Science Behind the Probiotics

How to Choose the Right Probiotic for You

September 5, 2018 2:00 PM CDT

9/5/18 2:00pm

As you make your way to the probiotic aisle at the store or browse the internet for options, you begin to realize: there’s a lot out there!

The Probiotic market is flooded with products and brands eager to capitalize on the benefits behind probiotics.

So how do you pick the right probiotic for you? And how do you determine which products are backed by scientific research?

Let’s jump into it!

Due to the unique characteristics of probiotics and their diverse benefits, regulatory requirements for probiotics depend on intended use and can be confusing. This makes it all the more important for consumers to do their homework and be able to identify quality probiotics.

The following criteria are good things to look for when evaluating a probiotic label:

  1. Brand
  2. CFU – the number of living microorganisms
  3. Expiration Date
  4. Storage information
  5. Match the species and strain of probiotics to the benefit

1. Brand

Look for a brand that is backed by scientific research. You may think that all studies conducted by drug companies are naturally biased but many companies sincerely value health and wellness and invest in clinical research to substantiate their claims. A company truly dedicated to research will invest in studies that are randomized, double-blind and placebo-controlled.

Research a brand to see if they are the real deal:

  • Visit their website to find evidence of research
  • Look for the above keywords along with probiotics that are “clinically proven”
  • When possible, confirm a product is manufactured according to good manufacturing practices.

2. CFU – the number of living microorganisms

CFU stands for Colony-Forming Units. This number represents the best estimate of the number of living microorganisms in a sample. This is highly important as probiotics are living things and would only be considered a probiotic if they enter the intestinal tract alive.
But a higher CFU does not necessarily mean a superior product.

While a higher CFU is generally a good indicator, life is about balance and this is no different with probiotics. Your body needs the right amount of the right strain.

The number of colony forming units you need depends on your health and intended use of the probiotic. If you are in good health and plan to use probiotics for daily support, aim for 10 billion CFUs. If you are to support your health and think you need a higher dosage to start, you may want to seek out a supplement with 15-50 billion CFU’s. As always, consider safety first. Probiotics are safe for most people, but talk to your doctor first if you have any underlying illness or have a question about the use in the very young.

3. Expiration Date

The expiration date is just as important as the number of living organisms. After all, the CFU claim on the label means nothing if the probiotics are dead by the time they reach you.
Be wary of a product that only provides a “time of manufacture” or states “viable at time of manufacture”. You do not care if the probiotics are alive at production, you want them alive when they get to you.

Trust a product that has an expiration date or reads “viable through end of shelf life” or even “live cultures guaranteed”.

Pro tip: Pay attention to the expiration date when you bring your product home. You won’t get any benefit from a probiotic that has expired and died.

4. Storage Information

Since our probiotics are living things, it is important to store them in a suitable environment that will keep them alive. While probiotics remain in a dormant state until ingested, moisture and heat will drastically reduce their shelf life.

A dark, cool and dry place (ideally refrigeration) is always a welcomed environment to a probiotic and is guaranteed to maximize their shelf life. However, some probiotics are shelf stable and can survive under room temperature conditions. Reference the package label for specific storage instructions. Even for those products that are room temperature stable, once purchased, keeping cool is always the best route.

Shelf life can also be increased by a company’s choice of packaging. Amber glass provides protection from harmful UV rays and included desiccant packets will minimize moisture. CSP bottles, also known as Stability Shield™ (pictured right), offer even greater stability as the whole container is composed of a desiccant material.

Pro tip: Keep your probiotics in its original packaging rather than a pillbox to keep them happy.

5. Species and Strain of Probiotics Present

Your microbiome is naturally composed of thousands of diverse strains that benefit your body. Why should your probiotics be any different? Look for a probiotic supplement with a diverse combination of strains.

No one strain can do it all!

Select a combination of strains that are clinically proven to provide the desire benefits you seek.

The most well-known and proven probiotics to look for are Lactobacillus and Bifidobacterium. A list of common probiotic strains and their reputed benefits can be found here.


The most effective way to optimize your probiotics is to nourish the environment in which they live – your body. You do this by eating a balanced diet and exercising regularly. Supply your body with the healthy fats, proteins, carbohydrates, fiber and prebiotics they need to grow the healthy bacteria in your gut.
Minimize processed foods and refined sugars, which can nourish the potentially pathogenic bacteria in your body.

As part of our series on digestive health, today we’re diving into the topic of probiotics. Our everything guide to finding the best probiotic for you is all about what these microorganisms are and the role they play in your digestion and beyond!

What are Probiotics?

When we think of bacteria, we often think about germs, sickness and disease. But the truth is your body is the natural home to trillions of microorganisms that are essential to your health and well-being. Consider this: there are approximately 10 single-celled microbes for every single human cell in your body, averaging a total of 2.2 pounds!

Probiotics are the live bacteria and yeasts that live in your body and keep your gut healthy. These friendly bacteria patrol your intestines and keep your digestive system running smoothly by helping digest food, destroying harmful pathogens, and producing vitamins.

Probiotics are especially helpful after a round of antibiotics, as these drugs kill both infectious and healthy bacteria. When healthy bacteria are killed off, the harmful bacteria flourish, often leading to diarrhea or other digestive troubles.

How To Choose The Best Probiotic For You

Having a healthy gut flora means an abundance for your health, digestion, well-being, and even beauty! As we saw last week, there’s ongoing communication between your GI and your brain, known as the gut brain axis. This means a healthy gut can benefit the regularity of your digestion as well as cognitive function like mood and depression, and even the health and appearance of your skin.

While more research is necessary to fully understand the benefits of different probiotic strains, we do know that not all probiotics are created equal. The Lactobacilli, for instance, live in our digestive, urinary, and genital systems and can be found in some fermented foods like yogurt. Bifidobacteria normally live in the intestines as lactic acid bacteria, and are also found in fermented foods. According to nutrition expert Alex Caspero, RD, “For certain conditions, you want to ensure you’re taking the strand that is most likely to benefit you.” Here’s a simple breakdown to help you determine the best probiotic for you.

L. Acidophilus

Best Probiotic for: Acne, Vaginal Health, Diarrhea

Here is one of the most widely recognized probiotics. L. acidophilus consumption has been steady since the 1920s when doctors would recommend acidophilus milk to treat constipation and diarrhea.

These microbes survive stomach passage and are able to colonize in the intestine. There’s good evidence looking at Acidophilus NCFM in treating vaginal infections. Other studies show that it has been demonstrated in humans to reduce problems associated with lactose intolerance and even decrease the risk of colon cancer .

However, it’s not just digestive woes that probiotics can help address. A clinical case series followed 300 patients who took a probiotic mixture of L. acidophilus and L. bulgaricus. They documented that 80% of acne patients had some degree of clinical improvement, particularly effective in inflammatory acne. Later, an Italian study involving 40 patients found L. acidophilus and B. bifidum supplementation produced better clinical outcomes in acne as well as better tolerance and compliance with antibiotics .

L. Rhamnosus

Best Probiotic for: Eczema

L. Rhamnosus is thought to be the most extensively studied probiotic in adults and children, and strong evidence shows that it colonizes the intestine. Gut flora is disrupted during travel, and healthy bacteria is killed off during a round of antibiotics. Rhamnosus GG has been found beneficial specifically for treating diarrhea associated with these cases .

Another exciting study found that this strain was also potentially beneficial in preventing eczema. The children of women who supplemented with it during childbirth were half as likely to develop atopic eczema by the age of four than the children of women who did not .

L. Plantarum

Best Probiotic for: Inflammation

In the gastrointestinal tract, L. plantarum can help regulate immunity and control inflammation. A 2007 study found that the probiotic could suppress an inflammatory response in the gut. Perhaps most significantly, a double-blind placebo-controlled study over four weeks concluded that L. Plantarum 299v provided effective symptom relief, especially of abdominal pain and bloating, in patients with IBS .

L. Casei

Best Probiotic for: GI support, Brain Function

Studies show some promising results with L. casei for digestive support and regulating diarrhea. One study on the effect of milk fermented by L. Casei strain DN-114 found that supplementation significantly reduced the incidence of diarrhea .

L. casei also made headlines when a study found it beneficial in relieving anxiety. The randomized, double-blind, placebo-controlled pilot study found supplementation with 24 billion units of the L. casei strain Shirota led to a rise in probiotics lactobacillus and bifidobacterium, as well as a significant decrease in symptoms of anxiety and depression .

Now let’s take a look at a separate class of probiotics, bifidobacterium.

B. Lactis

Best Probiotic for: Immunity

To boost the immune system, B. Lactis is a promising choice. One study had participants taking either a probiotic or a placebo for six weeks. At the end of this period, researchers measured antibody levels and found greater increases in antibodies of the B. lactis group than in placebo participants, concluding that this probiotic may help improve immune function . In addition, a 2009 study found that supplementation of the strain B. lactis DN-173 led to self-reported improvements in digestive comfort .

B. Longum

Best Probiotic for: Constipation, Brain Function

B. longum is one of the first types of bacteria to colonize our bodies at birth. These important microorganisms ferment sugars into lactic acid, helping to stabilize the acidity of the GI tract and inhibit growth of harmful bacteria. For a group of adults prone to constipation, taking a mix of B. longum BB536 with milk or yogurt for two weeks increased bowel movements .

B. longum is also one of the species researched for the role of probiotics in the gut brain axis. A report from University College Cork found in a study of healthy men that supplementing with B. longum 1714 caused stress levels to decrease and memory to improve .

B. Bifidum

Best Probiotic for: Immunity, GI support

Time, stress, diet, and antibiotics can all deplete the body’s supply of B. bifidum. Researchers found that these microbes help regulate the innate immune response, your body’s first line of defense against infection.

B. bifidum has also been shown to prevent intestinal pathogens or digestive disrupters from flourishing in the gut, essential in restoring the bacterial balance and optimizing digestion. Clinical research found it supports a significant reduction in IBS symptoms, an improvement in quality of life and even helps relieve occurrences of ulcerative colitis, a chronic inflammatory bowel disease. .

B. Breve

Best Probiotic for: Anti-aging

A pilot study found that B. breve was effective in increasing stool frequency in children with functional constipation. These researchers also found a positive effect in stool consistency and relief in abdominal pain, making B. breve a promising addition for easing digestive woes like constipation .

Other studies looking at the benefit of probiotics on skin ailments found a fascinating trend. B. breve B-3 could potentially be used to prevent photo-aging induced by chronic UV irradiation . This ability to mitigate the detrimental effects of UV exposure in sun damage is great news for keeping skin plump, hydrated, and youthful.

Not to be confused with streptococcal infections or the bacteria that causes strep throat, some species and strains of streptococcus have promising research on the benefits for health and well-being.

Streptococcus Thermophilus

Best Probiotic for: Skin Support

This probiotic displays antibacterial activity against harmful intestinal microbes, indicating a possibility to prevent diseases. A study on S. thermophilus in combination with L. casei and L. bulgaricus found reduced incidence of antibiotic-associated diarrhea with supplementation.

There is also promising research on this species for supporting skin. Ceramides are natural lipids that make up the surface of the skin structure. Depleted ceramide levels are clinically linked with dry and damaged skin. S. thermophilus was shown to have a beneficial effect on the level of ceramides in the barrier of the skin, which protects underlying tissue from infection, dehydration and chemicals. These skin-supporting microbes also act as antioxidants in the body, trapping reactive forms of oxygen that dry, damage and age the skin .

Buyer’s Guide

If you think supplementing with a probiotic is right for you, our nutrition expert Alex Caspero shares her tips on what you should know and look for when choosing the best probiotic supplement for your concerns.

What to Look For

Check expiration dates, make sure the bacteria is live, and look for CFUs (colony forming units) in the billions. Anything less isn’t as potent. A good brand specifies the amount of live organisms, and lists the exact strains used in their formula.

The label should also specify that the living microbes are viable through end of shelf life or best-by date rather than at time of manufacture to ensure the bacteria are still live when you take them and able to reach your colon. Quality trumps everything: Bargain supplements typically aren’t of good quality. Depending on strands, a good probiotic can cost anywhere from $25-$60.

How to Take AND Store

Make sure to keep probiotics away from moisture and heat, which can kill off some of the microbes. I recommend taking them on an empty stomach, ideally right when you wake up. You should always store supplements in a cool, dark place. Most strains of probiotics are fragile and should be protected from heat, so refrigeration is ideal. I recommend the probiotic Gut Instinct from HUM Nutrition for transparency and high quality.

How to Pick the Best Probiotic

A reader asked about choosing a probiotic supplement, so I went straight to an expert to learn what makes the best probiotic supplement.

Q: I want to take a probiotic supplement for better health. How do I know which are the better and stronger strains?

To me, this question is like asking what’s the best form of transportation. It depends on a bunch of things. The best probiotic (or means of transportation) in one situation is certainly not the best in another. And the best option today might not be a good choice next year.

Anthony Thomas

To be certain that we have a solid answer, I interviewed Anthony Thomas, PhD, director of scientific affairs at Jarrow Formulas. I recently met Anthony at a conference in which Jarrow Formulas sponsored a session. Anthony was the speaker, and I knew right away that he had the answers my readers wanted.

Trillions of bacteria set up home throughout our bodies. Most reside in our large intestines. Some of these guys do good while others do harm. If the balance of various types of microbes is thrown off, probiotics might help. Check out How To Throw a Dinner Party for Your Gut Bacteria, and scroll down a bit to see What are Probiotics?

Jill: Selecting a probiotic seems more complicated than buying a new car. What should people consider when looking for a probiotic?

Anthony: When selecting a probiotic, it’s critical to first identify why you’re taking it. It’s well recognized scientifically that the benefits of probiotics are specific to the strain, dose and condition, such as supporting immune function or women’s vaginal and urinary tract health.

People commonly ask for the strongest strains of probiotics, but that’s not a question that has an easy answer. More importantly, we need to ask which strains of probiotics have research to support their use for your specific concern. For example, are you looking to relieve digestive problems, or discourage vaginal yeast overgrowth or do you want a probiotic for something else entirely? Your answer helps determine the best option for you. Rarely are products interchangeable.

Given the plethora of commercial products available claiming to contain probiotics that support immune function, for example, I think it is first important to verify that the product contains genuine probiotic strains that have been shown in clinical research to support immune function and health.

Jill: So, what then should consumers look for on labels?

Anthony: An accurate strain designation is typically a combination of letters and numbers listed after the microbial genus and species. You might see something that looks like this: Lactobacillus rhamnosus R0011.

Even more commonly, you’ll see L. rhamnosus R0011.

All three elements need to be identified. Otherwise, you have no way of knowing what exactly is in your probiotic food or supplement, or if there is research to substantiate the organism as a true probiotic.

  • GENUS: Lactobacillus
  • SPECIES: rhamnosus
  • STRAIN: R0011

Thanks to Jarrow Formulas for sharing this terrific graphic

Jill: Do all yogurt brands have probiotics?

Anthony: No. Not unless they have been added to the yogurt and are present in adequate amounts at time of consumption. By definition, a probiotic must be alive when you swallow it, and not all yogurts have this, especially if not transported and stored with care and consumed before the best buy date. Additionally, just because a yogurt has live bacteria doesn’t mean the genus, species and strain is the one that has the effects that you are looking for.

Jill: This is getting very complicated. Can you share an example of a yogurt in the supermarket?

Anthony: The brand Nancy’s offers a number of probiotic yogurts that claim to support immune health. In addition to the yogurt starter cultures, these yogurts contain specific probiotic strains, such as Bifidobacterium lactis BB-12 and Lactobacillus rhamnosus LB3, that actually do have research to support immune function, hence substantiate the claim of support for immune health.

Choosing a probiotic supplement. This slide is from Anthony’s sponsored talk at a recent nutrition conference.

Jill: Since specific strains are appropriate for specific conditions only, how can consumers find out what they should take for their problems?

Anthony: Currently, there is no comprehensive guide to evidence-based recommendations for probiotics. But there is a clinical guide to probiotics available in the US that’s useful. You’ll find it at usprobioticguide, and it’s also available as an app. This is a nice resource for both healthcare practitioners and consumers to guide evidence-based usage recommendations of probiotics for a given health indication. The references to the research are also provided. There’s a similar guide for products available in Canada.

Jill: I’m picking up from this conversation that consumers have homework when it comes to selecting a probiotic.

Anthony: Yes! There is no one-size-fits-all for probiotics, and many products are marketed for a variety of health indications, but lack research to support their marketing claims. I encourage consumers to discuss their needs with their healthcare providers. A healthcare provider can help you pick a product that has documented research to support the claims.

Jill: Do you have any red flags to share?

Anthony: Not having much information about the manufacturer on the packaging is a red flag. The manufacture’s contact information should be available. Or at least, a website should be listed, and full contact information should be on the website. You should have a resource listed, so you can request more information, including research to support the product claims.

Another red flag is a product that claims live probiotics “at the time of manufacture,” which is often listed in small print. Steer clear of these. This purposely misleads consumers, as it inflates the quantity listed on the label and does not represent the number of live probiotics in the product at the time of administration. By definition, a probiotic must be alive and provide adequate amounts to realize a health benefit at time of administration – at the time that you consume it.

Jill: How long does someone need to take a probiotic supplement?

Anthony: If you’re taking a probiotic for a chronic health condition or for the prevention of a health problem, you’ll need to take your probiotic long term. That’s because administered probiotics don’t sustainably colonize the adult gut.

Jill: They’re just visiting?

Anthony: Yes. They’re temporary residents that interact with the microbial community and host cells during their transient stay and in transit through the gut.

Jill: Are the probiotic supplements that require refrigeration better than shelf-stable supplements?

Anthony: No. The efficacy of probiotic supplements is inherent to the strain(s) used and quality of manufacturing. However, increasing temperatures generally have a negative impact on viability and functionality of probiotics over time. It’s a good idea to refrigerate probiotics whether the product claims to be shelf stable or not.

Bottom line: Probiotics can be quite beneficial. Do your homework to find out which products contain the strains with research to support the specific effect you are looking for. Just like taking a vitamin C supplement when you really need vitamin D won’t help, taking the wrong probiotic product won’t help you either. This is true even if it helped your friend with a different health concern. Finally, store the product properly, and consume it by the “Best Used Before Date.”

For more information, check out the International Probiotic Association (IPA), the International Scientific Association of Probiotics and Prebiotics (ISAPP), and And for a brief discussion about fermented foods and probiotics, take a look at the National Dairy Council website.

More about Anthony: Anthony Thomas, PhD is the director of scientific affairs at Jarrow Formulas. He evaluates and manages research activities related to product formulation, including dosing and usage recommendations to reflect scientifically supported benefits for health and product use in clinical studies. His primary research interests have focused on the influence of dietary and lifestyle factors on the pathogenesis of several disease states. Anthony has authored and co-authored multiple peer reviewed scientific manuscripts and served as a referee with relevant expertise of nutrition for multiple scientific journals.

A probiotic primer

An imbalance in the gut microbiota is believed to contribute to a number of health problems, particularly gastrointestinal issues, as well as immune dysfunction and infections. The bacterial balance can be disrupted by medical conditions, emotional and physical stress, and, most notably, use of antibiotics, which destroy the good bacteria along with the bad.

Probiotics help tip the balance back in favor of the good bacteria. In doing so, they may provide some relief if you have irritable bowel syndrome (IBS), ulcerative colitis, acute infectious diarrhea, and diarrhea associated with antibiotic use or Clostridium difficile (C.diff) infection. They also can boost your immunity, fight inflammation and potentially have beneficial effects on cholesterol.

Choosing a probiotic

To be a true probiotic, a product must contain live and active bacterial cultures, and it should indicate as much on its packaging.

A general recommendation is to choose probiotic products with at least 1 billion colony forming units and containing the genus Lactobacillus, Bifidobacterium or Saccharomyces boulardii, some of the most researched probiotics. But you may have to delve deeper, as each genus of bacteria encompasses numerous strains that produce different results.

For example, yogurt is made with two “starter” bacterial cultures — Streptococcus thermophilus and Lactobacillus bulgaricus — but these bacteria are often destroyed by your stomach acid and provide no beneficial effect, Dr. Cresci explains. Some companies, though, add extra bacteria into the product, so check the labeling and choose products with bacteria added to the starter cultures, she advises.

“I’d probably stay away from store brands and pay a little extra for the name brand that’s been studied,” Dr. Cresci adds. “Ideally, look for a product that’s been tested for whatever you’re looking to address. It might say it helps with IBS, but you wouldn’t take that same product if you were taking antibiotics. You would want a product that helps with immunity. That’s where a lot of people get confused.”

Some people prefer probiotic supplements over foods, but Dr. Cresci notes that probiotic foods are a better choice. In particular, fermented foods — like yogurt, kefir (a yogurt-like beverage), kombucha (fermented black tea), sauerkraut (refrigerated, not shelf-stable), kimchi (made from fermented cabbage) and tempeh and miso (made from fermented soybeans) — provide a nourishing environment in which healthful bacteria thrive and release an important byproduct: short-chain fatty acids.

“They have beneficial effects on your immunity, inflammation and cholesterol,” she says. “Go for foods first, but there’s always a niche for the supplements, like if you need a certain strain of bacteria that’s not available in a food source.”

Feed your bacteria

The probiotic industry is booming, but the benefits of probiotic products and the quantity of viable bacteria they contain can vary. So, instead of adding bacteria from an outside source, you might be better off consuming prebiotics, like fermentable fiber, which support your own beneficial bacteria, Dr. Cresci says. Good dietary sources of prebiotics include dried beans and other legumes, garlic, asparagus, onions, leeks, certain artichokes, green bananas and wheat. Prebiotic supplements are available, as well.

“What bacteria like is fermentable fiber,” Dr. Cresci explains. “I don’t know that you need a probiotic if you’re eating a healthy diet. If you want to try a one-size-fits all to improve your gut health, it’s really your diet and including prebiotics. What we eat is probably the biggest influence on our gut microbiota.”

How to get started with probiotics

Think you want to give probiotics a shot? Here are Dr. Cresci’s take-aways to help you navigate them:

● Probiotics are generally recognized as safe, but they’re typically not recommended if you have a compromised immune system. Ask your physician if probiotics are right for you.

● It may take some trial and error to find the probiotic that works for you. If you notice no benefits from one product after a few weeks, try a different one with a different strain of bacteria.

● Probiotics may cause bloating and gas, as well as changes in your stool patterns — all indications that the product is working, Dr. Cresci says.

● Prebiotic foods help your good bacteria flourish. Include beans, asparagus, onions, green bananas and other fermentable fiber sources in your diet.

This article originally appeared in Cleveland Clinic Men’s Health Advisor.

Probiotics have become buzzy in recent years: Celebrities including Lauren Conrad and Anna Paquin have been spotted carrying bottles of kombucha, a probiotic-containing fermented tea, and the probiotics market has been growing rapidly as more people pursue better health by taking probiotic supplements. Prebiotics are attracting notice too, but you may still be unsure of what exactly prebiotics and probiotics are. Here’s what you need to know about them to decide whether taking supplements is right for you.

First things first: What are probiotics, and what can they do for me?

Probiotics are live microorganisms that are thought to have health benefits, as the National Institutes of Health (NIH) reports. These bacteria and yeast are believed to help populate our guts with beneficial microbes, according to Mayo Clinic, and can be found in fermented or unpasteurized foods including yogurt, kefir, sauerkraut, and kimchi, as well as, yes, supplements.

Remember, while bacteria gets a bad rap, not all bacteria is bad: As New York City-based certified dietitian-nutritionist Gina Keatley tells Allure, plenty of microorganisms, including probiotics, actually help your body function. “Probiotics may help stabilize the protective barrier in our gut so bad microorganisms don’t take root, stimulate the immune response, and aid in production of vitamins, such as vitamin K,” she says. Sonya Angelone, a registered dietitian and Academy of Nutrition and Dietetics spokeswoman, adds that while we have more to learn about the role of probiotics, beneficial bacteria is understood to help crowd out harmful bacteria in our bodies. This good bacteria may also help lower cholesterol, aid in reducing colds and acute respiratory infections, and reduce the occurrence of vaginal yeast infections, she says.

What are prebiotics, and why do they matter?

The term “prebiotics” is often thrown around when probiotics are mentioned, and they’re related to probiotics in a sense. According to Angelone, prebiotics are complex sugars that we don’t digest but that are used as fuel by bacteria — including probiotics — that’s already in your gut. Registered dietitian-nutritionist Beth Warren, founder of Beth Warren Nutrition and author of Living a Real Life with Real Food, explains that you can think of prebiotics as food for probiotics. You can get prebiotics from foods including asparagus, bananas, garlic, and onions, she says.

Getty Images

Should I take probiotics as a supplement?

Given that you can get probiotics from the food you eat, you don’t necessarily need to take a supplement, and Keatley says she prefers food sources of probiotics to supplements. However, she adds that “There are times when you really need a boost.” One example might be during or after a course of antibiotics, as long as you have your doctor’s OK, since antibiotics kill both good and bad bacteria: “Seeding your gut with good bacteria can lay the groundwork for a faster recovery and less constipation and diarrhea,” Keatley points out. Angelone echoes Keatley’s emphasis on food sources of probiotics, but also says that supplements can also play a useful role in “maintaining a healthy gut bacteria colony.”

According to the NIH, probiotic supplements contain many microorganisms that are the same as or similar to the ones that naturally live in your body, but there’s still a lot of research to be done on probiotics and how they work. It’s important to keep in mind that not all probiotics have the same effects and that taking probiotics isn’t a guarantee of better health. And while they’re generally safe for healthy people to take, with side effects being limited to mild digestive discomfort, they could interact with certain medications or pose health risks to people with underlying medical problems — that’s why it’s smart to talk to your doctor before getting started with a supplement.

What should I look for in a probiotic supplement?

Unless you know that your body is lacking in a particular type of probiotic, you should just look for broad-spectrum probiotics that contain a mix of different strains of bacteria, Warren says: “We have billions of bacteria in our gut, so by taking a supplement with a range of different strains, you will ensure you are not overdoing or missing one type.” Keatley also stresses the importance of finding a supplement with a diversity of bacteria strains to keep overgrowth of any one strain in check. “Providing too much of an advantage to one strain of probiotic may push out another strain we didn’t know was important until it’s too late,” she points out.

How to Find the Best Probiotic for You

Photo: LIgorko / Getty Images

These days, there are a lot of people taking probiotics. And considering they can help with everything from digestion to clear skin and even mental health (yup, your gut and brain are definitely connected), it’s easy to understand why they’ve become so popular.

Because there’s a huge variety of probiotic products available on the market, many people struggle to find the right one for them. “There are many different strains of bacteria in different combinations within different probiotic supplements,” explains Brooke Scheller, a clinical and functional nutritionist. “For example, a probiotic may contain a single strain of bacteria or many. It may also contain other vitamins, minerals, or other ingredients that may tout health benefits,” she says. There are many different dosages, delivery systems (powder, tablets, capsules), and formulations (refrigerated vs. shelf-stable), and some probiotics also contain prebiotics, which basically act as fertilizer for the probiotics. (Related: Why Your Probiotic Needs a Prebiotic Partner)

What’s more, there’s still a lot more to learn about the microbiome and probiotics, in general. “Truth be told, the research area of probiotics and health is still pretty much in its infancy,” says registered dietitian Kate Scarlata. Research is growing in the area of gut microbiome daily-but it is much more complicated than first thought.” With all these options and major gaps in the available information, where are you supposed to start? Here, gut experts narrow it down to three simple tips for picking the right probiotic for you.

Step 1: Read the fine print.

Finding the right probiotic for you starts with reading the label. The most important elements, according to Samantha Nazareth, M.D., a double board-certified gastroenterologist:

CFU: This is the number of “colony forming units” present in each dose, which are measured in the billions. And while more isn’t always better, “you want at least 20 to 50 billion CFU,” says Dr. Nazareth. Just for reference, a very high dose is 400 CFU, which most experts agree is not necessary unless your health care practitioner specifically recommends this for you. It’s also important to check for the guaranteed CFU upon expiration, which should be listed clearly. “Some products only guarantee the CFU number at the time of manufacturing, therefore will be less potent by the time the product reaches your home,” she says.

Method of delivery: “The probiotic needs to be able to survive the acidic environment of the stomach and reach the intestine,” explains Dr. Nazareth. This can be optimized through the way you take the probiotic and what’s included in the formula. “Some delivery systems to consider are time-released tablet/caplet, capsules with an enteric coating and/or microcapsules, and ones that contain prebiotics and the optimal combination of probiotics,” says Lori Chang, a registered dietitian with Kaiser Permanente in West Los Angeles.

Species of bacteria: You want to look for the proper species for the condition you are treating, says Dr. Nazareth. More on that below.

Third-party testing: Lastly, it’s important to remember that probiotics are an unregulated supplement. “Find out whether there is third-party data verifying the potency, purity, and effectiveness of the product,” suggests Dena Norton, a registered dietitian and holistic nutrition coach. “Remember that dietary supplements aren’t regulated, so you can’t necessarily just trust the claims on the label.” Check out AEProbio, a site that has compiled research on specific brands of probiotics available in the U.S., recommends Scarlata, and an NSF seal is always a good marker to look for.

Step 2: Be specific.

Experts agree that this is the most important factor to consider in choosing a probiotic. “You should absolutely choose a probiotic based on what you are looking to address,” says Chang. “Because strain specificity will impact outcomes, it is important to consider that one strain that works for one condition will not necessarily be effective for other conditions.”

And though this may come as a surprise, it’s not recommended to take a probiotic *just because.* “Not everyone needs a probiotic,” says Dr. Nazareth. (If you’re not having symptoms and you just want to improve your gut health overall, try adding some fermented foods to your diet.)

That’s because issues that can be treated with probiotics stem from specific imbalances in the amount of certain bacterial strains, according to Elena Ivanina, M.D., a gastroenterologist at Lenox Hill Hospital. “Therefore, if someone decides to supplement a particular strain of Lactobacillus, but they already have enough of that strain in their gut and their disease does not stem from a lack of Lactobacillus, then they will not have a response.” Makes sense, right?

While this isn’t necessarily an exhaustive list, Drs. Nazareth and Ivanina recommend following this quick research-based guide to which strains to look for to help with various issues:

General Gut Symptoms and Digestive Health: Bifidobacterium species such B. bifidum, B. longum, B. lactis, and Lactobacillus species such as L. casei, L. rhamnosus, L. salivarius, L. plantarum. You’ll find both species in Ultimate Flora Extra Care Probiotic 30 Billion.

Lactose Intolerance: Streptococcus thermophilus can help you digest lactose.

Antibiotic-Associated Diarrhea: Saccharomyces boulardii and Lactobacillus acidophilus and Lactobacillus casei.

Ulcerative Colitis: VSL#3 and E. coli Nissle 1917 are good options.

Bacterial Vaginosis and Yeast Overgrowth: Lactobacillus species, such as L. acidophilus and L. rhamnosus.

Eczema: Lactobacillus rhamnosus GG can reduce risk of eczema.

Step 3: Be open to trial and error.

Every person’s microbiome is different, which means what worked for others might not work for you. “What you eat, whether you were born by C-section or vaginally, what antibiotics you have been exposed to, and whether or not you have ever developed food-borne illness are just some of the many factors that impact your gut microbiome,” explains Scarlata. And while research can help you determine which strains to take at which dosages, there may still be several different formulations to choose from.

Once you’ve selected a probiotic to try, know that it could take up to 90 days to notice an improvement, according to Dr. Nazareth. It’s also important to note that digestive problems could worsen when you first start taking probiotics. “If this occurs, you may need a smaller dosage with a gradual increase,” she says.

Plus, lifestyle factors, such as overuse of prescription antibiotics, emotional stress, other prescription medications, alcohol consumption, smoking, and poor sleeping habits, can have an impact on how well your probiotics are working. Chang says that probiotics need the right environment (in this case, a healthy body) to colonize.

If you’ve tried a probiotic after following these steps and it doesn’t seem to be working for you (or you just want some extra guidance in choosing one), head to your doctor (or a dietitian) to get a recommendation. “Have a thorough discussion with your doctor to make sure you are taking the appropriate bacterial strain for the appropriate reason,” advises Dr. Ivanina. “Then, follow up after taking the probiotic to make sure it is having the intended effect.”

6 Things to Look For When Buying a Probiotic

Probiotics are HOT right now. A quality probiotic can help to seed your gut with healthy and hearty bacteria that benefit you in so many ways – from helping to balance your digestion to improving the function of your immune system.

But there are so many products out there (and so many confusing terms like CFU, strains and delayed–release). So how can a consumer know what to look for when buying a probiotic? Here are 6 things to look for when you’re at your local probiotic shop:

#1 Multiple strains

Different strains of bacteria provide different benefits to the body. And studies have shown that multi-strain probiotics are more effective than single-strain probiotics! advanced gut health probiotic was crafted with a whopping 15 strains that mimic the balance of Lactobacilli and Bifidobacteria found in the gut. Each of the 15 strains was carefully chosen for whole body health. While we’re on the topic of strains, make sure that the strains are coded – this shows that the company is able to track the exact origin of the strains that they use. We use coded strains in advanced gut health probiotic, and we can tell you with certainty that they are human, non-GMO, and do not come from animals, like rats (we’re serious).

#2 Balanced Formula

Unlike many formulas that rely heavily on one or two strains of bacteria (like L. acidophilus and L. rhamnosus) with a fairy dusting of other strains in for label appeal, advanced gut health probiotic contains a balanced formula of 15 strains.

#3 Potency, CFU and Guarantee

CFU stands for colony forming units, and is the measure of how potent a probiotic is. You can find probiotics in CFUs ranging from 2 billion to 100 billion. Look for a probiotic that guarantees CFU at expiry. This means that it will contain at least the amount of bacteria promised on the label. Also, many probiotics can contain media and unhealthy cells. The strains in advanced gut health probiotic are triple-cleaned to ensure that toxins and weak cells are removed and only the strongest and fittest remain. advanced gut health probiotic is available in two strengths: 15 billion and 50 billion CFU. And the potency is GUARANTEED up to the time of expiry.

#4 Allergen-free

Unlike many probiotics on the market, which can contain allergens like dairy, fish, bovine, crustaceans, soy and wheat, advanced gut health probiotic is free from GMOs and allergens like wheat, gluten, dairy, soy, peanut, tree nuts, sesame, fish, eggs, corn, sulphites, shellfish and mustard. Boy, that was a mouthful.

#5 Capsules

Capsules are important, because they get the bacteria in your probiotic to where they need to go! Some probiotics on the market are housed in enteric-coated capsules. But enteric-coated capsules can contain plasticizers and phthalates. advanced gut health probiotic is encapsulated in a vegan, plant-based delayed-release capsule – that reaches the gut a full 45 minutes after standard capsules and has been shown to deliver up to 10x the bacteria to the gut – that contains no plasticizers or chemicals, thank you very much.

#6 Packaging and shelf stability

Many probiotics (even the shelf stable ones) are packaged in bottles. But every time the bottle is opened, the probiotics get exposed to humidity and ambient air, which can degrade them over time. advanced gut health probiotic is shelf stable, and was thoughtfully packaged in a blister pack, which protects each capsule from damaging humidity. (And for all of you nutrition geeks who are still reading, you’ll be happy to know that no heat is used in the blister packing process.)

The cherry on the top is that we test the CFU of advanced gut health probiotic AFTER all of these steps have been taken, which ensures that you are getting the most live, potent and tenacious bacteria delivered to where they need to go – your gut!

So if you’re looking to seed your gut with the heartiest and healthiest live bacteria, look no further than advanced gut health probiotic. Every detail of advanced gut health probiotic’s formula and delivery process has been carefully considered to ensure that MORE potent bacteria gets to your gut!

Should you take probiotics?

Updated: August 20, 2019Published: April, 2015

The “good bacteria” may help healthy people but aren’t formally recommended.

Probiotics are “good” bacteria touted to help maintain digestive health and boost the immune system. You can take them in a dietary supplement or get them from food sources, such as yogurt. But should you? They can be helpful in some cases, but we still need more studies to tell us if and when they are safe and effective for older adults.


Microbes in the lower intestinal tract help us digest food, fight harmful bacteria, and regulate the immune system. But sometimes an imbalance of microbes occurs, leading to diarrhea and other health problems.

When the gut becomes unbalanced with unhealthy levels of certain bacteria, probiotics can help restore the balance. They’ve been shown to secrete protective substances, which may turn on the immune system and prevent pathogens from taking hold and creating major disease. But we are still learning to understand how probiotics may promote health.

Some studies that suggest if you take a probiotic while taking antibiotics, you’re less likely to get diarrhea caused by the antibiotic. Probiotics taken as a supplement may also reduce the number of colds you’ll have in a year.

Probiotics are commonly used to reduce gastrointestinal symptoms that are not due to acute illness, such as gas, bloating, and constipation. But we need more studies to determine who will get symptom improvement, particularly in older people.


Many types of probiotics are on the market. Some have been well studied, and some haven’t. One theoretical risk of probiotics is if someone has an immune system weakened by illness or medication, that person could get sick from probiotics.

Another concern about probiotics is that they’re considered dietary supplements, not drugs. As a result, the FDA doesn’t monitor the manufacture of probiotics. It’s not clear if probiotics that can be bought at pharmacies and health food stores are high-quality products. It’s even possible that some lower-quality products may not even contain the probiotic bacteria that are listed on the label.

Plain Greek yogurt is a good source of probiotics. Sweeten the taste with fresh berries, which are rich in antioxidants and fiber.

Image: Thinkstock

The best food sources of probiotics

Supplements aren’t the only way to get a daily dose of probiotics. There are many foods loaded with these cultures of good bacteria. The top sources include

  • yogurt, especially plain Greek yogurt
  • kefir, a tangy dairy drink
  • fermented vegetables such as pickles or sauerkraut.

Trying to get probiotics from food sources alone can be tricky. Food manufacturers are not required to show a specific dose of a specific probiotic, so they don’t. You might have a more consistent dose in a supplement, but it’s best to speak with your doctor before beginning any probiotics regimen.

What you can do

Don’t start taking probiotics without talking to your doctor or pharmacist about whether probiotics might help you. People who have immune deficiency or are being treated for cancer should not use probiotics without a doctor’s okay.

The most common species of bacteria used in probiotics (among a potential 3,000 or so) are species of Lactobacillus or Bifidobacterium. The bacteria are usually freeze-dried (but remain alive); when you take the supplement, they warm up in your digestive system and become fully active. You can find probiotic supplements in most drugstores and supermarkets. They come as capsules or tablets to swallow and as loose powder to sprinkle on food. You’ll want a product that explicitly states a “sell-by” date. Dosages vary by product, so no general dosing recommendation can be made. However, common dosages for adults range from five billion to 10 billion colony-forming units per day. Take just one dose of probiotics per day.

Some people may experience loose stools in the first few days of taking probiotics, but this goes away. Taking probiotics at the end of a meal may help to reduce the symptoms. 

Image: Aliseenko/ iStock

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Should you take a daily probiotic supplement?

There’s a lot of buzz around probiotics. They’re endorsed by celebrities and fill grocery stores aisles.

Probiotics are beneficial bacteria that promote a healthy gut. Scientists believe they could unlock a deeper understanding of our health. Probiotics are found in some foods and drinks, like yogurt or fermented tea.

Just like vitamins, probiotics are available as supplements. Manufacturers make steep claims about their benefits. They include digestive health, strengthened immune system, weight loss and reduced cancer risk. But can a supplement really do all that?

To learn more about probiotic supplements, we spoke with Carrie Daniel- MacDougall, Ph.D., M.P.H., a nutritional epidemiologist at MD Anderson who studies diet and the microbiome.

Here’s what you should know about probiotic supplements.

It’s always better to get nutrients from food. That includes probiotics.

“More research needs to be done on probiotics in general and probiotic supplements, but it’s always better to get your nutrients from food rather than supplements,” Daniel-MacDougall says. “They just don’t deliver the same benefits as food.”

One reason is because supplements aren’t regulated as closely as medications. So the quality and ingredients can vary greatly from product to product.

Unless your doctor is prescribing probiotics for a specific purpose, stick to getting them from foods like yogurt that may have other nutrients, like calcium.

Eat probiotic foods along with prebiotic foods. Prebiotics are the food that bacteria eats and what sustains good bacteria long-term. Oatmeal, bananas, berries, asparagus and beans are all prebiotics.

Chances are probiotic supplements won’t help you. There is also a chance they could hurt you.

Everyone’s microbiome – the collection of bacteria in their body – is different and exists in a delicate balance. So a probiotic supplement that helps one person might not help someone else.

“Maybe a probiotic supplement will have a positive effect on your digestive system if you’re lucky, but it’s likely it will have no effect,” Daniel-MacDougall says. “And it could even disrupt or displace some of the good bacteria you already have.”

This could result in an upset stomach or problems with digestion to feeling bloated as your microbiome is remodeling for better or forworse.

“I think the future of probiotics in medicine will be more personalized,” Daniel-MacDougall says.

There’s no quick fix.

“I think supplements are popular because we want a quick fix,” Daniel-MacDougall says. “We’re hoping that a pill can fix everything. Unfortunately, that’s not the case.”

Focus on eating healthy and getting exercise to feel your best. Aim for 150 minutes of moderate physical activity or 75 minutes of vigorous exercise each week to help lower your cancer risk.

Talk to your doctor before taking any supplement or making any major dietary changes.

In some cases, probiotics from food or supplements may help individuals with irritable bowel syndrome, Crohn’s disease or other health problems. But there is also potential for harm if used improperly or in combination with other medications. Your doctor can help you find the one that’s right for you.

How to choose a good probiotic supplement?

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