NOW Inositol Powder (8 oz) Inositol is a non-essential member of the B-complex family with dietary sources from both animal and plant foods. The form of inositol used in this product is myo-inositol, the most abundant form of this nutrient. Inositol is found in all cell membranes, with the highest concentrations in the brain and central nervous system, where it plays an important role in neurotransmitter signaling.* Inositol is also critical for the proper action of insulin, lipid metabolism, and for the maintenance of cellular calcium balance.* Supports Healthy Membrane Function* Myo-Inositol Form This product is sold by weight not volume. Natural color variation may occur in this product.