Paleo Diet Myth

Should You Fear Phytic Acid?

Sometimes demonized as an evil “anti-nutrient,” phytic acid can prevent you from absorbing essential minerals. But it also has lots of disease-fighting properties. Plus it’s found in healthy plant-based foods like legumes and whole-grains. Find out how to minimize phytic acid in your food, without giving up on the good stuff.

If you’ve ever heard of phytic acid or phytates it’s probably because someone told you that you should avoid them.

Phytic acid is sometimes considered an “anti-nutrient” because it binds minerals in the digestive tract, making them less available to our bodies.

The most concentrated sources of phytic acid are usually whole grains and beans. And that's why some people (especially folks on the Paleo diet) are afraid of eating these foods for their supposed “anti-nutrient” properties.

But these same anti-nutrient properties can also help in the prevention of chronic disease.

Potential problems with phytic acid

Phytic acid can bind minerals in the gut before they are absorbed and interact with digestive enzymes. Phytates also reduce the digestibility of starches, proteins, and fats.

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.

On the other hand, 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

In fact, phytic acid has some great preventative properties. For example: it helps fight cancer, cardiovascular disease, kidney stones, and insulin resistance.

For most people, the fact that they contain phytates probably isn’t a good enough reason to stop eating legumes or whole grains.

That said, there are some steps you can take to reduce the anti-nutrient effects. (This might be especially important if you’re a plant-based eater, with a vegetarian or vegan diet.)

Here are some of the best ways to moderate the anti-nutrient effects:

- Heat your food. Heating foods can destroy small amounts of phytic acid. (Note: heat can also destroy phytase and vitamin C so be careful.) 

- Soaking beans and grains can also reduce phytic acid (and other anti-nutrients).

- Eat fermented foods. 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. Also, some of the acids produced during fermentation might actually boost absorption of certain minerals.

- Eat sprouted grains. Sprouting and malting enhances native phytase activity in plants and thus decreases phytic acid.

- Add 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. 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.

- Eat 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.   (Except for dairy/casein, as it also seems to hinder iron and zinc absorption.)

- Support your 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.   

In the end, 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.

On balance, you don’t need to stop eating whole grains, legumes, or God forbid, fruits and vegetables. Just aim to reduce phytic acid through preparation methods rather than eliminating the foods that contain it.