5 cycles of the keto diet. Cappello concluded that the diet was a successful way for overweight and obese people to lose weight, and the few side effects, such as fatigue, are easily managed.

Bette Klein, a registered dietitian at Cleveland Clinic Children’s Hospital, has used the keto diet for years to help ease the symptoms of children with epilepsy.

She told Healthline it is particularly effective with children with refractory epilepsy who have not responded well to at least two different drug treatments.

Klein said about half of these children who go on the diet see a reduction in the number of seizures they have.

The dietitian said, however, that medical professionals are not sure why the diet works in these cases.

“There is not a clear definition of what is happening,” she said.

Rudy Mawer, a sports nutritionist, has also found some success with the keto type of diet.

He said he uses this low-carb approach with some people who have trouble losing weight. He also has high performing athletes on the plan.

Mawer told Healthline there are a number of benefits to the program.

One benefit is its quick results. People can lose some initial weight rapidly and that, in turn, helps encourage them.

“You can get motivated by this weight loss,” he said.

He added the keto diet is simple in concept. It eliminates a food group, making it easier for people to follow.

He said the diet also makes people feel full despite having fewer calories and it gives them more energy. That’s because, he said, people are giving up their sluggish diet of processed foods. He added the keto diet keeps blood sugar levels stable, which produces a more stable flow of energy.

Mawer notes there are some drawbacks.

He said the diet would not necessarily improve athletic performance, a fact that may discourage some athletes.

He added people need to adhere closely to the program or it will not work.

“It is a very strict diet,” said Mawer. “You have to do everything right.”

Every individual, he notes, is different and will react differently to such a program.

“What’s great for one person can be horrible for another person,” he said.

Read More: Experts Say Obesity is “Stamped In” “

When it’s unhealthy

Critics say the keto-type diets usually work only in the short term and can be unhealthy.

For starters, most of the lost weight is water weight, according to Lisa Cimperman, R.D.N., a clinical dietitian at University Hospitals Case Medical Center in Cleveland, Ohio, and a spokesperson for the Academy of Nutrition and Dietetics.

“Once your body enters ketosis, you also begin to lose muscle, become extremely fatigued, and eventually enter starvation mode. Then it actually becomes even harder to lose weight,” Cimperman told Healthline.

Mawer said he doesn’t believe the keto diet causes muscle loss. He did caution it’s not optimal for someone trying to gain muscle.

Other experts interviewed by Healthline had stronger words of caution.

“Keto diets should only be used under clinical supervision and only for brief periods,” Francine Blinten, R.D., a certified clinical nutritionist and public health consultant in Old Greenwich, Connecticut, told Healthline. “They have worked successfully on some cancer patients in conjunction with chemotherapy to shrink tumors and to reduce seizures among people suffering from epilepsy.”

In the general population, Blinten said a keto diet should only be considered in extreme cases.

“It can do more harm than good. It can damage the heart, which is also a muscle,” she explained.

Anyone with type 2 diabetes can benefit from weight loss and a reduced-carb diet because it will improve insulin sensitivity, Cimperman explained.

“But there are many other ways to do it besides a fad diet that won’t keep weight off long-term,” she said.

Blinten, who has used a keto diet for some cancer patients in specific circumstances, cautioned, “people will do anything to get the weight off.” However, a keto diet will do more harm than good for the majority of patients, especially if they have any underlying kidney or liver issues.

“People are using this for cosmetic reasons, but it’s so extreme that it’s dangerous,” she said.

Read More: Why Severe Anorexia is So Difficult to Treat “

The feeding tube approach

Some have taken the keto diet a step further, using a feeding tube inserted into the esophagus through the nose.

Dieters adhere to a strict 800-calorie high-protein, no-carb diet administered through the tube by a slow-drip pump mechanism. Only black coffee, tea, or water is allowed in addition to the liquid diet.

A Florida doctor, Oliver Di Pietro, has been offering this tube diet to anyone who can pay the $1,500 cost. According to a 2012 local news report, Di Pietro learned of the diet while on a trip to Italy. He insists the keto diet is safe and effective, even for those wanting to shed just a few pounds.

“This is a ridiculous approach to weight loss,” said Cimperman.

With an 800-calorie-a-day diet, “you’re essentially starving yourself,” Cimperman said. “Of course you will drop weight.”

Anything under a 1,200-calorie daily diet is considered a starvation diet and is not meant for long-term weight loss.

Tube feeding is a legitimate tool in a hospital setting, she explained.

“Someone who is on a ventilator, or can’t swallow because of a stroke or cancer, might have to eat this way. But it’s usually used as a last resort,” she said.

“In an otherwise healthy individual it can create serious complications, including infections if the tube gets contaminated, increased sodium levels, and it can cause dehydration and constipation,” Cimperman added. “What would even possess people to want to walk around with a tube up their nose?”

Melinda Hemmelgarn, a registered dietitian in Columbia, Missouri, and host of the Food Sleuth radio show, told Healthline, “It’s crazy to consider sticking a tube down your nose to lose weight. It sounds to me like somebody is making a lot of money on someone else’s vulnerabilities. Just say no to this idea.”

Read More: Doctors Finally Begin to Treat Obesity “

Don’t become weight obsessed

Hemmelgarn advised anyone thinking of going on a fad diet to “keep food in perspective. It’s a gift. It’s how we nourish ourselves and stay well.”

Marketing this diet to brides just plays into our weight-obsessed society, according to Hemmelgarn.

Instead, anyone preparing for marriage should nourish herself well, engage in plenty of physical activity like walking, jogging, or bike riding, and be good to herself by eating fresh, whole, minimally processed organic foods.

There is no magic bullet for long-term weight loss, said Blinten. For long-term weight control, a Mediterranean style diet focused on fruit, vegetables, whole grains, beans, fish, and olive oil, is one that can be healthy for life.

“We fall prey to wacko diets, but the truth is there’s no quick fix,” Blinten said. “Cutting refined carbs and replacing them with fresh fruits, vegetables, and lean protein, cutting processed foods, and avoiding too many additives will keep you healthy in the long term.”

Cimperman said the healthiest approach to weight loss is to set realistic goals and ask yourself if your diet plan is:

  • good for the long term
  • includes exercise
  • meets your long-term health goals.

If the answers are no, then that is a red flag, she cautioned.

Blinten advised dieters not to skip meals because your body goes into overdrive the next time you eat. That can actually cause you to eat more, not less. She suggested eating your largest meal at midday, then having a healthy afternoon snack.

“It keeps your metabolism and insulin levels more regular,” she explained.

Exercise, of course, is also vitally important. Every pound of muscle equals 50 calories burned, so a plan that includes a muscle enhancing regimen will help you reach your goal faster.

Hemmelgarn added, “Stay away from fashion magazines. They make us feel inadequate. If you are even considering this insane approach to weight loss, go for a walk … right now! It’ll clear your head.”

Editor’s note: This story was originally written by Liz Seegart and published on December 19, 2014. It has been updated several times since then.

Is the keto diet a safe option for losing weight?

This is part of Canadian Health and Wellness, a series in which Corus radio stations nationwide dig into health issues facing Canadians with the help of some of today’s most respected diet and exercise practitioners. Read the rest of the series here.

By 2023, an additional 1.7 million Canadians will be obese, according to a 2017 study from the Organization of Economic Co-operation and Development (OECD). The report estimates 25 per cent of the population is currently obese — that’s about 9.35 million people.

With just three years until the OECD milestone, people are attempting to fight the battle of the waistline bulge, and many are exploring the keto diet as an option to lose weight.

A ketogenic diet is rich in proteins and fats, and it usually includes plenty of meats, eggs, sausages, cheeses, fish, nuts, butter, oils, seeds and fibrous vegetables.

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The keto diet forces the body to burn ketones from fat instead of glucose from carbohydrates, and during that transition, a person’s body can experience something called the keto flu. As the name suggests, it leads to symptoms like nausea, vomiting, headaches, constipation, diarrhea and irritability, among others.

LISTEN BELOW: Canadian Health and Wellness — the keto diet

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Tammy Crowley of Welland, Ont., is one of them.

Tammy Crowley/Facebook Tammy Crowley/Facebook

She’s been following the ketogenic diet for two years.

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Crowley says she has lost 35 pounds and kept it off. Over the years, she’s tried everything from diet programs to more drastic measures.

“I don’t want to specifically say any one program,” Crowley says. “Everyone is different, and whatever works for you is great. I just found something that finally worked for me. I’ve actually, through the years, I’ve had gastric bypass (surgery) for losing weight, and yes, that was great in the beginning, but you put it back on.

“It’s not an easy fix. Unless you learn properly what’s good for you, that’s the best way to go,” Crowley continues. “I’m not running any of the other programs down. This just works for me. I’ve never felt better. I’m going to be 60 soon and I have more energy now that when I was in my 20s.”

4:21 Ins and outs of the keto diet Ins and outs of the keto diet

The effectiveness of the keto diet as part of a long-term lifestyle change is still unknown, but there are medical uses for the regimen. For example, the keto diet is being used to help treat children with epilepsy.

Jennifer Fabe, a registered nutritionist with the Division of Pediatric Neurology at McMaster Children’s Hospital, says the therapeutic ketogenic diet has been used as a treatment for epilepsy for nearly a century.

READ MORE: Super Awesome Science Show recap — What going keto can do for you

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However, she stresses, it is customized for each patient and only used when people meet certain medical criteria. Fabe says the diet is monitored regularly for effectiveness, tolerance and side effects at home and by a medical team.

Fabe is also the president of Matthew’s Friends, a charity that specializes in ketogenic dietary therapies for children and adults with drug-resistant epilepsy.

Dr. Andrew Mente, an epidemiologist with the Population Health Research Institute at McMaster University in Hamilton, Ont., says the keto diet can also have benefits for those with Type 2 diabetes.

Dr. Andrew Mente, an epidemiologist with the Population Health Research Institute at McMaster University in Hamilton, Ont. Andrew Mente/ McMaster University

“Conceptually, it is a diet that is high in fat, adequate in protein and very low in carbohydrates,” Mente explains. “And conceptually, this diet would make sense for people with carbohydrate intolerance, i.e. people with Type 2 diabetes, in controlling their glucose levels and possibly even reversing their diabetes.”

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“There is evidence that when people are assigned to a ketogenic diet if they have Type 2 diabetes, they are able to normalize their glucose levels and possibly reverse diabetes,” he adds. “In people from general populations, generally healthy populations without diabetes, the evidence is less clear. So, what we would need going forward is more study to investigate both the effectiveness and safety of a ketogenic diet in general populations.”

6:03 Canada-wide Keto Diet Survey Canada-wide Keto Diet Survey

Mente says the” ketogenic diet is one approach for Type 2 diabetes, but it’s not the only diet for people with Type 2 diabetes. It’s too soon to say what the long-term impacts of the diet will be on both those with Type 2 diabetes and the general population.”

According to Mente, the best idea for those without medical issues requiring a ketogenic diet is to eat a balanced diet.

“A nuanced approached is seldomly promoted. Everybody seems to take an extreme position on a variety of matters, and diet is no different,” Mente says. “For general populations, I would say a nuanced approach is more appropriate going forward until we get the evidence (on the long-term impact of keto) because we want to make recommendations that are evidenced-based.”

But what about using the keto diet for weight loss?

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Dan Tisi, registered dietitian at St. Joseph’s Health Care in Hamilton, says there are some pros and cons to losing weight with the keto diet. If there’s a medical indication there are some benefits, like epilepsy, then the keto diet can have a positive impact. However, for weight loss, Tisi views it as another tool in the toolbox.

“With ketogenics having an emphasis on certain fats and proteins, people need to be aware of the nutrition that may be missing if they are on keto,” Tisi says.

0:42 Alcoholic Drinks You Can Have On The Keto Diet Alcoholic Drinks You Can Have On The Keto Diet

“A lot of people will have to do supplementation of some kind with higher-quality supplements because there tends to be a B vitamin deficiency. Electrolytes are the most common thing that’s missing, usually.

“They are also responsible for things like the keto flu that people experience in the beginning, especially the electrolytes part, and magnesium has to be added to that as well. Although, most North Americans are already deficient in magnesium,” Tisi explains.

“It’s best if you are going ahead with keto to do it with the assistance of someone that can really assess your situation and help you determine if this is the tool you should be reaching for.”

For someone like Crowley, who has struggled with weight issues for most of her life, she is not willing to easily let go of something that has worked.

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She says she is aware that some cardiologists have concerns about keto’s emphasis on full fat and high protein, and so does she. Crowley’s father died at 51 from a heart attack, and she says that plays on her mind. She says she did a lot of research before starting keto, and Crowley is willing to shoulder the medical risk.

“I’d rather feel as good as I feel right now and only live another five years than live another 10 years and feel like crap.”

© 2020 Global News, a division of Corus Entertainment Inc.

Is the Keto Diet Safe? The Real Risks and Rewards of Going Ultra-Low Carb

The rise of the keto diet is hard to overlook. From keto cruises to keto-friendly product lines from food manufacturers, it seems like everyone knows someone who has embraced the keto lifestyle.

With such a boom in popularity, many dieters are turning to the internet and social media for keto inspiration. However, there can be conflicting and confusing information about what this diet actually entails, which leaves some people asking, “what actually is the keto diet—and is it safe?”

What is the keto diet?

For starters, the keto diet is more than just eating unlimited amounts of bacon, eggs, and cheese—despite what some Instagram accounts would have you believe. Keto, also known as the ketogenic diet, is a way of eating that allows the dieter to enter a state of ketosis. When you are in ketosis, your body is breaking down stored fat into molecules called ketones that are released into your bloodstream and flushed out in your urine. Ketosis occurs when your body shifts from burning sugar and carbohydrates to stored fat.

In order to get into this metabolic state, the diet consists of high-fat and very low-carb foods. Cedrina Calder, MD, a preventative medicine doctor based in Nashville, explains that most people in ketosis aim to stay under 20 to 50 grams of net carbs total for the day, though the specific carb tolerance varies from person to person based on a number of factors, including activity level. When calculating net carbs, take the total carb count and subtract out the quantity of fiber and sugar alcohols, as those do not have the same impact on blood sugar as other carbs.

For reference, one medium apple has more than 20 net carbs, which would top out the daily limit for many keto-ers, making ketosis difficult to maintain.

“This diet is very hard to sustain on a long-term basis for the average person,” said Dr. Calder. “For the average patient, I advise them to choose a healthy pattern of eating that they can sustain rather than focus on a temporary diet.”

RELATED: No-sugar-added recipes you’ll actually look forward to eating.

Keto weight loss results can be striking and quick

With so many restrictions, it can seem surprising that keto has gained as much traction as it has. Like many recent phenomena, it all goes back to one cause: Social media.

The boom of Instagram, blogs, and other photo-sharing sites has led to more transformation pictures circulating than seemingly ever before. And the keto diet is a prime candidate for producing noticeable results quickly, making it a staple for the popular Instagram hashtag #TransformationTuesday.

“Recently, more and more people are inquiring about the keto diet—not necessarily for a long-term solution, but just to jumpstart their weight loss journey,” said Gabrielle Mancella, RD, who says that at least one-third of her daily patients inquire about going keto.

When you enter ketosis, the switch to burning stored fat creates a diuretic effect, making people lose water weight quickly compared to other methods of dieting. This can make progress look and feel quick at first.

How to get into ketosis

As you enter a state of ketosis, many people experience symptoms known as the “keto flu.” While not a real flu, the transition period can cause headaches, nausea, weakness, muscle cramps, difficulty concentrating, constipation, or diarrhea. These symptoms can be caused by dehydration, sugar withdrawals, or an imbalance of electrolytes—all common effects of switching to the ultra-low-carb diet.

For many people, the keto flu is enough to convince them to give up on this way of eating. But, if you stick it out, the flu symptoms typically subside in about a week. Dieters can avoid, or lessen the symptoms of, the keto flu by drinking enough water, seeking out electrolytes, and cutting back on their carb intake gradually.

Once in a sustained state of ketosis, many dieters report enhanced mental clarity and overall improved wellbeing, in addition to weight loss. However, there hasn’t been a great deal of research done yet to determine if these results are an inherent trait of the diet. Dr. Calder said more research is needed to understand the long-term effects of the keto diet.

To check if you are in ketosis, strips from the drug store can detect the presence of ketones in urine.

The downsides of going keto

While the weight loss can be quick, the keto diet also has some potentially serious drawbacks.

“Being in a state of ketosis can be dangerous for people with kidney disease or diabetes, especially type 1 diabetes,” Dr. Calder said. “I also would not recommend it for individuals with an unhealthy relationship with food. Restrictive diets can worsen this relationship.”

Because success on keto is dependent on cutting out foods that don’t fit into the ultra-low-carb diet, this is not a diet made for people who like frequent cheat days or little daily indulgences, Mancella explains. After eating enough carbs that your body exits ketosis, the whole process has to begin again to get back into the fat-burning state.

“This puts immense strain on the body, and, in turn, is contraindicative to weight loss goals,” Mancella says. “The brain’s main source of energy are carbohydrates, and when we limit this, we are in turn affecting all of our other body processes.”

Although she said that in healthy adults keto is generally safe because the body is able to self-regulate ketone levels by flushing the excess through urine, Mancella added that dieters should approach keto with caution.

“If not done right, this diet can cause havoc on our bodies,” she says. “As a society, we have turned to a culture of restriction and extremes in order to obtain unrealistic beauty and aesthetic standards without considering the long-term consequences.”

Knowing the restrictive nature, some people turn to the keto diet as a quick fix before an event that they want to drop a few pounds for quickly. Even that, however, can have some unintended consequences.

“Anyone starting a keto diet should be aware that once they stop the diet, they are likely to regain weight if they do not transition to a healthy diet,” Dr. Calder said.

What do you eat on a keto diet?

The keto diet itself doesn’t have any required meals. The only goal is to stay under your allotted net carbs each day, so there is a lot of variation in how people choose to go about following the diet.

Generally, commonly eaten keto diet foods include meat, eggs, full-fat dairy, and low-carb vegetables, which helps to up your fat intakes to help maintain satiety without overdoing it on the carbs. You should aim for 70 to 80 percent of your daily calories to come from fat, 20 to 25 percent to come from protein, and 5 to 10 percent from carbs in order to maintain ketosis.

“A diet high in unhealthy fats increases the risk of heart disease,” Dr. Calder says, explaining that if someone does choose to pursue the keto diet, they should opt to eat lean protein, low-fat dairy products, and healthy fats, including nuts, nut butters, seeds, avocado, and healthy oils.

Planning ahead can be the key for success on the keto diet to avoid falling into the trap of eating carbs out of convenience. While there are certainly plenty of options when eating out at restaurants, keeping it keto without a plan can be a recipe for disaster.

“I caution anyone who is new to concepts including portion control, meal prepping, grocery shopping, exercise, and, including, but not limited to, even cooking their own meals, as this diet will likely be detrimental to their long-term health,” Mancella said.

Is keto for you?

When it comes to weight loss, Dr. Calder explains that all diets have the same end goal: creating a calorie deficit.

“If your goal is weight loss, you do not need to be on a keto diet to achieve this,” said Dr. Calder. “You can create this deficit by making different changes to your diet and eating patterns, and with physical activity.” She suggests that the average person consider a balanced, heart-healthy diet consisting of lean protein, fruits, vegetables, healthy fats, and high-fiber, whole-grain carbohydrates.

There is no one-size-fits-all approach to dieting and healthy eating. Every body is different, and different people need to find the right dietary plan that fits their physical, emotional, and financial needs.

While the ultra-low-carb nature of keto might be able to help people shed some weight quickly, it is not a universal solution for everyone, and any new diet should be undertaken with guidance from a health care provider.

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Is the Keto Diet Good or Bad? Is Ketosis a Good Way to Lose Weight?

With Michael J. Gonzalez-Campoy, MD, PhD, Zarabi, RD, and Amy M. Goss, PhD, RD

Given all the buzz, adopting a ketogenic diet may be the perfect weight loss plan, especially if you have diabetes, or want to try this approach to lose those troublesome extra pounds. After all, it’s a very low-carb meal plan that promises effective weight loss while also lowering your blood sugar to the point where you could possibly stop taking medication. By all accounts, the “keto” diet, as it’s widely known, may even reverse type 2 diabetes, at least for some lucky individuals.

Another advantage to the keto diet: It can help reduce systemic inflammation, which can have a variety of negative effects on your entire body.

You can create meals that are appealing and delicious when following a keto diet. Photo: 123rf

Unlike some of the other popular low-carb diets, which typically are high in animal protein, the keto diet focuses on getting to the body to burn stored body fat instead of sugar as the main fuel. When body fat is broken down in the liver instead of glucose, s an energy byproduct known as ketones are produced.

Make Certain Your Keto Diet is Well Formulated

While like any diet, you need to find the right proportion and balance of macronutrients (ie, fat, protein, carbs) in order for your body to begin burning accumulated fat rather than stored glucose.

The amount of fat you eat when following a keto diet is quite a bit higher than on most other diets. You’ll want to aim to consume about 60 to 75% of your calories come from dietary fat and 15 to 30% protein, with the remaining calories for carbs, says Sharon Zarabi, RD, director of the bariatric program at Lenox Hill Hospital in New York City.

“There is still some debate on the effects of saturated fats and what constitutes a healthy dose. There has been quite a bit of buzz around grass-fed cows producing cream, dairy, and butter. Ghee has been popular on the market as well, as a clarified form of butter,” Ms. Zarabi says. “It’s really the trans fats that I think people need to understand and the harmful effects on the heart and cholesterol.”

It’s really the trans fats that you’ll want to avoid completely. “Trans fats are highly processed, and heated to a point where they create free radicals in the body, which increase your risk of cancer.,” she says, “Trans fats are found in hydrogenated oils (be on the lookout for this form of fat listed on the ingredients), and these are mostly used in the preparation of processed crackers and packaged foods.”

The best low-carb foods include peppers, cauliflower, greens (eg, spinach, arugula, kale), and zucchini. When starting a keto diet, your goal should be to gradually reduce your carb intake to about 20 grams for at least two weeks but aim for six weeks in order to allow your body to adjust to this fat-burning process.


Once you’ve reached ketosis, you will gain the benefits and be able to take a keto holiday (more on this later), which is necessary to manage for as long as you need to.

Working with a dietitian may be the easiest and more efficient way to find the right dietary balance for your physiological needs and overall health.

“The purpose of the keto diet is to push your body into a state of ketosis, where the body uses fat stores instead of its preferred form of energy, which is glucose,” says Amy M. Goss, PhD, RD, an assistant professor of nutrition sciences in the School of Health Professions at the University of Alabama at Birmingham.

The Pros and Cons of Following a Keto Diet

Is it Healthy to Push Your Body into Ketosis?
“The major benefit of the keto diet is that it does work so you lose weight,” says Ms. Zarabi. “But then again, it is a diet and like all diets, it is a short term solution, something you do, then you stop. It is not really a sustainable diet in real life situations. More importantly, your goal is not just to lose weight—anyone can lose weight. The more necessary goal is to keep the lost weight off.”

The keto diet can be an effective way to reduce excess body fat but there are several cons that should be noted by anyone wanting to follow this eating plan, says Ms. Zarabi says. In fact, the keto diet has serious risks. For one thing, it’s high in saturated fat, which has been linked to heart disease. Additionally, a nutrient deficiency and constipation could occur since the keto diet is very low in fibrous foods such as fruits, vegetables, and whole grains.

Liver problems for those with existing liver conditions could possibly worsen since the keto diet puts stress on the liver, and kidney problems could also occur. 4

If you are considering going on the keto diet, work with a knowledgeable practitioner or seek out a registered dietitian with experience in prescribing it and following you to avoid any adverse effects, Dr. Goss says.

Fair Warning: There Are Challenges to Choosing a Keto Diet

  • The first few days are extremely difficult as your body tries to acclimate to such a low level of carbs. During this adjustment to burning fat instead of glucose, the side effects will make you feel awful; hence the term, keto flu.
  • You’ll be depriving yourself in social situations
  • You’ll need to prepare meals ahead and take them with you since you are confined to eating specific foods.

3 Common Mistakes to Keep In Mind When On a Keto Diet

  • Use Fat Wisely Rather Than Excessively. While the keto diet means your food choices are geared to a low carb/high fat intake, it does not mean adding fat to everything you eat. You do not need to fall for one of the most trendy keto tricks— adding a pat of butter to your coffee. This might be useful at the very beginning as you transition away from a high carb diet but should not be continued once you are past the initial shift once your body has adapted to this new eating rhythm. Instead, listen to your body for cues. If you are feeling hungry right after a meal, you probably didn’t have enough protein or fat. When followed correctly, a keto-based meal will leave you feeling full and satiated for hours.
  • Seek Nutritional Ketosis, Not Higher Ketone Levels. To gain the most benefit from this diet, you’ll want to aim for a level of ketosis between 1.5-3.0 mol/L on a blood ketone meter. You’ll be there when you are eating well-designed meals that carry you through to the next meal without hunger or other adverse symptoms (ie, nausea, insomnia, crankiness, inability to exercise). Higher ketone levels suggest you have more circulating ketones in your blood but don’t confuse this with efficient fat burning, which is the goal of this diet.
  • Ketosis Isn’t Forever. It’s recommended that you follow this diet to arrive at a state in which your body adapts to burning fat and glucose stores for fuel. Then you’ll want to take an occasional ketosis holiday, adding a serving of unprocessed, whole grains to allow your body to chance to work less hard. Staying in ketosis long-term—without breaks— can cause muscle aches, nausea, and fatigue.

Adhering to the keto diet puts your body into a state of ketosis, which sounds similar to ketoacidosis. However, don’t confuse these terms as ketosis and ketoacidosis are two very different physiological states, Dr. Goss explains.

Know the Difference Between Ketosis and Ketoacidosis

“Ketosis is a normal physiological response that occurs when you eat a high fat, low carb diet, while ketoacidosis is more pathological,” she says. “It happens in people with diabetes whose blood glucose is very high (hyperglycemia). You can’t put yourself into ketoacidosis the way you can put yourself into ketosis.”

When in ketosis, the body begins to burn stored fats for energy, and this results in the build-up of acids, known as ketones, in your blood. A person following the keto diet aims to burn unwanted fat by actually pushing the body to rely on fat, not carbohydrates, for energy. This process occurs when there isn’t enough glucose available to burn, so the body turns to stored fats instead.

You are likely to realize that your body has achieved ketosis because you may have a dry mouth, increased thirst, and find yourself needing to urinate more frequently, Dr. Goss says. “You are ridding your body not only of ketones but electrolytes such as sodium, potassium, and magnesium,” which may lead to dehydration, she says, so drinking plenty of fluids will help reduce any problems even if it means more trips the bathroom. “Bad breath is also commonly noticed as a result of the body trying to eliminate acetones produced during ketosis.”

Ketoacidosis most commonly arises with people with diabetes. Diabetic ketoacidosis occurs in response to a severe lack of proper insulin activity whereas alcoholic ketoacidosis is a harmful metabolic condition arising when someone consumes alcohol but no food, explains Michael J. Gonzalez-Campoy, MD, PhD, medical director and CEO of the Minnesota Center for Obesity, Metabolism, and Endocrinology, in Eagan, Minnesota. Either way, this is a dangerous situation.

“Both alcoholic ketoacidosis and diabetic ketoacidosis create medical emergencies due to the rapid change in the body’s acid-base balance,” Dr. Gonzalez-Campoy says. “The rapid drop in the pH of the blood, which is called acidosis, can depress the nervous system and muscle function, causing a person to become unconsciousness due to vascular collapse.”

Common complications of diabetic ketoacidosis include very low blood sugar, or hypoglycemia, and swelling of the brain (cerebral edema). As such, when a person is in ketoacidosis, there is such a high level of ketones produced that can push a person into cardiac arrest (heart attack) or kidney failure. Hence, the very important reason for taking occasional keto breaks go give your body a bit more nourishing carbs.

The Story Behind How the Ketogenic Diet Came to Be

The ketogenic diet was originally formulated by doctors to help treat people with epilepsy, and it was found especially effective in children who didn’t respond to medication.1,2 Indeed, the keto diet has been found to reduce the frequency and intensity of seizures, which are common complications of this condition.

This high fat/low carb diet may also help improve certain other neurological disorders like Alzheimer’s disease and Parkinson’s disease,3 according to the Epilepsy Foundation. More than half the children with epilepsy who were put on the diet experienced half as many seizures, while 10 to 15 percent of the patients who followed this diet became seizure-free.

The keto diet has also been studied as a possible cancer therapy. In a study focusing on people with cancer who followed the ketogenic diet as a medical therapy,4 the authors reported: “There is a great need for complementary approaches that have limited patient toxicity while selectively enhancing therapy responses in cancer versus normal tissues.

Ketogenic diets could represent a potential dietary manipulation that could be rapidly implemented for the purpose of exploiting inherent oxidative metabolic differences between cancer cells and normal cells to improve standard therapeutic outcomes by selectively enhancing metabolic oxidative stress in cancer cells.”

In another study looking at ketogenic diets as a treatment for cancer,5 this research team concluded, “based on the results of rigorous preclinical and clinical studies performed thus far, the KD would appear to be a promising and powerful option for adjuvant therapy for a range of cancers. Cancer-specific recommendations await the findings of randomized controlled clinical trials.”

Proponents of the keto diet say that when and followed precisely, it does not “starve” the body. “A well-formulated keto diet includes all the food groups and therefore provides adequate intake of micronutrients,” says Dr. Goss. “There is ample scientific evidence from randomized clinical trials supporting the therapeutic effects of the diet in treating a number of chronic disease conditions besides epilepsy, including type 2 diabetes , non-alcoholic fatty liver disease, even obesity.”

She adds that the research supports the safety and effectiveness of following a keto diet even in older adults with obesity as it seems to help improve body composition and improve metabolic health.6 “We saw significant reduction in body fat while lean mass was preserved and significant improvements in insulin sensitivity and the lipid profile in response to a ketogenic diet when compared to a standard ‘balanced’ diet,” Dr. Goss explains.

Anyone who takes medications for diabetes or hypertension should consult with a physician before starting on the keto diet, she adds. And it is not for everyone: Individuals who are dependent on insulin (those with type 1 diabetes) should never follow the keto diet, says Dr. Goss.

Additionally, since ketosis can be harmful to a fetus, the keto diet should be avoided during pregnancy. “Also, ketones are harmful to patients who cannot correct the metabolic acidosis caused by them, ie, those with liver, kidney, or pulmonary disease,” Dr. Gonzalez-Campos adds.

The keto diet is not for children or adolescents either, and a long-term complication can be growth retardation in children.5

If you decide to follow the diet, you’ll want to have an individualized meal plan, stresses Dr. Gonzalez-Campos. “The best possible clinical outcome is for each individual to meet her nutritional needs from well-balanced meals,” he says. “Ideally, we should all have the benefit of medical nutrition therapy and we should all avoid extremes in nutrient restrictions.”

Last updated on 02/26/2019 Continue Reading Mediterranean Diet: Anti Inflammatory Foods Behind Health Benefits

Everyone knows someone who’s trying the keto diet, whether it’s Halle Berry or your Uncle Joe. The popular eating plan advises breaking down your daily calories into about 70% fats, 20% protein, and 10% carbs in order to enter a metabolic state called ketosis, where your body burns fat for energy instead of its preferred fuel, carbohydrates.

The diet can prove hard to follow based on sheer restrictiveness alone, but it may also impact your health in other ways besides weight loss. Here’s what you need to know about keto before you ditch healthy whole grains and fruits in the name of New Year’s resolutions.

Short-Term Effects

You’ll likely notice a few key differences during your first days and weeks on the keto diet:

Keto breath

While it’s not necessarily dangerous, bad breath is a known side effect of entering ketosis. When you’re taking in a lot of fat, your liver metabolizes it and eventually converts it into smaller ketone bodies. These ketones (including acetone — yep, like nail polish remover acetone) will circulate in your body and diffuse into your lungs. Your body wants balance, so you’ll exhale ketones to avoid build-up in your bloodstream. Those compounds are what cause keto breath: a metallic-tasting, somewhat stinky side effect.

Keto flu

Valeriia Sviridova / EyeEmGetty Images

During your first week of keto, you may experience flu-like symptoms such as aches, cramping, fatigue, diarrhea, constipation, general weakness, and a skin rash. This is actually a side effect of water and electrolyte loss, and is likely indicative of dehydration.

When you turn to fat for fuel, you lose more water and electrolytes in your urine due to a decrease in your body’s insulin levels and a loss of muscle glycogen. (When you’re in ketosis, you’ll use muscle glycogen for energy first.)


Low-carb diets can have a diuretic effect within the first few days in general, but on keto you’re drastically cutting down on foods with the most water and potassium: produce. Anyone who is planning on doing keto long-term will need to drink additional fluids with electrolytes since you’re taking in less overall but expelling more of them.


The lethargy you experience? Research attributes it to your brain not receiving enough glucose. This side effect appears to be brief, but still uncomfortable and unpleasant.

There’s many suggested interventions for these short-term keto side effects on the internet, but know that there are potential pitfalls of these dietary supplements. While there are benefits for some specific cases, many of us will experience nausea, vomiting, diarrhea, and constipation as a result. Plus, unless they’re prescribed to you by a physician, dietary supplements come with their own safety gamble.

Long-Term Effects

Here’s what you might experiences after a few months (or years) on the keto diet:

GI problems

Beyond the short-term effects of the keto flu, the diet can also negatively impact your digestion and gut in the long run. One 10-year study conducted on using keto to manage pediatric epilepsy found the following GI side effects over time: constipation, high triglyceride levels, high cholesterol, diarrhea, lethargy, iron deficiency, vomiting, and kidney stones.

The processed foods with sugar alcohols allowed on the keto diet also have their own gas, bloating, nausea, diarrhea, and constipation-inducing effects that increase with the amount you eat every day.

Weakened immune system

amphotoraGetty Images

A number of studies suggest keto can disrupt the balance of good and bad bacteria in your GI tract (a condition called dysbiosis) due to high saturated fat intake and eating less fiber. Diets lacking in prebiotic fiber decrease probiotic, “friendly” bacteria as a result. Since the GI tract is considered the “bodyguard” of your immune system, this may impact your gut-brain connection, immune function, and chronic disease risk.

Vitamin and mineral deficiencies

The research on ketogenic diets also suggests you’ll need to take a multivitamin to get enough minerals, calcium and vitamin D — most of which are readily available in plant-based foods. One keto-specific example: Not getting enough selenium, an immune-boosting antioxidant found in plant foods, can cause cardiomyopathy, a hardening of the heart muscle leading to heart failure.

Stas_VGetty Images

An even bigger concern from my POV: Dietary supplements aren’t overseen by the FDA, meaning they’re not evaluated for safety and efficacy in the same way that food and medications are — so you may not be getting exactly what you pay for. And if you are? Well, consuming certain nutrients in supplement form versus food form can induce oxidative stress rather than treating it — and cause more harm than good to your organs.

Increased risk of chronic disease

In order to stay in ketosis, you have to limit carbs, but also to some extent protein. This is the predominant difference between keto and traditional lower-carb diets like Atkins. By relying on dietary fat for most of your calories per day, you limit fiber-rich sources (like fruit, veggies, and legumes) and sources of lean protein (like fatty fish) — some of the most nutrient-dense foods on the planet.

Across the globe, diets high in vegetables and fruit are linked to reducing long-term chronic disease risk, including diabetes, heart disease, and lifestyle-related cancers. Data suggests that the more produce we eat, the better off we are. On keto, however, you have to restrict how many net carbs (and therefore, veggies) you’re consuming per day, minimizing their beneficial effects.

Chronic inflammation

The high-fat intake required for ketosis may change the structure of LDL (“bad”) cholesterol and lipoproteins, which could induce inflammation over time. Chronic inflammation is a biological state in which your body’s cells work overtime to get their regular job done. Healthcare professionals can ID inflammation through blood work by looking for signs of oxidative stress (a.k.a. the damage done by free radicals to organ tissues).

This makes keto tough to recommend, since chronic inflammation is linked to heart disease, and 49% of us are already at risk for it.

Weight cycling

If you can’t maintain any eating plan forever due to its level of restriction and burden, it can lead to weight cycling — the process by which you gain a lot of weight and lose a lot of weight when “dieting” versus when you’re off of a diet. That can lead to increased chronic disease risk, not to mention how it can make weight loss more difficult the more often you do it.

The ketogenic state in particular can increase the hormones that make you feel full and decrease the hormones that make you feel hungry. Sounds great, right? Well, once you’re off the keto diet, the appetite-suppressing hormones will increase significantly from your baseline. Meaning that you’ll likely feel even hungrier than you did before you started!

The Bottom Line

Any plan that restricts real, whole foods, and requires taking supplements comes at a cost, including financial and environmental ones.


Cutting back on these nutritious foods for weight loss propagates diet myths about what it looks like to eat in a balanced way. That said, weight loss is highly personal and unique to every single one of us. Ultimately, if you can find better health (physical and psychological) on keto, then of course I’d encourage you to stick with it!

But since the data shows me quite the opposite (and since we can’t always rely on “willpower” to keep us in check): Approach weight loss first by considering your lifestyle and shifting toward healthier eating habits through behavior changes that promote physical, mental, and psychological well-being for life.

Always consult with your doctor before starting any weight-loss plan, but if you’re currently taking meds for diabetes management, it is absolutely essential that you talk to your endocrinologist before beginning keto. Some medications actually require eating some carbohydrates to ensure your safety.

For better ways to do lose weight and get healthier without uprooting your entire life, check out our Nutrition Director’s new book, Dressing on the Side (and Other Diet Myths Debunked): 11 Science-Based Ways to Eat More, Stress Less, and Feel Great About Your Body.

Jaclyn London, MS, RD, CDN, Good Housekeeping Institute Director, Nutrition Lab A registered dietitian with a Bachelor of Arts degree from Northwestern University and a Master of Science degree in Clinical Nutrition from New York University, Jaclyn “Jackie” London handles all of Good Housekeeping’s nutrition-related content, testing, and evaluation.

The complete guide to ketosis

Does the brain need carbs?

There’s a long-standing yet misguided belief that carbs are necessary for proper brain function. In fact, if you ask some dietitians how many carbs you should eat, they’ll likely respond that you need a minimum of 130 grams per day to ensure that your brain has a steady supply of glucose.

However, this isn’t the case. In fact, your brain will remain healthy and functional even if you don’t eat any carbs at all.

Although it’s true that your brain has high energy demands and requires some glucose, when you’re in ketosis, there are plenty of ketones to supply a good portion of its fuel.5 Fortunately, your liver will always make the small amount of glucose your brain needs, even under conditions of complete starvation.6 This process, known as gluconeogenesis (literally “making new glucose”), can also provide glucose for other structures that need it, such as the red blood cells and a portion of the kidneys.

This system allowed our hunter-gatherer ancestors to go for long periods without eating because they had access to a fuel source at all times: stored body fat.

In truth, being in ketosis doesn’t have any adverse effects on brain function. On the contrary, many people have reported that that they feel sharper mentally when they’re in ketosis.7

Food for thought: Does the brain need carbs?

2. Benefits of ketosis

In addition to providing a sustainable energy source, ketones – and in particular BHB – may help reduce inflammation and oxidative stress, which are believed to play a role in the development of many chronic diseases.8

Indeed, there are several established benefits and potential benefits of being in nutritional ketosis.

Established benefits:

  • Appetite regulation: One of the first things people often notice when they’re in ketosis is that they’re no longer hungry all the time. In fact, research has shown that being in ketosis suppresses appetite.9 One study looked at people who lost weight by following a ketogenic diet for eight weeks and then reintroduced small amounts of carbs. The researchers reported that levels of ghrelin (the “hunger hormone”) were suppressed in those who remained in ketosis, whereas those who were no longer in ketosis had higher ghrelin levels.10
  • Weight loss: Many people automatically eat less when they restrict carbs and are allowed as much fat and protein as they need to feel full. Because ketogenic diets suppress appetite, decrease insulin levels, and increase fat burning, it isn’t surprising that they’ve been shown to outperform other diets intended for weight loss.11
  • Reversal of diabetes and prediabetes:12 In people with type 2 diabetes or prediabetes, being in ketosis can help normalize blood sugar and insulin response, potentially leading to the discontinuation of diabetes medication.13
  • Potentially enhanced athletic performance: Ketosis may provide an extremely long-lasting fuel supply during sustained exercise in both high-level and recreational athletes.14
  • Seizure management: Maintaining ketosis with the classical ketogenic diet or less stringent modified Atkins diet (MAD) has been proven effective for controlling epilepsy in both children and adults who don’t respond to anti-seizure medication.15

There is also exciting early research suggesting that ketosis may be beneficial for many other conditions, such as reducing the frequency and severity of migraine headaches, reversing PCOS, perhaps enhancing conventional brain cancer therapies, possibly slowing down the progression of Alzheimer’s disease, along with potentially helping people live longer, healthier lives. Although higher quality research is needed to confirm these effects, much of the early research is very encouraging.

3. Nutritional ketosis vs. ketoacidosis

Nutritional ketosis and diabetic ketoacidosis are entirely different conditions. While nutritional ketosis is safe and beneficial for health, ketoacidosis is a medical emergency.16

Unfortunately, many healthcare professionals don’t really understand the distinction between the two.

Ketoacidosis occurs mainly in people with type 1 diabetes if they do not take insulin. In diabetic ketoacidosis (DKA), blood sugar and ketones rise to dangerous levels, which disrupts the blood’s delicate acid-base balance. People in ketoacidosis feel extremely ill and experience profound dehydration, vomiting, abdominal pain, and weakness. DKA requires hospitalization so that IV fluids and insulin can be given to gradually and safely lower blood sugar.17

In nutritional ketosis, BHB levels typically remain below 5 mmol/L. However, people in diabetic ketoacidosis often have BHB levels of 10 mmol/L or above, which is directly related to their inability to produce insulin. This graph shows the vast difference in the amount of ketones in the blood between ketosis and ketoacidosis:

When blood ketone levels rise beyond a certain level, a pancreas capable of making insulin will release enough to shut down further ketone production.18 By contrast, the pancreas of a person with type 1 diabetes cannot make insulin. So unless insulin is given via injection or IV, ketones will continue rising to life-threatening levels.

Other people who can potentially go into ketoacidosis are those with type 2 diabetes who take medications known as SGLT2 inhibitors, such as Invokana, Farxiga, or Jardiance.19

Also, in rare cases, women who don’t have diabetes can develop ketoacidosis while breastfeeding.20

However, for most people capable of producing insulin, it’s nearly impossible to go into ketoacidosis.

4. Tips for getting into ketosis

There are a number of ways you can get into nutritional ketosis safely and effectively.

  • Reduce daily net carb intake to less than 20 grams: Although it’s possible that you may not need to be this strict, eating fewer than 20 grams of net carbs every day virtually guarantees that you’ll achieve nutritional ketosis. What does 20 grams of carb look like? Use our visual guide to find out, or simply try our keto recipes and meal plans that limit carbs to less than 20 grams per day.
  • Try intermittent fasting: Going for 16-18 hours without eating may help you get into ketosis more quickly.21 This is easy to do by simply skipping breakfast or dinner, which may feel very natural on an appetite-suppressing keto diet.
  • Don’t fear fat: Eating plenty of fat is a necessary and delicious part of ketogenic eating! 22 Make sure to include a source of healthy fat at each meal.
  • Cook with coconut oil: In addition to being a natural fat that remains stable at high heat, coconut oil contains medium-chain fatty acids that can boost ketone production and may also have other benefits.23
  • Exercise, if possible: During the transition into ketosis, you may not have enough energy to engage in vigorous physical activity. However, simply going for a brisk walk may help you get into ketosis more easily.24

Even more tips for how to get into ketosis on a keto diet

Supplements not required

Note what’s not on the list above: you do not need expensive supplements, like exogenous ketones or MCT oil (medium-chain triglycerides). These supplements will likely not help you lose weight or reverse disease. At least there’s no evidence for that.25

Ketone supplements do not lower insulin or blood sugar, and don’t increase fat burning.26 It’s hard to believe that they would have any direct benefits for weight loss or type 2 diabetes reversal.27

People claiming huge benefits of these supplements – despite the lack of solid scientific support – may sometimes have a financial reason to believe in the supplements. Some of these products are sold under a multi-level marketing arrangement, where sales people are paid based on commission. For example, the company Prüvit sells drinkable ketones, called KETO//OS, with a multi-level marketing structure.

The salesperson might tell you that their product is fantastic and has changed his or her life and makes you lose weight, etc. But these benefits are basically unproven. Take all such stories with a grain of salt.

What these ketone supplements might do is possibly improve mental and physical performance for a short time. To the best of our knowledge, this potential and often mentioned benefit is also unproven. They do raise blood levels of ketones, an effect that can last anywhere from one to a few hours.

We’re not saying don’t buy these supplements. Perhaps you want to try them for yourself, and see how they make you feel. But you don’t need them to be successful on a keto diet or to get into ketosis. Here’s our big test of keto supplements:

Exogenous ketone supplements: Do they work?

5. Protein’s effect on ketosis

Although getting sufficient protein on any diet is important for preventing muscle loss, many questions have been raised about protein’s impact on ketone levels.

During digestion, protein is broken down into individual amino acids, which trigger the release of insulin. Although the amount of insulin needed to transport these amino acids into muscles is small, when large amounts of protein are consumed, the rise in insulin might potentially reduce ketone production to some extent.

For this reason, ketogenic diets for epilepsy are restricted in protein as well as carbs, which ensures that ketone levels remain elevated at all times.

However, protein’s effect on ketosis seems to be highly individual.

Some people do report that their ketone levels are significantly lower when they eat more than a modest amount of protein.28

By contrast, others may be able to eat quite a bit of protein without experiencing any changes in ketosis. For example, when Diet Doctor’s Bjarte Bakke conducted several n=1 experiments to see how much protein he could eat and still remain in ketosis, he found that keeping net carb intake below 20 grams per day was what ultimately mattered regardless of his protein intake.

Thus far, the scientific literature does not support the concern that too much protein worsens blood sugar control for most individuals. For instance, two studies showed a diet with 30% of calories from protein improved glycemic control.29 And another study found patients with type 2 diabetes eating a 50g protein meal had no significant increase in serum glucose concentration.30

If you want to stay in ketosis and still eat plenty of protein and are concerned about potential negative effects, it might be a good idea to conduct your own n=1 experiments in order to determine your personal protein threshold. It may be higher than you think.

Read more about protein on a ketogenic diet

6. What is optimal ketosis?

Getting into ketosis on a ketogenic diet is not a black or white thing. It’s not like you’re either in ketosis or out of ketosis. Instead, you can achieve different degrees of ketosis. The definition of “optimal” ketosis my vary depending on your goals. For instance, treating seizures may require a higher ketone level, where as losing weight or improving blood sugar may depend less on the degree of elevation. This chart demonstrates this visually.31 The numbers below refer to values when testing blood ketone levels.

  • Below 0.5 mmol/l is not considered “ketosis,” although a value of, say, 0.2 demonstrates that you’re getting close. At this level, you may not be at your maximum fat-burning zone.
  • Between 0.5 – 3 mmol/l is nutritional ketosis. You’ll likely be getting a good effect on your weight and metabolic improvements.32
  • Around 1.5 – 3 mmol/l is called “optimal” ketosis by some. However, the concept of optimal ketosis is controversial, and it’s unclear if it offers any substantial benefits over the 0.5-1.5 level. Exceptions could be treating seizures or those interested in maximum mental and physical performance gains.33
  • Over 3 mmol/l is higher than necessary. It will probably achieve neither better nor worse results than being at the 1.5–3 level.34 Higher numbers can also sometimes mean that you’re not getting enough food (“starvation ketosis”).35 In people with type 1 diabetes, ketone levels over 3.0 mmol/L can be caused by a severe lack of insulin that requires urgent medical attention.36
  • Over 8–10 mmol/l: It’s normally impossible to get to this level just by eating a keto diet. It means that something is wrong. The most common cause by far is type 1 diabetes, with a severe lack of insulin. Symptoms include feeling very sick with nausea, vomiting, abdominal pain and confusion. The possible end result, ketoacidosis, may be fatal and requires immediate medical care.

Stories about achieving long-term ketosis

Here are the three reports from a 2-month experiment in reaching optimal ketosis:

  1. Experiment: Optimal ketosis for weight loss and increased performance
  2. Four weeks of a strict keto diet and ketone monitoring
  3. Final report: Two months of a strict keto diet and ketone monitoring

Do I have to reach optimal ketosis to experience the benefits?

In short, no. Many of the benefits, such as weight loss, are experienced at lower levels of ketosis (above 0.5 mmol/L).

However, you might need to reach higher levels of ketosis for high-level physical performance. There’s also a time element involved, it takes weeks or even a few months for the body to adapt completely. For more on this, here’s an interesting article from two of the top keto researchers in the world, Drs. Stephen Phinney and Jeff Volek:

Virta Health: Keto-adaptation – some clues to its complexity

7. Signs that you are in ketosis

There are several signs that suggest you’re in ketosis, although measuring your ketones is the only objective way to verify it. Here are the most common ones:

  • Dry mouth or a metallic taste in the mouth.
  • Increased thirst and more frequent urination.
  • “Keto breath” or “fruity breath,” which may be more apparent to others than yourself. Learn more
  • Initial fatigue, followed by an increase in energy.
  • Decrease in appetite and food intake (one of the more welcome side effects!).

Measuring ketones

There are three ways to measure ketones, which all come with pros and cons. For a detailed comparison, see our full guide to the best way to test ketones.

For a shorter version, keep reading below. Note that we have no affiliations with any of the brands mentioned here.37

  1. Urine strips
  2. Breath ketone analyzers
  3. Blood ketone meter

1. Urine strips

Urine strips are the simplest and cheapest way to measure ketosis. It is the first option for most beginners on a keto diet.

Dip the strip in your urine, and 15 seconds later the color change will show you the presence of ketones.38 If you get a high reading (a dark purple color), you’ll know that you’re in ketosis.

Pro: Ketone strips are available in regular pharmacies or via Amazon, and they’re very cheap. A strongly positive test reliably proves that you’re in ketosis.

Con: Results can vary depending on how much fluid you drink. By drinking more water, you dilute the concentration of ketones in the urine and thus a lower level of ketones will be detected on the strips. The strips don’t show a precise ketone level. Finally, and most importantly, as you become increasingly keto-adapted and your body reabsorbs ketones from the urine, urine strips may become unreliable, even if you’re in ketosis.

This happens when the body becomes more adapted to using ketones, meaning that they increasingly stay in the blood to be used as energy instead of being lost through the urine. In one study, after 3 weeks the kidneys were found to excrete ketones at one third the rate, despite having the same blood ketone levels:

Diabetes 1985: Ketone body production and disposal in diabetic ketosis: a comparison with fasting ketosis

Thus, the test may sometimes stop working – always showing a negative result – when you’ve been in ketosis for several weeks.

Order urine strips at Amazon

2. Breath-ketone analyzers

Breath-ketone analyzers are a simple way to measure ketones.39 At $169 and up they are more expensive than urine strips. But they are cheaper than blood-ketone meters in the long run, as they are reusable any number of times.

These analyzers do not give you a precise ketone level when used on their own, but provide a color code for the general level.40

You can also hook the device up to a computer or mobile phone (newer models) to get a more exact ketone number via the app. According to the manufacturer the device gives a decent correlation with blood ketones in most but not all situations.

Pro: Reusable, simple test.

Con: Does not always correlate well with blood ketones. Not always accurate, and can in some situations show entirely misleading values. For example, if you recently ate a lot of carbs, this can result in misleading high values on the Ketonix. More expensive than urine strips, and higher cost upfront than a blood meter.

Order Ketonix

Video: Using breath-ketone analyzers

3. Blood-ketone meters

Blood-ketone meters show an exact and current level of ketones in your blood.41 They are the gold standard and the most exact way to measure your ketosis level on a ketogenic diet. They used to be quite expensive, but now it’s possible to get cheaper test strips.42

A new startup called Keto-Mojo is offering blood ketone testing for about $1 per test. In our big test of blood-ketone meters we find that it may be the best option if price is a concern.

Pro: Exact, reliable.

Con: Still expensive (at least $1 per test). Requires pricking your finger for a drop of blood.

Which is the best ketone meter on the market? The big test

Order the Keto-Mojo meter

Order the blood-ketone meter Precision Xtra with everything included, at Amazon

What if you’re not in ketosis?

If you’re on a keto diet but aren’t seeing experiencing any signs or symptoms being in ketosis, here are a few strategies that may help:

  • Track your carb intake. While we don’t recommend counting or tracking calories, it can be helpful to log your carb intake to make sure you’re truly eating less than 20 grams of carb. Use an online site or app, such as Cronometer.
  • Test blood ketones in the late morning or afternoon. Blood and urine ketones vary throughout the day, as well as from person to person.43 Many people find that their blood ketone levels are usually lowest right after waking up.44 Try testing later on, preferably a few hours after eating. Even if you’re only in ketosis for a portion of the day, you’re still getting some benefits, as discussed in this talk by Dr. Steve Phinney: Achieving and maintaining nutritional ketosis.
  • Try to be patient. Although some people get into ketosis relatively quickly, it may take others a while.45 Unfortunately, people who are insulin resistant often seem to have a longer journey.46 Put in a solid month of consistent keto eating, and try to ramp up your physical activity, if possible. Within four weeks, you should definitely be in ketosis and experiencing its benefits.

Which is the best ketone meter on the market?

GuideWith a blood ketone meter, you can test for blood levels of ketones. Here’s our review of the top options.

8. Side effects, fears and potential dangers

Side effects typically happen within the first few days of starting a ketogenic diet and include headache, fatigue, lightheadedness, irritability, cramps, and constipation. These are known collectively as the “keto flu,” which can be remedied by managing fluids and electrolytes, among other things. Read more about the keto flu.

Is being in ketosis safe for everyone?

Being in ketosis is safe for most people, and it can provide many health benefits, including weight loss, optimal blood sugar and insulin levels, to name a few.

However, certain individuals should only follow a ketogenic diet under medical supervision, and others are best off avoiding it altogether.

Conditions that require medical supervision and monitoring during ketosis:47

  • Type 1 diabetes
  • Type 2 diabetes on insulin or oral diabetes medications
  • High blood pressure on medication
  • Liver, heart, or kidney disease
  • History of gastric bypass surgery
  • Pregnancy

Conditions for which ketosis should be avoided:

  • Breastfeeding women
  • Individuals with rare metabolic conditions that are typically diagnosed in childhood, such as enzyme deficiencies that interfere with the body’s ability to make and use ketones or to properly digest fats.48

The keto flu, other keto side effects, and how to cure them

GuideDuring the first few days of a keto diet, you can experience the keto flu. You can feel tired, have a headache, and be easily annoyed. Learn all about the keto flu and how to avoid it here.

Recommended viewing

The case for nutritional ketosis

Nutritional ketosis: metabolic regulation and signaling

A year of self-tracking in nutritional ketosis

Pros and Cons of the Ketogenic Diet

What You Need to Know About Keto

Though it may seem new to your newsfeed, the ketogenic diet has been around since the 1920s. The low-carbohydrate, high-fat diet gained a foothold when proven to reduce seizures in pediatric patients with epilepsy. While still prescribed for that purpose today, the diet is now touted as a weight loss tool.

Breaking Down the Keto Diet

The keto diet is all about cutting carbs and eating more fat. Here’s what the daily breakdown of carbs, protein and fat looks like:

  • 5 percent of calories from carbohydrates, including low-carb, non-starchy vegetables and small amounts of leafy greens. The keto diet excludes carb-rich foods like grains, beans, fruits and starchy vegetables.
  • 20 percent of calories from protein, such as meat, eggs and cheese.
  • 75 percent of calories from fat, such as oils, unprocessed nuts, butter and avocado.

According to Dietitian Richelle Gomez, MS, RDN, LDN, Northwestern Medicine McHenry Hospital, the ketogenic diet is designed to burn fat by cutting carbs. “Your body turns carbohydrates into glucose for energy,” she explains. “When you cut carbs from your diet, you switch to burning fatty acids, or ketones.”

Breaking down fats for energy is called ketosis. It takes about three weeks of carbohydrate elimination for your body to transition into ketosis.

Here are the pros and cons of the keto diet.


Weight Loss

“There has been anecdotal evidence of people losing weight on the ketogenic diet,” says Melinda R. Ring, MD, director of Northwestern Medicine Osher Center for Integrative Medicine. “People also report feeling less hungry than on other types of restricted diets.”

Gomez says people feel less hungry because fatty foods take a longer time to break down in the body. Weight loss not only comes from ketosis, but also from reducing calorie intake by eliminating food groups.

No More Low-Fat

On paper, burning fats by eating more of them is enticing, which is why the diet has become popular. The keto diet allows many people to eat the types of high-fat foods that they enjoy, such as red meats, fatty fish, nuts, cheese and butter, while still losing weight.

Health Benefits for Specific People

The keto diet helps reduce seizures in pediatric patients with epilepsy. Endurance athletes and body builders also use it to scrap fat in short timeframes. The keto diet is being studied for mitigating symptoms for patients with progressive neurological disorders like Parkinson’s disease, but scientific research has not confirmed benefits for these populations.


Difficult to Sustain

Because of the stringent food restrictions, many find the keto diet hard to stick to.

“The ketogenic diet can be effective for weight loss when used in a short time period followed by the adoption of healthier eating habits,” says Cardiologist Kameswari Maganti, MD,Northwestern Medicine Bluhm Cardiovascular Institute. “Unfortunately, it lends itself to yo-yo dieting, which increases mortality.”

Ketosis is difficult to achieve because it’s like a light switch: either on or off. Individuals who consistently track food intake are more likely to remain in ketosis. But the only way to tell if your body is in ketosis is a blood test.

Calorie Depletion and Nutrient Deficiency

“Because the keto diet is so restricted, you’re not receiving the nutrients — vitamins, minerals, fibers — that you get from fresh fruits, legumes, vegetables and whole grains,” says Dr. Ring.

Due to these deficiencies, people also report feeling foggy and tired. These symptoms have been dubbed “the keto flu.” Constipation is also common on the keto diet due to the lack of fiber.

Bad Fats in Practice

The high-fat nature of the diet could also have negative impacts on heart health. The American Heart Association recommends limiting saturated fat intake to 5 to 6 percent. “In practice, many people eat high amounts of saturated fats, which could increase cardiovascular disease risk,” says Dr. Maganti. “We see an increase in lipids, or fats, in the blood of patients on the keto diet within six to eight weeks.”

Renal Risk

“Patients with kidney disease have an increased risk of requiring dialysis on the keto diet due to the additional ketones that their renal system has to process,” says Dr. Maganti.

Some people also experience dehydration on the keto diet because they’re eradicating glycogen, which holds water, from their bloodstream.

Food Obsession

“When you micromanage your food intake by tracking how much you eat, it disconnects you from what your body is asking for,” says Gomez. “You start using outside numbers to determine what to eat instead of listening to your body.”

Monitoring food so closely can lead to psychological distress, such as shame, and binge eating. Restriction can lead to bingeing, which often leads to guilt, which then leads back to restriction in a continuous cycle.

Other Approaches

Both Dr. Ring and Dr. Maganti recommend balanced approaches, like the Mediterranean diet, for long-term weight loss.

“You can still receive the benefits of ketosis while eating a varied and balanced diet through intermittent fasting,” says Dr. Ring.

Gomez advocates making small changes based on your health goals. “All foods fit into a healthy diet,” she says. “It’s a matter of moderation and finding ways to eat the foods you love without overindulging.”

Consult your physician or a dietitian if you’re looking to change your diet.

What are the Pros and Cons of the Keto Diet?

Few eating trends have captivated popular attention in recent years as much as the Ketogenic Diet. In our previous two articles, we’ve discussed the diet’s historic start as a treatment for epilepsy and disclosed what it takes to follow it correctly.

But is the ketogenic diet worth following? Like all eating strategies, there are some serious pros and cons to weigh before beginning. By the end of this article, you’ll be one step closer to understanding whether going keto is right for you.*

*The information on this site is informative in nature and should never be construed or interpreted as a substitute for medical advice or an endorsement for this diet. No information on this site is intended to be instructional and should not be considered or used as medical diagnosis or treatment. Each person is different, and the way your body responds to a particular diet may be significantly different from the way other people respond. You should speak with your physician or healthcare professional before starting any diet or exercise program.

Quick Keto Overview

As we touched on before, the ketogenic diet is an eating strategy where you power your system on fat, rather than carbohydrates. A standard ketogenic diet consists of 75% fat, 20% protein, and 5% carbohydrates, though there is some room for modification to meet your personal goals. If you eat 2,000 calories per day, this breaks down to about 167 grams of fat, 100 grams of protein, and 25 grams or fewer of carbohydrates.

By minimizing your carbohydrate intake and consuming healthy fats instead, the ketogenic diet puts your body into ketosis. This is a metabolic state where the liver converts fats into acids called ketone bodies that it uses for fuel. This process simulates fasting conditions to switch up your energy supply. Naturally, there are some significant side effects from this process; some positive and others less so.

What will the ketogenic diet do to your body? Below are some of the diet’s most common reported side effects – both positive and negative.


There’s a reason why the ketogenic is so popular today; it has been shown to produce the following changes in health.

Can Help You Lose Weight

Research reveals that the diet significantly impacts the amount of body fat you metabolize for energy, and following a diet based around high-fat foods tends to boost satiety so that you want to snack less during the day. This keeps calorie counts under control, which can lead to weight loss and an overall change in your body composition.

May Improve Cognitive Functioning

The ketogenic diet has long been understood to affect brain functioning. The high fat content in the diet helps reduce inflammation that triggers nerve pain in the brain, and research shows that overweight patients who go on the diet experience fewer migraines than they did previously.

Studies are also speculative that the diet can reduce the symptoms or hinder the development of neurological diseases like Alzheimer’s and Parkinson’s, and children on the diet often exhibit better concentration and fewer ADHD symptoms than their peers. Further evidence shows that powering the brain on ketones can improve the outcome after traumatic brain injuries, though most research today has only looked at rat populations.

May Slow Various Cancers

Evidence shows that following a keto diet might slow the spread of tumor cells and even suppress their growth altogether.

May Reduce Inflammation from High Blood Sugar

The ketogenic diet helps reduce your insulin levels, which prevents it from triggering various health problems. There is also evidence that the diet can reduce your overall insulin sensitivity, which makes it easier for your body to process carbohydrates effectively.

Helps You to Kick the Sugar Habit

Sugar addiction is a serious problem for millions of people but following the ketogenic diet can may make it easier to fight off cravings because each meal leaves you satiated. As the diet restricts your carbohydrate intake to 25 grams per day, you’ll cut your sugar intake down to almost nothing, which makes it easier to quit the habit altogether.

May Increase Female Fertility

Over 10 percent of American women under 44 struggle to conceive or carry a pregnancy to term. Many find that following the ketogenic diet seems to help some of the underlying issues with fertility. The eating strategy positively affects weight and insulin levels, and it can reduce the hormonal effects of polycystic ovarian syndrome (PCOS).


No diet is perfect, and the ketogenic diet has its share of downsides.

Most Initial Weight Loss is Water

It’s not uncommon to experience dramatic weight loss when you first go keto, but for many these losses can’t be sustained and they rarely last. These initial losses are primarily attributed to water weight from burning your glycogen stores. If you add carbs back to your diet, some of those pounds will return.

Long-term Research is Limited

Despite the diet’s popularity today, little is known about the effects of the Ketogenic diet on your health over time. This leaves researchers with more questions than answers about its effectiveness after years or decades of commitment. There isn’t conclusive evidence about whether Ketogenic followers will regain the weight or suffer other health consequences, meaning that following the eating method today might potentially put you at risk in the future.

The Diet May Trigger Brain Fog

Your brain is primed to run on glucose and limiting this supply can affect your mental functioning. This is because your body struggles to transition from using an available energy supply to making its own, which can affect brain functioning in ways that lead to memory loss, headaches, slower cognition, and general ‘brain fog’.

These effects are usually temporary, and they dissipate once the brain adjusts to burning ketone bodies instead. However, those who are predisposed to mental health issues like anxiety and depression might feel these effects more acutely, meaning that the ketogenic diet might not be the best choice for them.

Going Keto Limits Your Fruit and Starchy Vegetable Intake

Entering ketosis requires you to restrict particular fruit and vegetable consumption, which may make it difficult to consume enough vitamins, minerals, and fiber to stay healthy. Many high-carb whole foods are considered very healthy, so following the diet for the long-term could lead to health problems if you aren’t careful to keep your nutrient levels in check.

Easy to Accidentally Eat Unhealthy Fats

The Ketogenic diet prioritizes fats above all other macronutrients, but it can be hard for beginners to know which ones to invest in. Many people who try to go Ketogenic fail to choose quality fats like those that come from plants and organic or grass-fed animal products. Filling up on canola oil or other “cheap” fats can be damaging for your health in the long run.

Potentially Dangerous for Those at Risk of Eating Disorders

The ketogenic diet, as with some other diets, requires scrutiny of each meal you eat, which can pose a problem for those with a history of disordered eating. Following the eating plan can become obsessive for some people and categorizing so many foods as “off limits” can lead to negative associations with food that are physically and mentally damaging. Likewise, failing to follow the diet perfectly might lead to feelings of guilt and inadequacy, all of which should be carefully weighed before beginning.

Might Trigger Kidney Stones

Between three and ten percent of people who follow the ketogenic diet for months at a time to develop kidney stones, partly because of its lack of fiber. You can reduce your risk by ensuring that you stay hydrated and eating those foods that are keto approved with higher fiber content.

Potential for Ketoacidosis

If you put yourself in ketosis for too long, you risk developing excessively high levels of acids in your blood, which leads to a condition called ketoacidosis. This condition can leave you queasy, short of breath and mentally confused. In extreme cases, it might lead to hospitalization.

Might Cause Digestive Distress

When you first transition to keto eating, the high-fat, low-carb diet has the potential to lead to digestive problems like diarrhea or constipation. The symptoms typically disappear after a few weeks, but they can be alarming at first.

Bad Breath is Common

One temporary yet inconvenient side effect of entering ketosis is “fruity” breath. This happens because your body is breaking down acetoacetic acid, which many people say produces a similar smell to nail polish. Your urine while you’re in ketosis often smells the same way.

Ketosis Could Affect Your Athletic Skills

The evidence is mixed about how the ketogenic diet affects athletic performance, and some people find that this eating strategy hurts their results. Athletes that are looking to maximize their power may struggle to put on weight and improve their strength with a low carbohydrate diet, but endurance athletes that need to sustain their energy for long periods of time might become more efficient if they fuel themselves on fat stores. Even so, the diet is more difficult for athletes to follow than less active people because of the difficulty of adequately powering yourself without carbs.

You Might Get the “Keto Flu”

As your body acclimates to the ketogenic diet, you might go through a period of transition that leaves you feeling weak and exhausted. Followers of the eating plan call this the keto flu, and it can leave you feeling weak, lightheaded, irritable, mentally slow, constipated, and lethargic. The symptoms usually subside within a few days to a few weeks.

Dos and Don’ts of the Keto Diet*

If you’re ready to try following the ketogenic diet, then you need to set yourself up for success from day one. Below are some dos and don’ts to keep in mind when you first begin.

*The information on this site is informative in nature and should never be construed or interpreted as a substitute for medical advice or an endorsement for this diet. Each person is different, and the way your body responds to a particular diet may be significantly different from the way other people respond. You should speak with your physician or healthcare professional before starting any diet or exercise program.


  • Stick with healthy fats like eggs, avocado, and extra virgin olive oil
  • Eat low-carb greens as much as possible to maximize your nutrient intake
  • Eat real food made from whole ingredients (nothing processed)
  • Source organic, grass-fed animal products as much as possible
  • Stay hydrated- it helps offset the loss of fiber in your diet
  • Keep a food journal to track how you feel over time
  • Consider a modified keto diet if the restrictions are too severe
  • Consult with your doctor before beginning if you have underlying medical conditions
  • Consider nutritional coaching to ensure you follow the eating plan correctly
  • Replace your electrolytes by drinking bone broth


  • Avoid eating fast food as much as possible (the fat content is low quality, even in keto-friendly meals)
  • Don’t avoid looking at nutritional information before you eat- most foods have more carbs than you would expect
  • Avoid “bad fats” like corn, soybean, canola or hydrogenated oil
  • Avoid any processed food listed as low-fat, as most manufacturers make up for the lack of flavor with extra sugar (carbs)
  • Don’t overeat. The high satiety of keto-friendly food might mean that your place looks emptier at mealtimes than it did before. Avoid overstuffing yourself out of habit.
  • Don’t stress about calories. There’s little reason to monitor your amounts if your macronutrient ratios are where they should be.
  • Avoid consuming too many nuts or dairy products, as they are typically calorie-dense and are easy to overeat.

Up Next: What Does a Keto Meal Plan Look Like

Our next blog post will show you how to create a keto meal plan. We’ll dive into a keto-friendly food guide and offer a 5-day meal plan for those that interested in getting started. Stay tuned!


Fans of the high fat, low-carb keto diet praise its appetite-crushing benefit, which is why keto dieting is so popular for weight loss. But since we don’t live in a keto-friendly world, the call of carb-rich fare — from healthy options, like fruit, yogurt and oatmeal to less healthy foods, like pizza, French fries and dessert — can make it hard to stick with the keto diet. Even if you’re not craving carbs, a normal social activity, like dinner at a friend’s house, can pose problems. Enter keto cycling. In this fairly new approach, you cycle on and off the keto diet at various intervals. Though this may sound like the best of both worlds, there are some red flags you should know about.

Keto cycling, explained

The keto diet is designed to encourage your body to adapt to using fat instead of its preferred fuel source, glucose, which is the substance that’s broken down from the carbohydrates you eat. Though it sounds simple enough, the process involves many biological modifications and it may take a few weeks for these changes to occur. You’ll lose weight during this process — initially mostly water weight — as your body depletes its remaining carbohydrate stores (known as glycogen) and makes this adaptation.

The main challenge keto dieters face is the extreme carb limit, which is capped at about 5 percent to 10 percent of your daily calorie intake, or around 20 grams of carbohydrates per day, depending on your individual calorie level. This amount of carbs is less than the amount in a large banana and given that even non-starchy foods, like nuts and broccoli, contain some carbohydrate, you’ll reach the cap easily. That means doughy foods, like pizza, pasta and bagels, as well as sweets, are strictly off limits. That’s why keto cycling is so appealing.

Though it has no official definition and there’s no actual science to back up its effectiveness, many people take it to mean following the keto diet for five or six days and then following a higher carb menu for a day or two. Besides the obvious benefit of being less rigid, adding back nutritious carbs, like fruit, beans and whole grains, can provide a spectrum of health-protecting substances, including fiber, which is often low on a typical keto menu.

How does keto cycling impact weight loss?

According to the recently released National Lipid Association’s scientific statement published in “The Journal of Clinical Lipidology”, this type of eating pattern is difficult to maintain and while those who follow it often experience an initial weight loss advantage, over time, the keto diet’s weight loss benefits aren’t any better than a more balanced plan.

In theory, keto cycling might make it easier to follow this program, but according to Molly Devine, RD, owner and founder of MSD Nutrition Consulting and Eat Your Keto, the reality may be quite different. “Few people have the ability to go on and off keto successfully,” she says, explaining that the main challenge is intense cravings for carbs and sugar, which come back once you reintroduce these foods. In Devine’s experience, this is true whether you take a break for say, a holiday weekend, or even just a meal.

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“For those who have struggled with sugar addiction and battled getting sugar out of their diet, following a strict ketogenic diet is the first time they don’t feel overwhelmed by cravings due to the metabolic shift from glucose for fuel to ketones. Keto cycling or cheat meals are very challenging for this group because as soon as they get a taste of those foods, the cravings hit hard and they have a tough time getting back on the wagon,” she explains.

Franziska Spritzler, RD, CDE, a writer and expert on the medical review board of agrees, but says it can depend on the person. She explains that some people do well knowing they can have a small scoop of ice cream or another non-keto treat on occasion — and that planning for these non-keto foods can make it easier to stay on the keto diet and facilitate weight loss and better blood glucose control. But she admits that for other people, this approach can lead to intense carb cravings, making it difficult to return to the keto diet.

What are the risks of keto cycling?

Setting aside intense cravings, there may be other risks of cycling on and off the keto diet. In one short-term, small study, researchers investigated the impact of following a strict keto diet for six days and then going off plan by consuming a drink containing 75 grams of carbohydrate. For reference, that’s slightly less than the amount of carbs in two cans of soda. The damage: “We saw a temporary increase in the levels of endothelial microparticles (sometimes called micro vesicles) in the blood,” explains study co-author and Assistant Professor at the University of British Columbia Jonathan P. Little. Endothelial cells are the single layer of cells that line and protect our blood vessels. “Microparticles are small vesicles that get released from cells when they are inflamed or damaged, so finding an increase in endothelial microparticles tells us that the endothelial cells that line our blood vessels experienced some damage and inflammation when glucose spiked.” Though he says that the increase in markers of blood vessel damage was temporary, the long-term impact remains unclear. “We know that these endothelial microparticles are elevated in conditions such as heart disease and type 2 diabetes, which is why we were interested in measuring them,” he explains.

Besides the potential for blood vessel inflammation, Little also cautions that the metabolic adaptations your body experiences on the keto diet means that you’re relatively glucose intolerant, so a meal (or day) of high carb eating might not be the best plan. “When you adapt to a ketogenic diet, you become a proficient fat burner and this occurs at the expense of carbohydrate metabolism. It probably isn’t the best thing for your metabolism to throw carbohydrates (especially high glycemic index carbs in high amounts — such as a glucose tolerance test drink that we used or a big ‘cheat meal’) into the mix if you are on a ketogenic diet,” he says.

Devine agrees and shares concerns about the long-term risks of this approach. “The benefits from a ketogenic diet are a one-way street,” she says. “You can get away with a high intake of dietary fats (including saturated fats) without the negative impact on risk factors for cardiovascular disease (specifically, particle size of LDL and triglycerides) only when these foods are not consumed in conjunction with refined carbs and sugars,” explains Devine. In her view, going back and forth will cause more harm than benefit over time. “I stress the importance of not cheating on a keto diet because once you start introducing sugars, the high-fat aspect can do more harm than good long-term.”

Experts also caution about the risks to your emotional health with keto cycling. “Starting keto with the idea that you can go off plan whenever you want and just jump right back in when you feel like it may be counterproductive for your weight, overall health and quality of life, explains Spritzler. Devine also notes that chronic yo-yo dieters may become less successful over time. In her experience, each keto hiatus can become longer and longer and as a result, it’s likely you’ll put the weight back on. At that point, the hurdles start to feel insurmountable, she says.

What’s the healthiest way to try keto cycling?

Despite the concerns, if you want to give keto cycling a try, experts recommend cycling in healthful sources of carbs instead of those craveable, heavily processed refined or sugary carbs. Think sweet potatoes, beans, milk and fruit over muffins, rolls and chips.

It’s also a good idea to make a plan for your carb-heavy days so you get the most benefit. For example, Spritzler says you might eat them on a workout day. “Pay attention to how you feel on the days you eat more carbs,” she says. Some questions she suggests asking yourself: “Do your energy levels drop or soar? Are you happier and satisfied or anxious and hungry? Does your sleep improve or worsen?” Pay attention to your answers. “If you feel better off eating carbs occasionally and it doesn’t seem to interfere with your weight, keto cycling may be a good fit for you. On the other hand, many people do seem to benefit from staying consistently keto or alternating keto with low carb (around 30-60 grams of net carbs per day),” she explains.

Whether you add in those higher carb days or not, your keto diet should focus on other principles of healthy eating. Devine says to emphasize whole foods, quality proteins and heart-healthy unsaturated fats, such as olive oil, avocado, nuts, seeds and fatty fish instead of processed saturated fats, like cheese and processed meats. Spritzler agrees that the focus should be on minimally processed foods and she suggests this simple framework: Consume adequate protein (3-6 ounces) at every meal, include vegetables at most if not all meals, and eat enough to feel full but not stuffed.

Is keto cycling right for you?

The prescriptive nature of total carb abstinence may be appealing to some, but for others, can feel unnecessarily rigid. It’s important to get clear on where you fall in the spectrum and use that to guide your dietary decisions. Whether you’re trying to lose weight or just get healthier, it also makes sense to think about the foods you enjoy and the way you like to cook and then pick a plan that lines up with your food and lifestyle values. Be real with yourself and identify some non-negotiable foods. If pasta is one of them, keto cycling might be preferable to keto, but you might want to try another approach altogether.

Remember that the keto diet isn’t the be all end all — even for weight loss. As Kevin C. Maki, co-author of the National Lipid Association Scientific Statement points out, the long-term health impact is unknown. “While ketosis may have some benefits for reducing appetite, it may not be necessary to go to such extreme levels of carbohydrate restriction to lose weight and experience some of the other benefits, such as improving blood glucose excursions and triglyceride levels,” says Maki, who’s also an Adjunct Professor of the Department of Applied Health Science at the School of Public Health at Indiana University, Bloomington Indiana. He acknowledges that a keto-type diet for a limited period of time may work well for some people, but also points out the issues with long-term compliance. “Our general view is that most people would be better off focusing on regular exercise (e.g., walking) and consuming a high quality diet that emphasizes fruits, vegetables, whole grains, nuts, seeds, legumes, seafood and non-tropical oils, such as a Mediterranean diet pattern.”

Dr. Suzanne Steinbaum, Director of Women’s Cardiovascular Prevention, Health and Wellness at Mount Sinai Heart, Fellow of the American College of Cardiology and American Heart Association, and spokesperson for the American Heart Association’s Go Red for Women campaign, is also in favor of the Mediterranean diet over the keto diet or keto cycling approach. She says the Mediterranean diet has been shown to reduce the incidence of heart disease by as much as 30 percent and that weight loss and better blood sugar management can be achieved by boosting your vegetable intake and cutting way down on your consumption of overly processed carbs and sweets.

No matter which approach you go for, remember that the idea is to adopt healthier eating habits — not just for the next few weeks or months, but for life, which is the real key to healthy and sustainable weight loss.


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I Spent 3 Weeks on the Keto Diet—Here’s What It’s REALLY Like

Rimma Bondarenko

If you’re reading this article you’ve probably heard something about the keto diet—the low-carb, high-fat way of eating that has been linked to better brain health and lower cholesterol, and of course weight loss (here’s what our nutritionist thinks of it).

Also known as the ketogenic diet, it was originally created in the early 1900s to treat epilepsy, but the diet has recently blown up. And so, after several of my friends couldn’t stop talking about how they lost weight, had more energy, and felt amazing, I decided to test the claims myself.

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I also was intrigued by what I’d read on the diet’s effects for folks with Type 1 diabetes (the kind you’re born with). My fiancé, Nick, has to deal with all the pin pricks and blood sugar crashes that come with having Type 1, and isn’t much of a dieter. But he decided to try the diet with me, and we gave ourselves a goal of three weeks—not forever, but long enough (I figured) to notice a difference.

Full disclosure: We had two totally different experiences.

The goal of the keto diet is to put the body in a state of ketosis, where the body is starved of carbs and sugar (traditional forms of energy) and has to begin breaking down fat for fuel.

Keto dieters are allotted no more than 20-50g of carbs per day, depending on their body weight, height, and lifestyle. I used a keto calculator app to determine that I should have about 20g net carbs a day, which is calculated by subtracting fiber from carbs (for example: a cup of eggplant has 4.8 carbs and 2.5g of fiber, so your net carbs would be 2.3g).

What We Ate

An extensive Google search revealed that many healthy foods we love and eat daily (such as yogurt, oatmeal, quinoa, beans, corn, and pretty much all fruit) were off limits. But, cheese, meat, ranch dressing, and green veggies all get a green light.

This feels really counterintuitive. What kind of diet lets you eat a double quarter pounder with cheese (sans bun), but not an apple?

Cooking Light’s Food and Nutrition Director Brierley Horton, MS, RD, is not a fan, so when I told her abut my plan, she suggested I give it a pass. “I’m cautious of any diet that eliminates entire food groups, such as fruit,” she explained, “because you won’t be getting the key nutrients your body needs. It’s not a sustainable diet for the long run.”

I ignored Brierley for the sake of journalism (sorry, Bri!), and got to cooking.

Step one: I prepped several keto-friendly recipes for the week, and went shopping. One day I made a sheet pan dinner with sausage, Brussels sprouts, onions, mushrooms and herb butter. Another, I made kale salad with chicken, macadamia nuts, and lots of Parmesan. For lunches, I ate things like tuna salad-stuffed avocado. And to satisfying my pasta craving, I cooked zoodles with meatballs and low-carb marinara sauce. For my mashed potato cravings, I subbed in mashed cauliflower with lots of shredded cheese.

During the diet I also enjoyed steak, fish, and chicken, with a regular rotation of veggies. And eggs, oh my God, I ate SO MANY EGGS.

Image zoom Jaime Ritter

Since things like butter and cheese weren’t “off limits,” eating on the keto diet was super flavorful, and finding options at restaurants wasn’t difficult at all (almost anywhere has protein and greens, or a salad with lots of cheese). A favorite of mine was the Five Guys bacon cheeseburger with a lettuce “bun.” I could feel Brierley cringing, but hey, it was at least delicious.

Our Weight Loss Goals

Here’s the thing: It really does work for weight loss—we both lost more than a pound a week, while counting no calories, and eating all the butter and fat we wanted (more than I wanted, actually). I lost about 3.5 pounds in the three weeks that I was on the diet (though I gained a bit back toward the end, as you’ll see) and Nick lost more than 5 pounds, as well as gaining some other health benefits, which I’ll talk about below.

How We Felt

I had heard the transition to ketosis was supposed to be a little rough, but my friends all said they felt amazing after being on it for a few days, so I was unsure how I was going to feel. Unfortunately, it was more than just a little rough.

For the first few days I constantly had the grossest sensation of grease covering my mouth. I brushed my teeth at least two or three times a day to get rid of it. I blame it on all the extra fat I was eating from sources like butter, cheese, eggs, ranch dressing, fatty meats, and mayo. I also felt like there was no way I was losing weight—all the fat and dairy I was eating made me feel super bloated (in hindsight, I think it was all of the sodium.)

Then there was the worst part: The keto flu. The transition to ketosis involved a major energy drain caused from carbohydrate withdrawal. Keto flu hit me like a truck on day 2 and lasted until about day 4. During that time I felt super tired, achy, and slightly drunk. I was so foggy at work, I could barely concentrate. Nick had keto flu around day 3, and it lasted until day 5.

Related: How to Safely and Effectively Come Off the Keto Diet from Shape

Our keto flu was coupled with intense carb cravings (after this diet, I truly believe the research purporting that carbs and sugar behave the same way as cocaine and heroin.) Let me tell you, we were SUPER fun to be around during that first week, and our text messages looked something like this:

Image zoom Jaime Ritter

And guys, the sugar and carb cravings were so, so real. I wanted a cake donut so badly I would have thrown a rock through a Dunkin Donuts if I’d had the energy, and don’t really even like them that much—I know what’s in them. Meanwhile, Nick was craving a smoothie. A smoothie! In the three years we’ve been dating, I’ve seen him eat fruit a sum total of two times.

On night three, I went to Bed, Bath & Beyond to pick up a wedding gift for a friend, and I saw an elderly man licking a soft serve ice cream cone. I had taken three steps toward him before I realized I was contemplating ripping it out of his hand, and knocking him down, just so I could take a bite. I had to turn around and leave immediately. I’m not proud of this.

I felt like an absolute monster, and immediately Googled “keto flu cures.” Turns out eating lots of potassium helps, as well as guzzling water, so Nick and I upped our intake of foods like avocado, leafy greens, and salmon, which helped tremendously (I didn’t threaten any more old men.)

How Nick Fared

Nick lasted the entire three weeks, and had great success on the keto diet. Not only did he lose 5.3 pounds, but he had a far easier time controlling his type 1 diabetes. During the three weeks, he barely had to take any insulin on top of his basal (read: baseline) amount, which is incredible.

The day after we finished, he went to the doctor to get his 3-month average blood sugar percentage tested—what’s called the A1C levels. Someone without diabetes will an a1c level of 5.7 or lower—but Nick’s usually hovers around 8 or 9, which isn’t great.

3 months ago, his A1C was an 8.6. He had it tested the day after we finished the keto diet, and it was 7.6—an entire point lower! That’s a huge deal for diabetics, and Nick credits a low-carb diet for the changes. He says he wants to stay on the keto diet because it’s helping him manage his diabetes better, plus he’s losing a good bit of weight on it.

How I Fared

I, on the other hand, did not last the entire three weeks—but, hear me out. I made it 20 days on the keto diet, but the final weekend I attended my best friend Holly’s wedding.

I had been a perfect low-carb angel the entire wedding weekend. I pushed my mashed potatoes to the side during dinner, limited my cocktails, and made sure to eat lots of fat (gross, I know).

But Holly’s mom made her wedding cake—a gorgeous lemon curd and vanilla bean cake that was better-than-bakery quality. You could smell the bright lemon and creamy vanilla from across the room, and I knew that I was toast. I tried to hold strong when our server brought us all out slices, until Holly’s mom asked if I was going to try a piece.

She had traveled all the way from Ireland for her daughter’s wedding, and made the cake herself, and I just couldn’t resist any more—nor did I want to! I thought about it and decided that life’s too short not to eat the cake at your best friend’s wedding. So I ate every glorious bite of that carb-y, sweet cake, and I had zero regrets.

…that is, until I got super sick the next day. Apparently, when you give up carbs and sugar for weeks and then dive head-first into a massive slice of cake, your body doesn’t like it.

I’ll spare you the details, but suffice to say if you’re coming off keto, tread lightly. Otherwise, you’ll suffer.

Despite ending on a low note, keto wasn’t all bad. I was down 3.5 pounds until I had the cake, though I still ended up losing 2.8 pounds.

Plus, the diet forced me to become way more conscious of what I was putting in my body. I now realize that before starting keto, I was eating way too many carbs.

Though I realize there’s room for an occasional bagel at breakfast or a slice of wedding cake in a balanced diet, I definitely think I’ll continue cutting back on my carb intake. It was amazing—and kind of scary—to see the effect that cutting out carbs—and reintroducing them—had on my body.

Not all carbs are bad (in fact, you need carbs to live), but I realize that I was eating too much of the processed junk. So even though Nick and I had two very different experiences on the keto diet, I think we will both continue to eat more leafy greens, lean protein (we need a break from all the beef), and slash our carb intakes. And I think Brierley will be happy to hear that, too.

The Keto Diet: Is It Worth a Try?

02 Jul The Keto Diet: Is It Worth a Try?

Posted at 07:00h in Hot Topics, In the News, Weight Loss by Toby Amidor

One of the most popular diets today is the ketogenic diet (AKA the keto diet). This diet has been around for quite some time and used to help epileptic children, but it has recently become the latest weight loss trend. Before you start filling your plate with fatty foods and drastically limiting your carbohydrates, here’s what you need to know.

Keto Diet 101
The Ketogenic diet is essentially a very low carbohydrate, moderate protein and high fat diet that puts the body into a metabolic state, known as ketosis. In a state of ketosis, the body no longer utilizes carbs (specifically glucose) as energy, but converts fat into called ketones in order to fuel the body. Once your body uses ketones for fuel, you are in a state called ketosis. Proponents of the plan claim ketosis can lead to many health benefits including weight loss, increased energy, and enhanced physical and mental performance.

What You’ll Be Eating
The general ratio of nutrients on the keto diet is:

  • Fat: 70% of calories
  • Protein: 25% of calories
  • Carbs: 5% of calories

On the keto diet, you’ll be eliminating grains (yes, even whole grains), fruit, starchy vegetables, legumes and sugar. Instead, you’ll be filling your plate with a lot of meat, leafy greens and other non-starchy veggies, high fat-dairy (think cream and butter), nuts and seeds, avocado, butter, coconut oil, and high-fat salad dressings. If you need a sweetener, you’ll have to rely on the low-carb options like stevia, erythritol (a type of sugar alcohol), and monk fruit.

The Risks
Some of the negative side effects of being in a state of ketosis include constipation, muscle loss, decreased energy, bad breath, leg cramps and even the “keto flu,” which often occurs in the first few weeks of following the diet. Headaches, nausea, trouble focusing and sleeping, and also often reported.

While in ketosis, you also run the risk of developing ketoacidosis, which is an acidic state for your body to be in and over the long-term can lead to headaches, fatigue, irritability, and could potentially even lead to organ damage and become deadly.

It’s important to remember that the diet was originally developed as a medical intervention for epilepsy done under the supervision of medially trained professionals. With such large restrictions in what you can eat, you also run the risk of becoming deficient in key vitamins and minerals, so it is recommended that you take a multivitamin and mineral supplement while following the plan.

Another question that is often raised is long-term effects. However, there are not human studies that have examined the long-term effects of following a keto diet, or the long-term effects of being in a state of ketosis.

My Take
While weight loss seems to a major benefit to following this plan, when you cut out numerous food groups you are not sufficiently meeting the needs of your body to keep it healthy. In addition, severely cutting out major food groups also makes it difficult to stick with long-term, and when it comes to making lifestyle changes, sustainability is key.

While both good and bad types of fats are encouraged on the plan, a high intake of saturated fat is encouraged, which can raise blood cholesterol and the risk of heart disease. If you’re looking for a quick fix for fast weight loss, keto will work—but mind my words that you’ll most probably be back to your old eating patterns in no time (with the weight right back to where you started).

TELL ME: Have you tried the keto diet? What was your experience?

Ketogenic diet: What are the risks?

Fad diets often come with big promises of weight loss and optimum health, but at what risks? University of Chicago Medicine Ingalls Memorial dietitians say the ketogenic or keto diet, which has gained popularity in the last several years, is extremely strict and difficult to maintain.

Rachel Kleinman, RDN, LDN, clinical dietitian at Ingalls, said the keto diet is primarily used to manage seizures in children with epilepsy. Research on the diet’s effectiveness in treating obesity or diabetes is limited.

Ketosis is a metabolic adaptation to allow the body to survive in a period of famine. Your body will break down ketone bodies, a type of fuel the liver produces from fat, instead of sugar or glucose from carbohydrates.

To achieve ketosis, the diet requires you eat 75 percent of your calories from fat, compared to 20-35 percent normally. It also requires 5 percent of calories from carbohydrates, about 20-50 grams per day, and 15 percent of calories from protein. Kleinman said it takes about 72 hours for ketosis to kick in. “It’s really an all or nothing diet,” Kleinman said.

People following the keto diet should be eating foods like fatty fish, eggs, dairy, meat, butter, oils, nuts, seeds and low-carb vegetables. “Fat bombs” like unsweetened chocolate or coconut oil can help people reach their daily goals for fat intake. Keto-compliant foods like red meats and nuts can be costly, Kleinman said. Keto-branded products like keto coffee and other supplemental products are also both costly and unnecessary.

Wellness Dietitian Mary Condon, RN, LDN, said the keto diet may result in weight loss and lower blood sugars, but it’s a quick fix. “More often than not, it’s not sustainable. Oftentimes weight gain may come back, and you’ll gain more than what you lost,” Condon said.

Condon said you should always consult your primary care doctor before starting any new diet.

“If you are on diabetic medication that causes low blood sugar, those meds may need to be adjusted within a few days,” Condon said. “There are heart-healthy sources of fat, however if that person is not educated on heart-healthy sources of fat, they may consume excessive amounts of saturated fats that can increase your risk of heart disease,” Condon said.

The keto diet could cause low blood pressure, kidney stones, constipation, nutrient deficiencies and an increased risk of heart disease. Strict diets like keto could also cause social isolation or disordered eating. Keto is not safe for those with any conditions involving their pancreas, liver, thyroid or gallbladder.

Kleinman said someone new to the keto diet can also experience what’s called the “keto flu” with symptoms like upset stomach, dizziness, decreased energy, and mood swings caused by your body adapting to ketosis.

Both Condon and Kleinman said they wouldn’t recommend the keto diet to their patients because it is ultimately not realistic or sustainable. The diet restricts fresh fruits and vegetables, whole grains and low fat dairy that can help with long term weight loss and overall health.

“There’s not one diet that’s good for everyone,” Kleinman said. “Do your research, consult a dietitian, discuss with your doctor, and make sure you’re being safe.”

Call the Health and Nutrition Experts at UChicago Medicine Ingalls Memorial at 708-915-8850 to discuss nutrition counseling programs offered to meet your personalized needs.

Is keto diet bad?

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