Answer: Inositol hexaphosphate (IP6), more commonly known as phytic acid or phytate (the salt form), is a naturally-occurring compound. It is a source of phosphate in many plants and is abundant in foods such as cereals, grains and legumes.
IP6 is not digestible by people; in fact, it can chelate minerals in the gut, inhibiting their absorption. Only ruminant animals, such as cattle and sheep, that produce the enzyme phytase, are able to digest IP6.
IP6 alone does not appear to have been used in any clinical studies. However, it has been used in combination with inositol (also known as myo-inositol) in preliminary studies and there is one report of this combination used by a man with stage IV metastatic melanoma who, as reported by his doctors at the Mayo Clinic, entered remission. Do not confuse inositol hexaphosphate with inositol hexanicotinate — a form of niacin found in some supplements.
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