What is it? Overview Usage Side Effects and Warnings

What is Inositol?

Inositol, unofficially referred to as "vitamin B 8 ," is present in all animal tissues, with the highest levels in the heart and brain. It is part of the membranes (outer coverings) of all cells, and plays a role in helping the liver process fats as well as contributing to the function of muscles and nerves.

Inositol may also be involved in depression. People who are depressed may have lower than normal levels of inositol in their spinal fluid. In addition, inositol participates in the action of serotonin, a neurotransmitter known to be a factor in depression. (Neurotransmitters are chemicals that transmit messages between nerve cells.) For these two reasons, inositol has been proposed as a treatment for depression, and preliminary evidence suggests that it may be...

Some but not all studies suggest that high-dose inositol may be useful for depression . 1 2 3 Inositol has also been studied for bipolar disorder , 4 panic disorder , 5 bulimia , 6 and obsessive-compulsive disorder , 7 but the evidence remains far from conclusive. Other potential uses include Alzheimer's disease 8 and attention deficit disorder . 9 According to two double-blind studies enrolling a total of almost 400 people, inositol may help improve various symptoms of polycystic ovary syndrome , including infertility and weight gain. 10 Another very small double-blind study found that inositol supplements could help reduce symptoms of psoriasis triggered or made worse by use of the drug lithium . 11 A small double-blind study failed to find...

Safety Issues

No serious ill effects have been reported for inositol, even with a therapeutic dosage that equals about 18 times the average dietary intake. However, no long-term safety studies have been performed.

Although inositol has sometimes been recommended for bipolar disorder, there is evidence to suggest inositol may trigger manic episodes in people with this condition. 12 If you have bipolar disorder, you should not take inositol unless under a doctor's supervision.

Safety has not been established in young children, women who are pregnant or nursing, and those with severe liver and kidney disease. As with all supplements used in very large doses, it is important to purchase a reputable product, because a contaminant present even in small percentages could add up to a real...