Vitamins, Minerals and Dietary Supplements
What is phytic acid? Why do we need it?
Phytic acid is a naturally forming component found in plant fiber. It is known by several other names, including phytate, inositol hexaphosphate, and IP-6. While relatively little human research with phytic acid has been conducted, it is believed to possess some of the properties of well-known antioxidants, in addition to other as-yet-unknown benefits.
Many animal studies have shown that phytic acid can protect against some types of cancer, including cancers of the breast and colon. Injections of phytic acid have also demonstrated the ability to reduce the size of cancerous tumors in mice. Phytic acid may also have a beneficial effect on controlling blood sugar, and may reduce the incidence of kidney stones. As of this writing, however, virtually all research on phytic acid has involved the use of animals. As a result, it is not known how well humans can absorb or utilize phytic acid, if at all.
How much phytic acid should I take?
Because most of the research on phytic acid has been conducted on animals, scientists have been unable to determine an optimal amount of phytic acid intake. The typical diet provides between 1 and 1.5 grams of phytic acid per day, much of it derived from grains and legumes.
What forms of phytic acid are available?
Phytic acid is available in a wide range of plant foods, including wheat bran, whole grain, and legumes. Nuts and seeds also contain phytic acid, but in smaller amounts compared to bran and grains.
What can happen if I take too much phytic acid? Are there any interactions I should be aware of? What precautions should I take?
In animal studies, phytic acid intake has been associated with reduced absorption of certain minerals, especially iron. As a result, people who are anemic or iron deficient should talk with a health care provider about increasing iron supplementation before taking phytic acid supplements.
As of this writing, there are no known drug interactions with phytic acid. As always, make sure to consult with a licensed health care provider before taking phytic acid or any other dietary supplement or herbal remedy.
- Graf E, Eaton JW. Antioxidant functions of phytic acid. Free Radic Biol Med 1990;8:61-9.
- Harland BF, Morris ER. Phytate: a good or a bad food component? Nutr Res 1995;15:733-54.
- Sandberg A-S, Brune M, Carlsson N-G, et al. Inositol phosphates with different numbers of phosphate groups influence iron absorption in humans. Am J Clin Nutr 1999;70:240-6.
- Vucenik I, Sakamoto K, Bansal M, et al. Inhibition of rat mammary carcinogenesis by inositol hexaphosphate (phytic acid). A pilot study. Cancer Lett 1993;75:95-102.
- Vucenik I, Yang G, Shamsuddin AM. Comparison of pure inositol hexaphosphate and high-bran diet in the prevention of DMBA-induced rat mammary carcinogenesis. Nutr Cancer 1997;28:7-13.