- Phytates and phytic acid. Here’s what you need to know.
- What is phytic acid?
- Who’s eating phytic acid?
- Phytate digestion
- Potential problems with phytic acid
- Potential benefits of phytic acid
- Phytic acid’s preventative properties
- In the balance
- Overcoming phytic acid as an antinutrient
- Bonus: Can other animals digest phytic acid?
- Summary and recommendations
- Passionate about nutrition and health?
- Interested? Add your name to the presale list. You’ll save up to 30% and secure your spot 24 hours before everyone else.
- Ask the Diet Doctor: Should I Soak Nuts, Seeds, and Grains?
- 4 Myths About Food and Nutrition
- MYTH: Raw Food is Better Than Cooked
- MYTH: Fresh Produce is Always Best
- MYTH: Eating Certain Foods Can Make Your Body Alkaline
- What is pH?
- MYTH: Phytic Acid Makes Grains and Legumes Poor Food Choices
- Absorption Friends and Foes
- Phytic Acid In Foods
- Phytic Acid and Paleo
- Summing it Up
- What is Phytic Acid?
- Possible Drawbacks
- 1) It is an Antioxidant
- 2) Reduces Inflammation
- 3) Induces Autophagy
- 4) Has Potential For Treating Multiple Cancers
- 5) Reduces Blood Glucose Levels
- 6) It is Neuroprotective
- 7) Reduces Triglycerides and Increases high-density lipoproteins (HDL)
- 8) Repairs DNA
- 9) Increases Bone Mineral Density
- 10) Protects Human Skin From UVB Exposure
- 11) Can Protect The Gut From Toxins
- 12) Helps Prevent Kidney Stones
- 13) Binds to Heavy Metals, Mycotoxins, Uranium, Iron, Manganese
- 14) Decreases Uric Acid/Helps Gout
- 15) It is Anti-HIV
- 16) Increases The Bioavailability of Flavones
- How Phytic Acid Interacts With Minerals
- In Conclusion
Phytates and phytic acid. Here’s what you need to know.
Phytic acid – the storage form of phosphorus – is one of those pesky “anti-nutrients” the Paleo community keeps telling you to avoid.
It’s often considered an anti-nutrient because it binds minerals in the digestive tract, making them less available to our bodies.
Yet these same anti-nutrient properties can also help in the prevention of chronic disease.
What is phytic acid?
Seeds — such as nuts, edible seeds, beans/legumes, and grains — store phosphorus as phytic acid. When phytic acid is bound to a mineral in the seed, it’s known as phytate.
The tables below compare various seed types according to their phytic acid/phytate content.
Source: Schlemmer U, et al. Phytate in foods and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysis. Mol Nutr Food res 2009;53:S330-S375.
Source: Schlemmer U, et al. Phytate in foods and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysis. Mol Nutr Food res 2009;53:S330-S375.
Source: Schlemmer U, et al. Phytate in foods and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysis. Mol Nutr Food res 2009;53:S330-S375.
Source: Schlemmer U, et al. Phytate in foods and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysis. Mol Nutr Food res 2009;53:S330-S375
As you can see, phytic acid content varies greatly among plants. This is due to the type of seed, environmental condition, climate, soil quality, how phytate is measured in the lab, and so forth.
Roots, tubers, and other vegetables may also contain phytic acid, but usually in lower amounts.
The most concentrated sources tend to be whole grains and beans. Phytic acid is isolated in the aleurone layer in most grains, making it more concentrated in the bran. In legumes, it’s found in the cotyledon layer (where the protein is).
Phytate = phytic acid bound to a mineral
Phytates perform an essential role in plants, as they are an energy source for the sprouting seed. When a seed sprouts, phytase enzymes break down the stored phytates.
When we eat the plant, phytates are hydrolyzed during digestion to myo-inositol-1,2,3,4,5,6-hexkisphosphate (IP6) and lower inositol polyphosphates including IP1 through IP5 (these are phytate degradation products).
Who’s eating phytic acid?
Everyone who eats plants consumes some phytic acid. It’s all a question of degree.
As you can imagine, intake tends to be much higher among those who follow non-Westernized diets. In developing countries, plants are staple foods, which means people eat more of them, and therefore get more phytic acid.
In developed countries, plant-based or vegetarian eaters tend to consume more phytic acid than omnivores. Further, males usually consume more phytic acid than females, simply because they eat more food.
Most phytate (37-66%) is degraded in the stomach and small intestines.
Ordinarily, our bodies regulate phytate levels pretty well, adjusting uptake in the gut and excretion until body levels come into balance.
Vitamin D status in the body seems to influence how much phytate is actually retained. The more vitamin D, the more phytate retained; the less vitamin D, the less phytate retained.
Potential problems with phytic acid
Phytic acid can bind minerals in the gut before they are absorbed and influence digestive enzymes. Phytates also reduce the digestibility of starches, proteins, and fats.
Here’s an example.
Vegan eaters often consume more iron than omnivores. Yet, they also consume more anti-nutrients, including phytates, and these reduce the amount of iron available to their bodies. Consuming 5-10 mg of phytic acid can reduce iron absorption by 50%.
This is why vegetarian eaters should eat more iron than omnivores (33 mg for veg eaters vs. 18 mg for omnivores).
Daily iron loss for men & women
- Adult men lose ~1 mg of iron per day
- Adult menstruating women lose ~1.4 mg/day
- Postmenopausal women lose ~0.8 mg/day
- Lactating women lose ~1.1 mg/day
While in the intestines, phytic acid can bind the minerals iron, zinc, and manganese. Once bound, they are then excreted in waste.
This can be a good or bad thing, depending on the condition. It’s a bad thing if you’re having trouble building up iron stores in the body and have developed iron-deficiency anemia.
When is it a good thing? Keep reading – you’ll find potential benefits of phytic acid below.
Potential benefits of phytic acid
Despite its potential drawbacks, phytic acid is similar in some ways to a vitamin, and metabolites of phytic acid may have secondary messenger roles in cells.
Some experts even suggest that it’s the phytic acid in whole grains and beans that lends them their apparent protective properties against cardiovascular disease, cancer, and diabetes.
(Remember, the grains with little to no phytic acid are the refined ones.)
The supplement industry has caught on to this. Have you even seen a bottle of inositol hexaphosphate, or IP6? That’s simply a supplemental source of phytic acid.
When phytic acid binds minerals in the gut, it prevents the formation of free radicals, thus making it an antioxidant. Not only that, but it seems to bind heavy metals (e.g., cadmium, lead) helping to prevent their accumulation in the body
Phytic acid’s preventative properties
Foods higher in phytic acid seem to enhance the activity of natural killer cells and inhibit tumor growth.
Those who consume more phytic acid are less likely to succumb to breast and prostate cancer. Exposing the colon to less iron seems to decrease the risk of colon cancer. And phytic acid might reduce the side effects of chemotherapy.
Source: Vucenik I & Shamsuddin AM. Protection against cancer by dietary IP6 and inositol. Nutrition and Cancer 2006;55:109-125.
Phytic acid helps prevent hardening of the arteries and platelet formation.
With some phytate being excreted in the urine, this may improve kidney health and prevent stones.
Phytic acid plays a role in pancreatic function and insulin secretion. And it may reduce the glycemic response from meals, meaning you feel full for longer.
Hemochromatosis, or iron overload, is a common genetic disorder that phytic acid’s iron-binding properties can protect against or reduce.
In the balance
Is phytic acid worth worrying about? Maybe not, for most of us.
One study showed that subjects consuming a Mediterranean-style diet that included 1000-2000 mg of phytic acid per day did not suffer from reduced mineral bioavailability.
At the same time, certain people might have to be more wary.
In particular, iron intake and absorption can be critical for infants nearing six months of age. So when plants are added to infants’ diets, it may be important to adopt strategies to reduce phytic acid and enhance iron absorption.
Overcoming phytic acid as an antinutrient
Luckily, it’s possible to overcome the anti-nutrient effects of phytic acid in our foods while still getting the benefits of a plant-rich diet. Here are a few strategies that my be more or less helpful depending on the specific situation:
Heating foods can destroy small amounts of phytic acid. (Note: heat can also destroy phytase and vitamin C.)
Milling grains and removing the bran decreases phytic acid. Unfortunately, milling also tends to remove many of the minerals! Removing the bran and then enriching a food with minerals might allow for enhanced nutrient absorption in the body.
Soaking beans and grains can reduce phytic acid (and other antinutrients).
Fermentation and bread leavening (using yeast) can help to break down phytic acid due to the activation of native phytase enzymes, reducing the number of phosphate groups.
This is big stuff since myo-inositol phosphates with fewer than five phosphate groups don’t inhibit zinc absorption (IP1 to IP4). And those with fewer than three phosphate groups don’t inhibit iron absorption (IP3 to IP2).
Also, some of the acids produced during fermentation might actually boost absorption of certain minerals.
Sprouting and malting enhances native phytase activity in plants and thus decreases phytic acid.
Vitamin C appears strong enough to overcome phytic acid. In one study, adding 50 mg of vitamin C counteracted the phytic acid load of a meal. In another study, 80 mg of ascorbic acid (vitamin C) counteracted 25 mg of phytic acid.
During processing of plant-based protein powders, it’s possible to de-phytinize (via addition of microbial phytase). Also, protein isolates and concentrates can be treated with dialysis or ultrafiltration to remove phytic acid.
Scientists are working on seed breeds containing less phytic acid. There are modern seed hybrids of grain and legume plants that contain less phytic acid.
Animal protein may enhance absorption of zinc, iron, and copper. Adding small amounts of animal protein might increase the absorption of these minerals in the body. (Well, except for dairy/casein, as it also seems to hinder iron and zinc absorption.)
A low pH in the gut enhances iron absorption. Balancing the level of beneficial bacteria in the GI tract might help with this. See All About Probiotics.
Sprouting enhances native phytase activity in plants and thus decreases phytic acid.
Bonus: Can other animals digest phytic acid?
Ruminant animals (e.g., cattle, sheep, goats, buffalo) possess phytase producing flora for digesting phytic acid.
Non-ruminant animals (e.g., pigs, chickens, dogs, cats) don’t have phytase producing flora, so phytic acid passes through them undigested and makes its way into the soil.
Feeding livestock too much grain can inhibit mineral absorption and increase phosphorus excretion, leading to pollution. Ever heard of the Dead Zone in the Gulf of Mexico?
Summary and recommendations
In healthy people eating balanced diets, phytic acid’s effects on iron, zinc, and manganese status is minimal and it doesn’t seem to cause nutrient deficiencies.
To argue that some plant foods are “unhealthy” because of their phytic acid content seems mistaken, especially when phytic acid’s potential negative effects on mineral assimilation may be offset by its health benefits.
So we should aim to reduce phytic acid rather than eliminate it.
To reduce the anti-nutrient effects of phytic acid in foods, try the following:
- Soak, sprout, ferment, and cook plant foods.
- Consume vitamin C-rich foods with meals that contain phytic acid. Dense source of vitamin C include guava, bell pepper, kiwi, oranges, grapefruit, strawberries, Brussels sprouts, cantaloupe, papaya, broccoli, sweet potato, pineapple, cauliflower, kale, lemon juice, and parsley.
- Use vinegar in salad dressings and cooking to enhance mineral absorption and offset phytic acid.
- Supplement with phytase enzymes if necessary.
- Eat mineral fortified foods if necessary
- Supplement minerals if there is still a shortfall in your diet.
- If you’re eating a plant-based diet and have confirmed nutrient deficiencies, and you’ve tried all the above strategies with no success, adding small amounts of animal foods on occasion might boost stores of necessary minerals in your body.
Consume vitamin C rich foods with meals that contain phytic acid to offset the effects.
Passionate about nutrition and health?
Learning how to coach clients, patients, friends, or family members through healthy eating and lifestyle changes (including how to accept indulgence) — in a way that supports long-term progress — is both an art and a science.
If you’d like to learn more about both, consider the Precision Nutrition Level 1 Certification. The next group kicks off shortly.
What’s it all about?
The Precision Nutrition Level 1 Certification is the world’s most respected nutrition education program. It gives you the knowledge, systems, and tools you need to really understand how food influences a person’s health and fitness. Plus the ability to turn that knowledge into a thriving coaching practice.
Developed over 15 years, and proven with over 100,000 clients and patients, the Level 1 curriculum stands alone as the authority on the science of nutrition and the art of coaching.
Whether you’re already mid-career, or just starting out, the Level 1 Certification is your springboard to a deeper understanding of nutrition, the authority to coach it, and the ability to turn what you know into results.
Interested? Add your name to the presale list. You’ll save up to 30% and secure your spot 24 hours before everyone else.
We’ll be opening up spots in our next Precision Nutrition Level 1 Certification on Wednesday, April 8th, 2020.
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If you’re ready for a deeper understanding of nutrition, the authority to coach it, and the ability to turn what you know into results… this is your chance to see what the world’s top professional nutrition coaching system can do for you.
Ask the Diet Doctor: Should I Soak Nuts, Seeds, and Grains?
Q: Do I need to soak nuts, seeds, and grains before eating them to remove anti-nutrients?
A: Soaking these foods in water for 12 is 24 hours is a common strategy to reduce their phytic acid content. Phytic acid is often pitched as a nutrition boogey man of sorts, preventing the absorption of key nutrients with growth-stunting consequences in third-world countries. What is interesting about phytic acid is that despite its “anti-nutrient” properties, the only thing it might be is a nutrition boogey man after all. Let’s explore…
Phytic acid is how certain grains “store” phosphorus and can make up as much as 7 percent of the dry weight of seeds and cereal grains. We can’t digest phytic acid because our bodies lack the necessary enzymes to break it down, and when it enters our digestive system, it can potentially cause problems.
The acid has the strongest affinity to multivalent metal ions (high school chemistry flashback alert!). In layman’s terms, that means it likes to bind to essential minerals such as calcium, zinc, iron, and magnesium, forming an insoluble compound that is poorly absorbed by your GI tract. Hence, deficiencies in these essential minerals could happen.
RELATED: 3 Snacks That Will Help You Lose Weight
However, nuts, seeds, and cereal grains are not the only sources of these nutrients, and most often they aren’t even a key contributor in your diet. The major sources of iron, calcium, magnesium, and zinc for most Americans are:
Iron: Red meat, seafood, nuts, dark green vegetables
Calcium: Dairy, dark green vegetables, beans
Magnesium: Spinach, nuts, and seeds (I recommend supplementing with extra magnesium anyway)
Zinc: Seafood (shellfish), meat, nuts
If you follow a diet that restricts some of the above food groups, such as a vegetarian or vegan diet, or you live in an area where getting in the bare minimum of essential nutrients is the major focus of your diet, then soaking your nuts, seeds, and cereal grains is probably warranted in order to free the essential minerals from the indigestible grips of phytic acid.
Otherwise, I’d skip the soaking. It is an unnecessary extra step and despite all the bad PR phytic acid gets, it has some potential health benefits. Research in animals shows that phytic acid can decrease risk factors for heart disease such as cholesterol and triglyceride levels. Its ability to bind with iron may be a benefit, as iron is a pro-oxidant and excessive levels can have negative effects on your health. Preliminary research also shows that it can stop growth of certain breast cancers.
- By Dr. Mike Roussell
What are nuts and seeds? A nut is a type of fruit. A fruit is a mature ovary from a flower. Every fruit contains one or more seeds. Every seed has the potential to germinate and grow into a mature adult plant. As seeds mature, the surrounding tissue develops into a fruit. This fruit can take many forms; some plants make berries (like blueberries or tomatoes), some make legumes (like peas and beans). The fruit of cereal grasses are grains like wheat or corn.
Many plants make a fruit called a nut. Technically, a nut is a single-seeded fruit with a hard, dry outer wall that doesn’t crack open at maturity, such as an acorn. Some things we call “nuts” are not, botanically speaking, nuts. A peanut is a legume. Almonds and coconuts are a type of fruit called a drupe.
OK! Now that we have had some science, forget all that and let’s talk about using nuts and seeds properly, and that means we have to get past the toxins in the seeds, make them more digestible, and get some answers on how many are really OK to eat. A handful? Three handfuls? A half-pound a day?
Seeds coat themselves with toxins as their defense system, designed to prevent ants, animals and humans from eating them. These toxins can be bitter, or poisonous, or damaging. We all learned in school that acorns were soaked before Indians ate them, but the same is still required for most other nuts and seeds today. All seeds should be well soaked and drained before eating. Whether you choose to then cook the wet seed (rice), or dehydrate it (hazelnuts or macadamias), or just use them wet on your salad or veggies (sunflower seeds, almonds), the first key step is to soak some of the toxins away.
Phytic acid is an anti-nutrient designed to keep the seed from sprouting prematurely. Unfortunately, it binds up minerals in our intestines, so we lose much of the valuable nutrients in nuts and beans that way. Soaking will remove much of this. Soaking will NOT remove the gluten and gluten-related toxins and lectins however. This is one reason why Ancestral Diets such as my Diet For Human Beings, and the Primal Blueprint diet suggest avoidance of all grains and beans.
Almond flour makes great muffins, quiche and pan cakes, but like whole almonds, it can contain phytic acid. Fortunately, buying blanched almond flour means the almonds have been skinned (removing much of the phytic acid and seed toxins) and then blanched, removing even more. Blanched almond flour is still very high in calories though, so a little goes a long way. A quarter cup of almond meal contains 15g fat, 5g carbs, 7g protein and 180 calories. And that’s basically just one big handful of almonds! Avoid almond meal, as it has the skins still on it and has not been blanched.
Nuts also contain varying amounts of Omega 6 polyunsaturated fats – the bad ones that we try to balance with Omega 3 fats. The nuts lowest in Omega 6 PUFA’s are macadamias, hazelnuts, almonds, cashews and chestnuts. These are your best nut choices. The nuts lowest in phytic acid are almonds, walnuts and chestnuts. Fortunately, soaking any of them will remove much of the phytic acid, so learn to do that properly (see Nourishing Traditions chapter on Snack Foods) or buy them that way at Wilderness Family Naturals, and others. Read here for more info on soaking.
If you have any of the RetroViruses such as Herpes, Epstein Barr, Cytomegalo Virus, or HIV, avoid nuts unless you take a Lysine capsule with them. These viruses feed on Arginine which is an amino acid that is high in nuts, grains and chocolate. Taking the Lysine will help, but don’t overdo…. This article on Best and Worst Foods for Herpes explains a lot more. I carry several great supplements for these viruses in my online store and clinic as well. See some here.
If your weight loss has plateaued on your Paleo Diet, check the amount of nuts and seeds (and nut butters) you’re eating. You may be using them as convenience foods rather than the condiment they really are.
4 Myths About Food and Nutrition
If you have a gastrointestinal (GI) disease or disorder, something as simple as eating can become complicated, which can cause nutritional deficiencies or questions about which foods are safe to consume. There are diseases such as Crohn’s and celiac that hinder the body’s ability to absorb certain nutrients adequately due to inflammation or other damage in the small intestine. In other GI ailments, symptoms such as nausea, vomiting, or fear of pain in the digestive tract can cause those affected to reduce the amount of food they consume or modify their diet in other ways, even by eliminating entire food groups, in their ongoing quest to quell symptoms. These behaviours can lead to inadequate nutrient intake, which is why we advise anyone living with a gastrointestinal disease or disorder to consult a registered dietitian, who can help ensure that you are still meeting your nutritional needs.
There is an abundance of nutritional advice listed across the internet, television, books, and magazines. However, most of these claims are unsubstantiated, yet many individuals turn to these quick resources to get advice on their nutritional needs, rather than see a dietitian. Even your best friend might try to convince you to eat certain foods. Who should you turn to? Who should you trust?
We’ve already mentioned in past articles that gluten often gets a bad rap, even though it causes no problems for those who don’t have celiac disease or a gluten sensitivity, which altogether comprise about 6-7% of the population.
In this article, we will review the facts and fabrications surrounding some common nutrition myths.
MYTH: Raw Food is Better Than Cooked
You may have heard that fresh fruits and vegetables are more healthful than cooked options because cooking destroys nutrients.
It’s true that the act of heating up food while cooking can destroy certain nutrients. Vitamin C is a fairly unstable compound, and exposing it to oxidation and high heat can damage it. The method of cooking can also make a difference. Certain vitamins are water soluble, which means they can seep into the water when boiling or steaming. In these cases, tossing the water means tossing the vitamins. However, if you boil veggies for a soup and keep the water for the broth, then you retain most of the benefits.4
On the other hand, some nutrients actually become more bioavailable when cooked.5 Cooking breaks down the fibrous walls of plant foods, which makes it easier for you to absorb certain nutrients that are closely bound to parts of the plant that are difficult to digest. If you cook tomatoes, the amount of bioavailable lycopene and phytonutrients increases.6 If you consume your tomatoes cooked, it takes fewer tomatoes for you to get the same amount of lycopene than it would if you ate them raw. Lycopene is an antioxidant that may help to prevent cancer, especially prostate cancer.7
CONCLUSION: Eating a variety of fresh and cooked foods is your best bet.
MYTH: Fresh Produce is Always Best
Biting into a ripe apple plucked straight from a tree is a delicious experience, but it is not one that’s easily replicated when buying produce from the grocery store. It makes intuitive sense to imagine that fresh fruits and veggies are healthier than their frozen counterparts; when you compare the food in its natural, brightly-coloured form to that in a plastic bag in the freezer aisle, it seems so obvious that fresh is better. However, the produce you purchase from an average grocery store, or even a high-end organic store, is often quite old. Before you bring it home, it goes through harvesting, processing, packaging, shipping, and then lands in your grocery store. Fresh produce can be days to weeks old, depending on the type of produce and where it was grown, and has lost some nutrients. It’s no longer quite the same as that tree-plucked apple. Since the produce has to make it through all that shipping without rotting, farmers sometimes pick the produce before it is ready, and then shortly before selling them, use ripening sprays made from calcium carbide or synthetic ethylene,1 which cause a reaction that mimics the natural ethylene ripening that produce typically undergoes.
Of course, if you are eating produce that you freshly picked from your garden, purchased directly from a local farmer, or produce that naturally lasts a long time (such as root vegetables), then this doesn’t apply.
Paradoxically, where frozen produce is concerned, suppliers typically harvest fruits and vegetables when they are perfectly ripe and freeze them immediately after harvesting them. This means that you end up with a product that is frozen in time with its nutrients intact and no need for ripening sprays. They also tend to be less pricey than fresh produce.
The process is similar for canned foods, and since cans last long and don’t need to be kept cool during transport, they can be an inexpensive addition to the diet.2 Just make sure to choose fruit soaked in water or juice rather than a thick syrup, and limit or rinse vegetables and beans with a high sodium content. While it is important to be aware of the potential of BPA, most cans in Canada have either no BPA or low enough levels that the Canadian Food Inspection Agency considers them safe.3
Fresh produce from the grocery store is still a great choice. However, you don’t need to shy away from frozen or canned fruits and vegetables if it suits your lifestyle or the dishes you are making. Frozen and canned vegetables go well in stir fries and soups, canned fruit makes a quick and easy snack, and you can add frozen fruit to smoothies, baked goods, and oatmeal. Whichever way you eat them, consuming a wide variety of fruits and vegetables is important.
CONCLUSION: Frozen and canned produce are inexpensive sources of nutritious fruits and vegetables.
MYTH: Eating Certain Foods Can Make Your Body Alkaline
Proponents of what is called the ‘alkaline diet’ or ‘alkaline ash diet’ claim that if you eat certain foods your body will become more alkaline, which supposedly leads to better health, while other foods can make your body more acidic, leading to illness. However, their definition for alkaline is not straightforward.
We use the pH scale to describe the acidity of various items. Vinegar has a pH of 3, which is very acidic, pure water has a pH of 7, which is neutral, and baking soda has a pH of 9, which is alkaline (also called basic). When people speak of the alkaline diet and alkaline foods, they aren’t referring to the pH of the foods themselves, but rather of the behaviour they exhibit in the body. When your body digests certain foods, the remains, called ‘ash’, are either acidic or alkaline, depending on the food. The idea is that this ash affects the pH of various parts of your body, causing beneficial or negative effects.
What is pH?
The term pH stands for ‘the potential of hydrogen’, which is a measure of the activity of hydrogen ions in a solution. We express this within a range where acidic is less than 7, neutral is 7, and alkaline is greater than 7, known as the pH scale.
Human blood is always a pH of 7.35-7.45.8 Blood that is more acidic indicates a severe disease state called acidosis that, if untreated, could lead to death. Blood that is more alkaline indicates alkalosis, which can also be dangerous. Other areas of the body have larger safe pH ranges, but they still need to remain in these ranges. For example, the skin typically has a pH between 4 and 7, but functions best when the pH is under 5 (which is acidic).9 Thankfully, our bodies do an amazing job of keeping our pH levels balanced, other than in extreme circumstances. As you can imagine, with such stringent specifications of healthful pH, it would be disastrous if the food we ate could easily affect our pH levels.
Your kidneys, liver, and lungs work to eliminate any compounds in your system that would affect pH. However, the pH of your urine can vary greatly depending on what you eat, since it is the process through which the body eliminates most of these waste products. Because of this, some people monitor their urine pH and use the results to judge the accuracy of the alkaline ash diet, even though the results of urine pH are not indicative of anything else in the body.10
Nevertheless, when it comes to your mouth, paying attention to pH is important. One good example is lemon juice, which is often touted as an alkalizing food. It doesn’t actually have an alkalizing effect on your body and the lemon itself is very acidic, with a pH of 2-2.5. This means that consuming large quantities of lemon juice for its supposed alkalizing benefits can actually be potentially damaging to your teeth due to its acidity.
Many of the foods that are considered alkaline (typically vegetables, fruits, legumes, etc.) are very nutritious foods that are beneficial to the body in many ways, but changing its pH isn’t one of them. This is why many people who start the alkaline diet might feel better, not because it is alkalizing their bodies, but because it encourages people to consume more nourishing foods and reduce the amount of processed food they consume. However, in the long run this diet might be lacking in certain nutrients, such as essential fatty acids.
CONCLUSION: You can’t change the pH of your body by eating certain foods.
MYTH: Phytic Acid Makes Grains and Legumes Poor Food Choices
You may have heard that some foods, such as wheat and beans, can actually prevent the absorption of certain nutrients. This is caused by a compound called phytic acid, which is found in most plants, but in especially high quantities in grains and legumes. Phytic acid prevents the absorption of minerals such as iron, calcium, manganese, and zinc by binding to them before your body can absorb them.11
Plants store phosphorus in a compound known as phytic acid. Phytic acid can bind to other minerals, such as those mentioned above, and in doing so creates phytates. Our bodies do not have any enzymes capable of breaking down phytates, so we are unable to absorb those nutrients.
However, by the time most of these foods get to our plate, they no longer contain enough phytates to cause problems. This is because sprouting, cooking, baking, processing, soaking, fermenting, and yeast leavening all help to destroy phytates. Since we typically don’t consume completely raw and unprocessed grains and legumes, by the time we consume these foods the amount of phytates remaining is considerably lower. In addition, there might even be health benefits to consuming phytic acid, which has anti-inflammatory and antioxidant effects.12
Most of these foods contain a wide array of nutrients, and many individuals consume them safely on a daily basis. The phytic acid does affect the total amount of minerals you absorb, but you still end up absorbing plenty. It only affects the meal that you consume them in, so eating a phytate-heavy lunch will have no influence on the amount of minerals you absorb from dinner. Avoiding these foods due to the fear that you aren’t absorbing the minerals can cause you to miss out on many nutrients. However, if you currently have mineral deficiencies (such as iron or zinc), you might want to limit your intake of phytic acid, or speak with a registered dietitian or your physician about any concerns.
CONCLUSION: Yes, phytic acid can bind to other minerals, but it doesn’t prevent you from absorbing all of the nutrients, and phytic acid itself might be beneficial.
Absorption Friends and Foes
There are some minerals that your body can have difficulty absorbing unless you combine them with other nutrients. If you want to boost your absorption of calcium, consume it with vitamin D.13 If you are trying to absorb more iron, combining it with vitamin C does the trick.14
The vitamins A, D, E, and K are what is known as fat soluble, which means you can’t adequately absorb them unless you consume dietary fat at the same time.15
On the flip side, some compounds make it more difficult for you to absorb nutrients. Tannins, which are a type of plant compound found in tea, coffee, and cocoa can strongly inhibit absorption of iron.16
Phytic acid is generally considered an “antinutrient,” and it’s one of the big reasons why Paleo excludes grains and legumes…but it’s more complicated than you might think. For example, did you know that it actually has some health benefits? Did you know that some Paleo foods actually have more phytic acid by weight than grains and legumes?
Once you carefully look at the evidence, this doesn’t actually change the Paleo recommendation to avoid grains and legumes – but it’s a perfect example of why nutrition isn’t black and white. Dividing foods or nutrients into “good” and “bad” categories with no middle ground is easy, but it’s not scientific, and it makes your nutritional choices hard to defend.
What Is Phytic Acid?
Phytic acid, or phytate, is a chemical compound found in all plant foods, mostly in the seeds of plant foods. Basically, it binds to minerals and helps store them for the seed to use as food later. The minerals most affected are iron, zinc, magnesium, and calcium. When the seed germinates, the sprout can use those minerals to grow.
That’s great for the plant, but unfortunately you are not a plant, and you can’t use minerals that have been bound to phytic acid. So even if a plant has a high amount of (say) calcium, if all that calcium is bound up with phytic acid, the calcium won’t actually be available to your body to break down and use (to build up your bones and teeth, restore minerals lost in sweat, regulate cardiac function, etc. etc.) So you’ll get less calcium from that food than the number on the Nutrition Facts panel suggests (You’d think this would be adjusted for in the nutritional information, but it’s not)
On top of reducing mineral absorption, phytic acid also reduces the production of digestive enzymes. This can make foods containing phytic acid harder to digest, especially for people who have trouble producing enough digestive enzymes in the first place.
So far, it’s looking pretty bleak. But take a look at the flip side.
Benefits of Phytic Acid
They exist! First, the rat studies:
- Because of the way it binds to calcium, phytic acid can help prevent the formation of kidney stones.
- Also because of its bonds to calcium, phytic acid might improve heart health by preventing calcium deposits in the arteries.
- In another study, a diet supplemented with phytic acid helped to prevent fatty liver by changing gene expression and modifying the gut bacteria.
- One last rat study: phytic acid improved gut health and reduced inflammation in rats fed a junk-food diet.
In humans, phytic acid in foods reduces the blood sugar spike in response to those foods. Phytic acid is also an antioxidant and in particular it helps prevent the oxidation of iron.
It’s not black and white. Phytic acid really represents a nutrient with both good and bad properties. The benefits come packaged together with the downsides. This study is the perfect example: a new strain of rice has a reasonable antioxidant content (from phytic acid), but at the cost of mineral bioavailability (because of phytic acid).
This isn’t a black-and-white problem – it’s a tricky question of finding a middle ground between extremes. The Paleo food template is an attempt to find that middle ground, but to understand how it works, it helps to take a look at how phytic acid comes packed in actual food.
Phytic Acid In Foods
Here’s a table showing the amount of phytic acid in different foods. (source is this study). The table gives the phytic acid in grams per 100 grams of the food, plus a rough estimation of how much “100 grams” of that food looks like in measurements that you actually use.
A few points to notice:
- There’s huge variation within each food. For example, wheat could have as little as 0.39 grams of phytic acid or as much as 1.35 grams per 100 grams of wheat (about 2/3 cup). The high value is over 3 times the amount of the low value! That’s like saying that the weight of an adult human is typically between 100 and 300 pounds – sure, it’s true, but it really makes a big difference where on that spectrum you fall.
- On average, nuts actually have much more phytic acid than either grains or legumes. Take a look at those high values. 9.42 grams for almonds? 6.69 for walnuts? Ouch! So if you’re wondering at this point why nuts are even considered Paleo, keep reading because that’s a question that really does need to be addressed.
Paleo includes nuts, but excludes grains and legumes. Now let’s take a look at why, and how that helps you get the benefits of phytic acid but without the downsides.
Phytic Acid and Paleo
Paleo is really the best of all possible worlds: it lets you avoid phytic acid with no negative consequences if you need to completely eliminate it, but also lets you consume a little bit if you’re OK with it, without jeopardizing your nutrient intake. Paleo eliminates staple foods high in phytic acid, but includes nuts as an optional “extra” or “pleasure” food that isn’t a
“Eat me…or also not. It’s cool either way.”
major source of any important nutrients. People who can’t handle any phytic acid can just avoid nuts without missing any nutrients, and people who can handle phytic acid can get it occasionally from nuts without jeopardizing their primary source of nutrition. It’s basically a flexible template that lets you choose your own level of phytic acid exposure.
Almost all the studies showing the dangers of phytic acid in humans were done on people eating staple foods rich in phytic acid. People who eat the bulk of their calories from grains and don’t get a lot of animal foods have nutrient deficiency problems from phytic acid. This is quite common in the developing world, but not so much in the US. By Paleo standards, foods high in phytic acid shouldn’t be staple foods, because they cause obvious problems for human health that totally outweigh any potential antioxidant benefits they might have.
If you were only judging by phytic acid without considering any other factors, grains might be OK on Paleo in small doses. But of course, there are lots of other factors that take grains off the plate. On the other hand, for nuts, there isn’t any decisive factor that would argue for eliminating them completely. (Unless you have a nut allergy, but that’s a personal issue and doesn’t apply to people without allergies). Even the Omega-6 fats aren’t dangerous in small doses.
On Paleo, nuts aren’t a staple food, and you’re not relying on them as a source of iron, calcium, or any other nutrients. So the phytic acid they contain isn’t jeopardizing your nutrition. On the other hand, Paleo also has plenty of other antioxidants and plenty of other foods that are good for blood sugar control, so if you can’t handle phytic acid, it’s not a crisis:
- If you have weak digestion, skip them: you don’t need another food suppressing your production of digestive enzymes. Nuts are notoriously hard to digest, and phytic acid might be one reason why.
- If you have serious mineral deficiencies, skip them.
- If you don’t have any digestive problems with nuts, and you don’t have anemia or any other mineral deficiencies, nuts in small doses are fine. You can get the antioxidant and other benefits of phytic acid, without jeopardizing and important source of nutrients in your diet, because you were never relying on nuts for iron or calcium anyway. You have steak and green vegetables for that!
As a side note, if you do have to compromise on Paleo (no judgement! Life isn’t always smooth sailing!), there are ways to minimize phytic acid even in grains and legumes. Soak them before cooking, and cook them for as long as you can – it’s not ideal, but it’s better than nothing.
Summing it Up
Phytic acid isn’t a nutrient that you can shove in a box and classify as “good” or “bad.” It has some good properties, and it has some bad properties.
Staple foods rich in phytic acid, like grains and legumes, probably aren’t right for most people. And grains and legumes have problems besides phytic acid anyway. But in the Paleo template, nuts give you the chance to either remove phytic acid completely (if you need to) or leave a little bit of it in, in a way that doesn’t jeopardize your major nutrient sources. It’s a flexible template that leaves room for individual people to do what works best for them – there’s no one-size-fits-all in nutrition.
Phytic acid, often regarded as harmful, is misunderstood in the health community. It has many surprising health benefits that make it more healthy than not. Read on to discover 16 ways phytate can work for you.
What is Phytic Acid?
Phytic acid aka phytate is found in whole grains, legumes, potatoes, nuts, and seeds. It is demonized in the paleo movement as an anti-nutrient, from which we should stay away.
The reason it’s referred to as such is that it binds minerals such as calcium, iron, potassium, magnesium, manganese, zinc, copper, and selenium, therefore, supposedly making them insoluble and thus unavailable for absorption in the intestinal tract of humans.
The picture isn’t so clear, however, and phytate also has a number of health benefits. This post is meant to demonstrate the phytic acid isn’t the villain it’s portrayed to be and is instead on the whole more healthful than not.
I don’t advocate supplementing with phytic acid since there’s an abundant supply of starches and plant foods (on a lectin avoidance diet, phytate is mostly removed).
Phytate is capable of being absorbed in our GI tract .
Phytate levels in serum peak 4 hours after ingestion .
Note that phytic acid, phytate, PA, inositol hexaphosphate and IP6 all refer to the same compound.
Before I speak about the benefits, I’d like to mention some drawbacks.
Phytate has been shown to inhibit digestive enzymes such as trypsin, pepsin, α-amylase, and ß-glucosidase . Alpha-amylase inhibition is used by diabetics to slow glucose absorption, so that’s actually not bad.
Phytic acid in excess is said to cause some GI issues, but I haven’t found scientific evidence of this. There were no harmful GI effects in mice fed significant quantities of phytate . I believe that the GI irritation from foods with phytate is actually coming from dietary lectins.
When I took phytase to break down phytic acid I didn’t notice a difference with regard to inflammation from food. However, when I took sugars that bind to lectins I did notice a significant difference. This is one way I realized that phytic acid wasn’t the main culprit for me, but rather lectins were. I’ve also consumed phytate supplements, without any ill effects.
Phytate can bind to certain minerals, which I discuss below, but for the most part, it’s not an issue. The main mineral that you should be concerned with is Zinc, which is why you should supplement with it if you have a plant-based diet.
1) It is an Antioxidant
Phytic acid has protected against alcohol-related liver injury by blocking free radicals and elevating antioxidant potentials .
The anti-oxidative action of phytic acid is as a result of inhibiting Xanthine Oxidase and by ‘preventing a formation of ADP-iron-oxygen complexes’ . It was also able to protect DNA from free radicals .
Roasting/cooking foods with phytic acid improved antioxidant ability .
2) Reduces Inflammation
Phytic acid was found to decrease the inflammatory cytokines IL-8 and IL-6, especially in colon cells .
3) Induces Autophagy
Phytic Acid was found to induce autophagy .
Autophagy is a cellular process for degrading and recycling junk proteins .
It has recently been recognized as a principal response to cellular stress and an important regulator of neuronal function and survival .
It plays a role in the destruction of pathogens inside our cells .
As a ‘quality control’ process, autophagy is believed to be particularly beneficial in neurodegenerative disorders – Alzheimer’s, Parkinson’s, ALS and Huntington’s. This is because these disorders are, in part, characterized by the accumulation of misfolded disease-causing proteins .
Research suggests that autophagy is required for the lifespan-prolonging effects of caloric restriction and for much of the health benefits of exercise . Inhibiting mTOR increases autophagy, which is part of the reason mTOR inhibition increases longevity .
4) Has Potential For Treating Multiple Cancers
Mechanism: suppressing the expression of matrix metalloproteinases (MMPs) and telomerase .
5) Reduces Blood Glucose Levels
Studies show that phytate reduces blood glucose levels in mice and rats .
It works in part by slowing the rate of starch digestibility .
6) It is Neuroprotective
Neuroprotective effects of Phytic acid were found in a cell culture model of Parkinson’s disease .
It was found to protect against 6-Hydroxydopamine-Induced dopaminergic neuron apoptosis, which causes Parkinson’s .
By inducing autophagy, it can also protect against Alzheimer’s and other neurodegenerative diseases.
7) Reduces Triglycerides and Increases high-density lipoproteins (HDL)
Studies have found phytate reduces triglycerides and increases HDL cholesterol (the good one) in rats .
8) Repairs DNA
It was found that phytic acid can enter cells and help DNA repairs breaks in the strands. This is a potential mechanism by which phytate prevents cancer .
9) Increases Bone Mineral Density
Phytate consumption had a protective effect against osteoporosis. Low phytate consumption is a risk factor for osteoporosis .
Adequate consumption of phytate may play an important role in the prevention of bone mineral density loss in postmenopausal women .
10) Protects Human Skin From UVB Exposure
UVB radiation damages skin cells, which can cause skin damage, cancer and suppression of the immune system .
Studies show that phytic acid protects cells from UVB-induced destruction and mice from UVB-induced tumors .
11) Can Protect The Gut From Toxins
Phytic acid supplementation increased gut transit time and resulted in more efficient absorption of nutrients (via ‘surface amplification’) .
Phytate also protects intestinal cells from certain toxins – at least in pigs .
12) Helps Prevent Kidney Stones
In rats treated with phytic acid, calcifications in their kidneys were reduced, which suggests a potential for preventing kidney stones .
Another animal study found that it inhibited the formation of calcium oxalate stones .
In a study on humans, phytate urinary levels in a group of active calcium oxalate stone formers were studied and compared with those found in healthy people. Urinary phytate was significantly lower for stone formers .
Low phytate levels may be why kidney stones are more of a problem in the paleo world.
13) Binds to Heavy Metals, Mycotoxins, Uranium, Iron, Manganese
Phytic acid is one of a few chelating therapies used for uranium removal .
Phytic Acid reduces the toxicity of mycotoxins, which may be explained by its antioxidant activity .
It also binds to heavy metals, iron, and manganese. Iron and manganese are nutrients that we normally get too much of, but not always. If we do have an excess, then that can have ill effects on our health.
14) Decreases Uric Acid/Helps Gout
By inhibiting the enzyme xanthine oxidase, phytic acid blocks the buildup of uric acid and can help prevent gout .
15) It is Anti-HIV
Phytate was able to inhibit the replication of HIV-1 in cell lines. PA was only beneficial on an early replicative stage of HIV-1-infection .
16) Increases The Bioavailability of Flavones
Phytate is a potential absorption enhancer for pharmaceuticals/supplements.
The oral bioavailability of isorhamnetin, kaempferol, and quercetin was enhanced by the co-administration of phytate.
The main mechanisms are related to their enhanced aqueous solubility and permeability in the presence of phytate .
How Phytic Acid Interacts With Minerals
There’s really only a few minerals that phytate binds to and as a result of the binding may potentially lead to health problems.
The minerals you should pay attention to are Zinc, and to a lesser extent, calcium and chromium.
Phytic acid can bind to zinc somewhat strongly and can cause GI problems, among other health issues. Zinc binding I think is the biggest issue and most people eating a plant-based diet should supplement with a small amount of zinc. Not only is phytate a problem because of zinc binding, but since eating such a diet contains a lot of copper, it will interfere further with zinc absorption. For these reasons, I supplement with 15mg of zinc glycinate and recommend this dosage to others, especially men. Women need less zinc, so it’s less likely to as big of a problem for them (RDA for men 19+ yrs old is 11mg and 8mg for women). 10mg of supplemental zinc should suffice for women.
Phytate can also bind to calcium, albeit not as strong as it binds to zinc. But not only have I not seen health problems as a result of this binding to calcium, I’ve only seen studies where it increases bone mineral density, which is unexpected. We obviously don’t have the full story. My wild guess is that it mainly binds to extra calcium that the body isn’t using and helps utilize or retain the rest of the calcium in some fashion. I supplement with 250mg 2X a day, not so much because of the phytic acid, but more because I don’t eat dairy and I don’t get the recommended level of calcium. If I did eat dairy, I’d consume maybe 150mg of calcium just to be safe (the RDA is 1000mg), because after all, phytic acid does bind to calcium. Linus Pauling Institute: “Phytic acid is a less potent inhibitor of calcium absorption than oxalate. Only concentrated sources of phytate, such as wheat bran or dried beans, substantially reduce calcium absorption.” So, I think people should focus on getting the RDA for calcium and maybe take a bit more if you consume a lot of phytates – just in case.
Binding of phytic acid to magnesium is not a good thing, but the foods with phytic acid are also usually rich in magnesium.
I’ve also seen a study where it binds to chromium and I was deficient in chromium at one point, so that may be a problem, too. Chromium deficiency is supposedly rare, but my experience possibly suggests otherwise, since I was eating a whole food diet with no added sugar (sugar causes excretion of chromium). It could be that I was deficient in chromium not because of phytic acid but because of decreased gut function from ingesting gluten or from a zinc deficiency. I take 100mcg of chromium GTF every day. These interventions are extremely cheap, simple and safe, so I find the drawbacks of consuming phytic acid to be very minimal.
Most people actually have too much iron. I’ve experimented with a starch-based diet for a while and my iron levels were still higher than the ideal range for anti-aging purposes, and that was without eating red meat. In addition, I also drank tea, kombucha, curcumin and a bunch of other iron chelators. Iron is in all foods and deficiency is usually caused by something else other than low consumption of iron. This is the reason you see some people donating blood to get rid of excess iron.
Menstruating women should monitor their iron levels more closely, however. I should also mention that people have different genetics with regard to how well they retain iron and I might be – genetically – a good iron storer.
Selenium is an important mineral that I supplement with since it’s good for autoimmune conditions of the thyroid. I take 100mcg daily, which is a conservative dosage. I also make sure not to eat brazil nuts or else I may be getting too much of it. Phytate doesn’t seem to be an issue for selenium, at least according to this study on baby chicks. If anything it seems to be a benefit. A quote:
“Phytate increased selenium in all tissues except muscle; it is not clear if this resulted from increased absorption or increased retention.”
The fact the phytate binds to manganese is a plus since people get too much manganese in a starch-based diet.
Copper absorption is actually enhanced by phytic acid in copper-deficient diets. I don’t know what would happen in diets that weren’t deficient in copper. I’d actually rather it bind to copper because starch-based diets are too high in copper. In any case, zinc supplementation should reduce copper absorption, so no worries here.
If you adopt a plant-based omnivorous diet you likely won’t have a problem, except for zinc. If you want to be safe you can take a small amount of chromium and calcium, though there’s no evidence that it’s necessary if you consume dairy and a balanced diet. This is a very small price to pay to get the health benefits of phytate. A review article on phytate and minerals in a vegetarian diet (not a diet I support):
Despite the apparent lower bioavailability of zinc, copper, manganese, and selenium in vegetarian diets because of the high contents of phytic acid and/or dietary fiber and the low content of flesh foods in the diet, the trace element status of most adult vegetarians appears to be adequate. Children, however, appear to be more vulnerable to suboptimal zinc status, presumably because of their high zinc requirements for growth and their bodies’ failure to adapt to a vegetarian diet by increased absorption of dietary zinc .
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