the high phytate content of whole grains binds to minerals such as iron, calcium, magnesium, and zinc in the gastrointestinal tract, significantly reducing their absorption by the body
Effects of dietary fiber and phytic acid on mineral availability
It has long been recognized that high cereal grain consumption induces vitamin D deficiency in various animal species, including primates, our closest animal relatives. By studying the fate of radio-labelled vitamin D, researchers observed significantly increased excretion of vitamin D in healthy human volunteers fed sixty grams of wheat fiber daily.
Comparative vitamin B-6 bioavailability from tuna, whole wheat bread and peanut butter.
http://www.ncbi.nlm.nih.gov/pubmed/6655507
the high phytate content of whole grains binds to minerals such as iron, calcium, magnesium, and zinc in the gastrointestinal tract, significantly reducing their absorption by the body
http://www.sciencedirect.com/science/article/pii/S0140673673...
EFFECTS OF PURIFIED PHYTATE AND PHYTATE-RICH BREAD UPON METABOLISM OF ZINC, CALCIUM, PHOSPHORUS, AND NITROGEN IN MAN
http://www.ncbi.nlm.nih.gov/pubmed/1657026
Effects of dietary fiber and phytic acid on mineral availability
It has long been recognized that high cereal grain consumption induces vitamin D deficiency in various animal species, including primates, our closest animal relatives. By studying the fate of radio-labelled vitamin D, researchers observed significantly increased excretion of vitamin D in healthy human volunteers fed sixty grams of wheat fiber daily.
http://www.ncbi.nlm.nih.gov/pubmed/6299329
Reduced plasma half-life of radio-labelled 25-hydroxyvitamin D3 in subjects receiving a high fiber diet.
Full analysis:
http://anthonycolpo.com/the-whole-grain-scam/