Page 30 - Spring2010

of phytates, containing as much as two to five they take in, but after several weeks on this diet, they reach a balance and
times more phytate than even some varieties of do not excrete excess calcium. However, no studies of this phenomenon
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soybeans, which we know are highly indigestible have been carried out over a long period; nor have researchers looked at
unless fermented for long periods. Remember whether human beings can adjust to the phytate-reducing effects of other
the oat bran fad? The advice to eat bran, or high important minerals, such as iron, magnesium and zinc.
fiber foods containing different types of bran, The zinc- and iron-blocking effects of phytic acid can be just as
is a recipe for severe bone loss and intestinal serious as the calcium-blocking effects. For example, one study showed
problems due to the high phytic acid content. that a wheat roll containing 2 mg phytic acid inhibited zinc absorption by
Raw unfermented cocoa beans and normal 18 percent; 25 mg phytic acid in the roll inhibited zinc absorption by 64
cocoa powder are extremely high in phytates. percent; and 250 mg inhibited zinc absorption by 82 percent. Nuts have
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Processed chocolates may also contain phytates. a marked inhibitory action on the absorption of iron due to their phytic
White chocolate or cocoa butter probably does acid content. 13
not contain phytates. More evidence is needed Over the long term, when the diet lacks minerals or contains high
as to phytate content of prepared chocolates and levels of phytates or both, the metabolism goes down, and the body goes
white chocolate. Coffee beans also contain phytic into mineral-starvation mode. The body then sets itself up to use as little of
acid. The chart in Figure 1 shows the variability these minerals as possible. Adults may get by for decades on a high-phytate
of phytate levels in various common foods as a diet, but growing children run into severe problems. In a phytate-rich diet,
percentage of dry weight. Phytate levels in terms their bodies will suffer from the lack of calcium and phosphorus with poor
of milligrams per hundred grams are shown in bone growth, short stature, rickets, narrow jaws and tooth decay; and for
Figure 2. the lack of zinc and iron with anemia and mental retardation.

DETRIMENTAL EFFECTS THE EXPERIMENTS OF EDWARD MELLANBY
High-phytate diets result in mineral deficien- As early as 1949, the researcher Edward Mellanby demonstrated the
cies. In populations where cereal grains provide a demineralizing effects of phytic acid. By studying how grains with and
major source of calories, rickets and osteoporosis without phytic acid affect dogs, Mellanby discovered that consumption
are common. of high-phytate cereal grain interferes with bone growth and interrupts
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Interestingly, the body has some ability to vitamin D metabolism. High levels of phytic acid in the context of a diet
adapt to the effects of phytates in the diet. Several low in calcium and vitamin D resulted in rickets and a severe lack of bone
studies show that subjects given high levels of formation.
whole wheat at first excrete more calcium than His studies showed that excessive phytate consumption uses up vi-

PHYTATES: A BENEFICIAL ROLE?

As evidence of the detrimental effects of phytates accumulates, reports on alleged beneficial effects have also emerged.
In fact, a whole book, Food Phytates, published in 2001 by CRC press, attempts to build a case for “phytates’ potential
ability to lower blood glucose, reduce cholesterol and triacylglycerols, and reduce the risks of cancer and heart disease.” 14
One argument for the beneficial effects of phytates is based on the premise that they act as anti-oxidants in the body.
But recent studies indicate that an overabundance of anti-oxidants is not necessarily a good thing as these compounds
will inhibit the vital process of oxidation, not only in our cells but also in the process of digestion.
Another theory holds that phytates bind to extra iron or toxic minerals and remove them from the body, thus acting as
chelators and promoting detoxification. As with all anti-nutrients, phytates may play a therapeutic role in certain cases.
For example, researchers claim that phytic acid may help prevent colon cancer and other cancers. Phytic acid is
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one of few chelating therapies used for uranium removal. 16
Phytic acid’s chelating effect may serve to prevent, inhibit, or even cure some cancers by depriving those cells of the
minerals (especially iron) they need to reproduce. The deprivation of essential minerals like iron would, much like other
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broad treatments for cancer, also have negative effects on non-cancerous cells. For example, prolonged use of phytic
acid to clear excess iron may deprive other cells in the body that require iron (such as red blood cells).
One theory is that phytates can help patients with kidney stones by removing excess minerals from the body. How-
ever, a long-term study involving over forty-five thousand men found no correlation between kidney stone risk and dietary
intake of phytic acid. 18
Phytates also have the potential for use in soil remediation, to immobilize uranium, nickel and other inorganic con-
taminants. 19
30 Wise Traditions SPRING 2010