Phytic acid: Simple kitchen techniques to reduce it in food

Phytic acid is a substance found primarily in grains, legumes, nuts, and seeds that inhibits your absorption of minerals. People who rely on these foods for iron, magnesium, calcium, or zinc can improve their mineral status by using these simple kitchen techniques.

The most effective technique for all of these foods is fermentation. Sourdough bread is a great example of a fermented grain. Soaking helps as well: beans can be soaked overnight to reduce phytic acid. Below are some quick techniques to reduce phytic acid in food.

"Soaking" grains is an increasingly popular method of reducing phytic acid made popular by Sally Fallon in her book Nourishing Traditions. She argues that all grains should be soaked overnight in an acidic medium. The video below offers a good tutorial on the process.

Soaking, however, does not work with all grains (see the oatmeal article below as an example). Fermentation (e.g. sourdough or fermented porridge) is a better option.

If you master fermentation techniques, you need not worry about phytic acid. Any food can be fermented. If you are cooking and baking anyway, fermentation is a fairly easy next step.

Sourdough bread recipes abound. Creative bloggers have given us solutions even for sourdough crackers. (Search that blog for fermented rice as well.)

Beans contain high levels of phytic acid and they are an important food in the vegetarian diet. Soaking beans reduces phytic acid and actually improves the general digestibility of beans (and thus reduces the gas factor).

Any bean you cook, be it chickpeas for hummus, pinto beans for chili, or black beans for soup, you will benefit from soaking them.

Phytic acid research shows us that increased soak time and water temperature improves the reduction of phytic acid. This article on phytic acid in beans displays the food science findings in some detail. I typically soak add hot (but not boiling) water to my beans and let them soak overnight (and preferably for 18 hours). It's ideal as well to keep your beans in a warm spot during that soak time, but the overnight or 18-hour soak is powerful nonetheless.

While black beans, chickpeas, great northern beans, pinto beans, and other common beans in our kitchen can be soaked to reduce phytic acid, soy beans are a phytic acid exception.

Note in the graph at right that soybeans can be soaked and steamed but the real phytic acid reduction happens at the point of fermentation. Fermented foods such as tempeh and miso will be good sources of minerals. Soy milk is a product of cooked soybeans and will contain the lion's share of the original phytate content.

It may actually be a good thing that phytic acid inhibits the absorption of minerals in your high-phytate food. People with high levels of iron, for instance, can eat a vegetarian diet without using these techniques and feel fairly secure that their diet is not causing iron overload. (Blood testing is the best way to monitoring iron status.)

Whether you should be concerned about phytic acid in your food or whether you should embrace it really does depend on your own nutritional status. Watch the phytic acid video below for a short rationale.