Inositol (myo-inositol) is a cyclic polyol, contained in cereals, nuts and fruits; human organism is able to produce it endogenously. Inositol is in fact an intermediate of the synthesis of phospho-inositides and inositol phosphoglycans and it is considered as an insulin-sensitizing agent, that is a molecule that enhances insulin effect on peripheral target cells, stimulating uptake of glucose. Thus supplementation with inositol is helpful to moderate symptoms of insulin resistance and of hyperglycemia, regulating body glucose management.