What is inositol? Structurally similar to glucose, 100% Inositol is a vitamin-like compound which is an important component of cell membranes and cellular signalling. It can be found in both animals and plants, or made in a laboratory. Often referred to as vitamin B8, inositol is not actually a vitamin, but a carbocyclic sugar, which is common in high quantities in tissues. Your kidneys produce roughly 2g of inositol each day, but the highest concentration of inositol can be found in your brain, where it is involved in the function of your brain’s chemical messengers. What is myo-inositol? There are numerous types of inositol, with two commonly used forms being myo-inositol and D-chiro-inositol (DCI). Myo-inositol is the most common form of inositol and it is found in most plants and animals. Myo-inositol was previously considered to be a member of vitamin B complex, vitamin B8. It is no longer deemed to be an essential nutrient, as your body can produce inositol itself from glucose. A nutrient is only regarded as essential if it cannot be produced by the body and has to be sourced from elsewhere.