A natural sugar found in cell membrane phospholipids, plasma lipoproteins, and (as the phosphate form) in the nucleus with potential chemopreventive properties. As one of a number of intracellular phosphate compounds, inositol is involved in cell signaling and may stimulate tumor cell differentiation. (NCI04)

A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Myoinositol helps cells make membranes and respond to messages from their environment. It has the same chemical formula as glucose (the chief source of energy for living organisms) but has a different arrangement of atoms. It is found in beans, peas, brown rice, wheat bran and nuts. It is water-soluble (can dissolve in water) and must be taken in every day. Myoinositol is being studied in the prevention of cancer.

An isomer of glucose that has traditionally been considered to be a B vitamin although it has an uncertain status as a vitamin and a deficiency syndrome has not been identified in man. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1379) Inositol phospholipids are important in signal transduction.

Cyclic sugar alcohol, the fully hydroxylated derivative of cyclohexane, occurring naturally in a variety of stereoisomers, most commonly, the myo-isomer, myoinositol, a member of the vitamin B complex and a component of phosphatidylinositols.