D-chiro inositol is a natural human metabolite, meaning that the human body can ordinarily make it from the food it ingests. This makes it one of the safest substances around.
D-chiro inositol is part of a group of substances collectively referred to as inositol which is a part of the B Vitamin family. Inositol is a type of carbohydrate which is formed by 6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms. Interestingly, the same number and type of atoms, when arranged differently can form glucose! There are many different types of inositol, all with a slightly different arrangement of the atoms. Myo-inositol is one of the most common and it is this form that you are most likely to find in the health food shops, usually sold in a combination with choline as they work well together.
D-chiro inositol is a component of an inositol phosphoglycan which enhances the way insulin works in the body, making it more effective. A deficiency in d-chiro inositol or DCI containing inositol phosphoglycan (DCI-IPG) can be a contributing factor to a person developing insulin resistance. This is because some actions of insulin are affected by DCI-IPG mediators.