Phytic acid is found in seeds, nuts, beans, grains, seeds and other plant matter. It is also found in grains and nuts like almonds, pumpkin seeds, soybeans, lentils, and other seeds. Phytic acid is thought to be responsible for the health benefits of eating grains and nuts. However, phytic acid has the effect of reducing the absorption of minerals like iron, calcium and zinc when consumed in the diet.

Phytic acid in foods may be the single most important factor in the phytates that are present in our diets. Phytic acid is a mineral found in plant seeds, grains, and nuts which helps keep our bodies healthy. But phytates are also found in our daily diets. This phytate-containing compound is found in, among other foods, beans, legumes, whole grains, and seeds.

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.

Whole grains

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.

Legumes

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.

Nuts

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.

Oil seeds

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).

Over 150,000 health & fitness professionals certified

Save up to 30% on the industry’s top nutrition education program

Get a deeper understanding of nutrition, the authority to coach it, and the ability to turn that knowledge into a thriving coaching practice.

Learn More

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.

Phytate digestion

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

Cancer

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.

Cardiovascular disease

Phytic acid helps prevent hardening of the arteries and platelet formation.

Kidney stones

With some phytate being excreted in the urine, this may improve kidney health and prevent stones.

Insulin resistance

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

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:

Heat

Heating foods can destroy small amounts of phytic acid. (Note: heat can also destroy phytase and vitamin C.)

Processing

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

Soaking beans and grains can reduce phytic acid (and other antinutrients).

Fermenting

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

Sprouting and malting enhances native phytase activity in plants and thus decreases phytic acid.

Vitamin C

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.

Protein powders

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.

Seed breeding

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

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.)

Gut health

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.

 

References

Click here to view the information sources referenced in this article.

Hunt JR & Roughead ZK. Nonheme-iron absorption, fecal ferritin excretion, and blood indexes of iron status in women consuming controlled lactoovovegetarian diets for 8 wk. Am J Clin Nutr 1999;69:944-952.

Siegenberg D, et al. Ascorbic acid prevents the dose dependent inhibitory effects of polyphenols and phytates on nonheme-iron absorption. Am J Clin Nutr 1991;53:537-541.

Norris J. Vegan Health. http://www.veganhealth.org/articles/iron

Seshadri S, Shah A, Bhade S. Haematologic response of anaemic preschool children to ascorbic acid supplementation. Hum Nutr Appl Nutr 1985;39:151-154.

Sharma DC & Mathur R. Correction of anemia and iron deficiency in vegetarians by administration of ascorbic acid. Indian J Physiol Pharmacol 1995;39403-406.

Linus Pauling Institute. Iron. http://lpi.oregonstate.edu/infocenter/minerals/iron/

Raboy V. Progress in breeding low phytate crops. J Nutr 2002;132:503S505S.

Hotz C & Gibson RS. Traditional food-processing and preparation practices to enhance the bioavailability of micronutrients in plant-based diets. J Nutr 2007;137:1097-1100.

Davidsson L. Approaches to improve iron bioavailability from complementary foods. J Nutr 2003;133:1560S-1562S.

Singh RP & Agarwal R. Prostate cancer and inositol hexaphosphate: efficacy and mechanisms. Anticancer Research 2005;25:2891-2904.

Vucenik I & Shamsuddin AM. Cancer inhibition by inositol hexaphosphate (IP6) and inositol: from laboratory to clinic. J Nutr 2003;133:3778S-3784S.

Examine.com Inositol Hexaphosphate. December 11, 2012. http://examine.com/supplements/Inositol+Hexaphosphate/

Memorial Sloan-Kettering Cancer Center. Inositol Hexaphosphate. January 18th, 2013. http://www.mskcc.org/cancer-care/herb/inositol-hexaphosphate

Hurrell RF. Influence of vegetable protein sources on trace element and mineral bioavailability. J Nutr 2003;133:2973S-2977S.

Lonnerdal B. Dietary factors influencing zinc absorption. J Nutr 2000;130:1378S-1383S.

Sandberg A. Bioavailability of minerals in legumes. British Journal of Nutrition 2002;88(Suppl 3):S281-S285.

Murgia I, et al. Biofortification for combating ‘hidden hunger’ for iron. Trends in plant science 2012;17:47-55.

Itske M, et al. Effect of tea and other dietary factors on iron absorption. Critical Reviews in Food Science and Nutrition 2000;40:371-398.

Gilani GS, Xiao CW, Cockell KA. Impact of antinutritional factors in food proteins on the digestibility of protein and the bioavailability of amino acids and on protein quality. British Journal of Nutrition 2012;108:S315-S332.

Hurrell R & Egli I. Iron bioavailability and dietary reference values. Am J Clin Nutr 2010;91:1461S-1467S.

Gibson RS, Perlas L, Hotz C. Improving the bioavailability of nutrients in plant foods at the household level. Proceedings of the Nutrition Society 2006;65:160-168.

Hunt JR. Moving toward a plant-based diet: are iron and zinc at risk? Nutr Rev 2002;60:127-134.

Fardet A. New hypotheses for the health-protective mechanisms of whole-grain cereals: what is beyond fibre? Nutrition Research Reviews 2010;23:65-134.

Champ MMJ. Non-nutrient bioactive substances of pulses. British Journal of Nutrition 2002;88 Suppl 3:S307-S319.

Vohra A & Satyanarayana T. Phytases: Microbial sources, production, purification, and potential biotechnological applications. Critical Reviews in Biotechnology 2003;23:29-60.

Bohn L, Meyer AS, Rasmussen SK. Phytate: impact on environment and human nutrition. A challenge for molecular breeding. Journal of Zhejiang University SCIENCE B 2008;9:165-191.

Ma G, et al. Phytate intake and molar ratios of phytate to zinc, iron and calcium in the diets of people in China. European Journal of Clinical Nutrition 2007;61:368-374.

Raboy V. Seeds for a better future: ‘low phytate’ grains help to overcome malnutrition and reduce pollution. TRENDS in Plant Science 2001;6:458-462.

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.

Vucenik I & Shamsuddin AM. Protection against cancer by dietary IP6 and inositol. Nutrition and Cancer 2006;55:109-125.

Fox CH & Eberl M. Phytic acid (IP6), novel broad spectrum anti-neoplastic agent: a systematic review. Complementary Therapies in Medicine 2002;10:229-234.

Gibson RS, et al. A review of phytate, iron, zinc, and calcium concentrations in plant-based complementary foods used in low-income countries and implications for bioavailability. Food Nutr Bull 2010;31(2 Suppl):S134-S146.

Urbano G, et al. The role of phytic acid in legumes: antinutrient or beneficial function? J Physiol Biochem 2000;56:283-294.

If you’re a coach, or you want to be…

Learning how to coach clients, patients, friends, or family members through healthy eating and lifestyle changes—in a way that’s personalized for their unique body, preferences, and circumstances—is both an art and a science.

If you’d like to learn more about both, consider the Level 1 Certification.

Frequently Asked Questions

Should I worry about phytic acid?

Phytic acid is a naturally occurring substance found in whole grains, nuts, and seeds. It can bind to minerals like calcium, magnesium, iron and zinc in the digestive tract and prevent their absorption. Phytic acid is also known to inhibit the enzyme that helps your body break down carbohydrates into glucose. The phytates in whole grains are not an issue for most people because they are broken down by enzymes during cooking or soaking. If you have a condition that prevents your body from breaking down phytates, you may want to avoid whole grains. Should I worry about gluten? Gluten is a protein found in wheat, barley and rye. It can cause digestive issues for some people and is often the cause of celiac disease. If you have celiac disease or are gluten sensitive, it’s best to avoid all forms of wheat, barley and rye. If you don’t have celiac disease or are gluten sensitive, you can enjoy a small amount of gluten-containing grains like quinoa and amaranth.

What does phytic acid do to the body?

Phytic acid binds to minerals in the body, making them unavailable for absorption.

What foods are high in phytates?

Phytates are found in whole grains, nuts, seeds, and legumes.

symptoms of too much phytic acidphytic acid mythhow to remove phytic acid from nutsphytates and ironphytic acid free dietphytic acid teeth,People also search for,Feedback,Privacy settings,How Search works,symptoms of too much phytic acid,phytic acid myth,how to remove phytic acid from nuts,phytates and iron,phytic acid free diet,phytic acid teeth,phytates benefits,phytic acid in rice

You May Also Like

What to do when you don’t like vegetables. 3 steps for training your palate (and why it’s important).

One of the most important aspects of a healthy diet is to…

All About Protein Powders |

Protein powders are made up of a variety of ingredients, and what’s…

The beginner bodyweight workout plan

The world of Fitness is full of people spouting the latest fitness…

Nutrition for Injury Recovery

After a long day at the office, a workout can help you…