(NaturalNews) Phytic acid in grains, nuts, seeds and beans represents a serious problem in our diets. This problem exists because we have lost touch with our ancestral heritage of food preparation. Instead our culture, be it the U.S. Department of Agriculture (USDA) or the health food crowd, generally promotes consumption of high-phytate foods like commercial whole wheat bread and all-bran breakfast cereals. But phytate rich foods are not healthy for us.
Phytic acid is the principal storage form of phosphorus in many plant tissues, especially the bran portion of grains and other seeds. It contains the mineral phosphorus tightly bound in a snowflake-like molecule. In humans and animals with one stomach, the phosphorus is not readily bioavailable. In addition to blocking phosphorus availability, the "arms" of the phytic acid molecule readily bind with other minerals, such as calcium, magnesium, iron and zinc, making them unavailable as well. In this form, the compound is referred to as phytate. Phytic acid not only grabs on to or chelates important minerals, but also inhibits enzymes that we need to digest our food: including pepsin, (Footnote 1) needed for the breakdown of proteins in the stomach, and amylase, (F 2) needed for the breakdown of starch into sugar. Trypsin, needed for protein digestion in the small intestine, is also inhibited by phytates. (F 3)
A diet high in phytate-rich grains has many powerful anti-nutritional effects. Many health problems can result: including tooth decay, nutrient deficiencies, lack of appetite and digestive problems.
The presence of phytic acid in so many enjoyable foods we regularly consume makes it imperative that we know how to prepare these foods to neutralize phytic acid content as much as possible, and also to consume them in the context of a diet containing factors that mitigate the harmful effects of phytic acid.
Phytic acid is present in beans, seeds, nuts, grains - especially in the bran or outer hull; phytates are also found in tubers, and trace amounts occur in certain fruits and vegetables like berries and green beans. Up to 80 percent of the phosphorus- a vital mineral for bones and health- present in grains is locked into an unusable form as phytate. (F 4) When a diet including more than small amounts of phytate is consumed, the body will bind calcium to phytic acid and form insoluble phytate complexes. The net result is you lose calcium and don't absorb phosphorus. Further, research suggests that we will absorb approximately 20 percent more zinc and 60 percent magnesium from our food when phytate is absent. (F 5)
Seeds and bran are the highest sources of phytates, containing as much as two to five times more phytate than even some varieties of soybeans. They can be difficult to digest unless fermented for long periods.
Phytic Acid Levels in some foods (F 6,7) Figures are in milligrams per 100 grams of dry weight 100% Wheat bran cereal 3,290 Soy beans 1000 - 2,220 Cocoa powder 1684-1796 Oats 1370 Brown rice 1250 Oat flakes 1174 Almond 1138 - 1400 Walnut 982 Lentils 779 Peanut germinated 610 Hazel nuts 648 - 1000 Wild rice flour 634 - 752.5 Refried beans 622 Corn tortillas 448 Corn 367 White flour 258 White flour tortillas 123
Stay tuned for the next installment of "Whole grain toxicity" where we'll look more deeply into the health effects of phytic acid.
Footnotes: 1. Tannenbaum and others. Vitamins and Minerals, in Food Chemistry, 2nd edition. OR Fennema, ed. Marcel Dekker, Inc., New York, 1985, p 445. 2. Ibid. 3. Singh M and Krikorian D. Inhibition of trypsin activity in vitro by phytate. Journal of Agricultural and Food Chemistry 1982 30(4):799-800. 4. Johansen K and others. Degradation of phytate in soaked diets for pigs. Department of Animal Health, Welfare and Nutrition, Danish Institute of Agricultural Sciences, Research Centre Foulum, Tjele, Denmark. 5. Navert B and Sandstrom B. Reduction of the phytate content of bran by leavening in bread and its effect on zinc absorption in man. British Journal of Nutrition 1985 53:47-53; Phytic acid added to white-wheat bread inhibits fractional apparent magnesium absorption in humans1-3. Bohn T and others. American Journal of Clinical Nutrition. 2004 79:418-23. 6. Figures collected from various sources. Inhibitory effect of nuts on iron absoprtion. American Journal of Clinical Nutrition 1988 47:270-4; J Anal At Spectrum. 2004 19,1330-1334; Journal of Agriculture and Food Chemistry 1994, 42:2204-2209. 7. Reddy NR and others. Food Phytates, 1st edition, CRC Press, 2001, pages 30-32