Inositol is necessary for the formation of lecithin and functions closely with a B complex vitamin, Choline. Since it is not essential in the human diet, it cannot be considered a vitamin. Inositol is a fundamental ingredient of cell membranes and is necessary for proper function of nerves, brain, and muscles in the body. Inositol works in conjunction with folacin, Vitamins B-6 and B-12, choline, betaine, and methionine to prevent the accumulation of fats in the liver. It exists as the fiber component phytic acid, which has been investigated for its anti-cancer properties.