Inositol

What is inositol?

Inositol is a nonessential nutrient, a carbohydrate or, more specifically, a sugar alcohol that can be produced in your body from glucose, so you do not need to get it from foods in order to be healthy ^[1,10]. Two most common naturally occurring forms of inositol are myo-inositol and D-chiro-inositol.

Inositol Formula

Picture 1. Inositol structure

Inositol Functions in the Human Body

• Inositol helps to build cell membranes ^[1].
• Myo-inositol acts as a secondary messenger in the nervous system; it increases the effect of neurotransmitters ^[1].
• D-chiro-inositol and myo-inositol increase the insulin sensitivity.

Foods Rich in Myo-Inositol

• PLANT FOODS: beans, peas, rutabaga, okra, wheat and oat bran, whole grains, cantaloupe, citrus fruits, blackberries, nectarine, kiwi ^[3]
• OTHER FOODS: energy drinks

D-Chiro-Inositol Deficiency

In one study, individuals with diabetes 2 (non-insulin dependent diabetes) had lower excretion of D-chiro inositol in the urine and lower D-chiro inositol content in muscles than healthy people ^[4].

Inositol Supplements

Nonprescription oral inositol supplements are available in the following forms:

• Inositol
• Myo-inositol
• D-chiro-inositol
• Inositol choline

Inositol Health Benefits

Myo-inositol is POSSIBLY EFFECTIVE in:

• Lowering triglyceride and testosterone levels, improving insulin sensitivity and improving fertility in polycystic ovary syndrome (PCOS) ^{[5,11,13,14,15]}. NOTE: Unlike for myo-inositol, there is INSUFFICIENT EVIDENCE about the effectiveness of D-chiro-inositol in increasing insulin sensitivity in women with PCOS ^[12]
• Acute respiratory distress syndrome (ARDS) in preterm infants ^[5,19,21]
• Psoriasis triggered by lithium (a drug used in bipolar disorder) ^[5,16,17,18]

Inositol is POSSIBLY INEFFECTIVE ^[5,7] in the prevention or treatment of Alzheimer’s disease, autism, nerve damage (neuropathy) in diabetes ^[3] and schizophrenia.

There is INSUFFICIENT EVIDENCE ^[5] about the effectiveness of inositol in the prevention or treatment of anxiety, attention deficit-hyperactivity disorder (ADHD) ^[7], binge eating and bulimia nervosa ^[22], cancer, depression ^[20], high cholesterol, insomnia, obsessive-compulsive disorder (OCD) ^[5,7,24,25], panic disorder ^[5,7,24,26], premenstrual dysphoric disorder (PMDD) ^[8,23] and Raynaud’s syndrome ^[9] or in promoting hair growth.

Inositol Safety: Side Effects, Toxicity

Inositol is POSSIBLY SAFE for most adults, and for treatment of infants with acute respiratory distress syndrome ^[5].

Side effects may include nausea, tiredness, headache and dizziness ^[5].

Not enough is known about the safety of inositol supplements during pregnancy and breastfeeding, so women in these periods should avoid them.

Inositol-Drug Interactions

There are no known inositol-drug interactions ^[5].