While no specific deficiencies have been found in relation to diseases, some people may benefit from supplementation.

Natural Sources: Beans, Cantaloupe, Nuts, Oranges, Wheat, Wheat Bran contain phytic acid, which releases inositol when acted upon by the bacteria of the digestive system.

Useful in treatment of:
Depression: Small studies have found inositol helpful for depression.^1,2 In one such trial, 28 depressed individuals were given a daily dose of 12g of inositol for 4 weeks.³ By the fourth week, the group receiving inositol showed significant improvement compared to the placebo group. Further studies are needed to confirm this.

Panic Disorder: A study of 21 participants found that people given 12g of inositol daily had fewer, and less severe, panic attacks as compared to the placebo group.⁴ Again, further studies are needed to confirm this.

Diabetes: Two uncontrolled studies have shown mixed results in the use of inositol for complications of diabetes, specifically diabetic neuropathy.⁵

Recommended Dosage: 500 mg twice daily for diabetic neuropathy; doses up to 12 grams per day have been used for neuropsychiatric problems.

Contraindications: Some inositol supplements have a dairy base. People with food allergies should be aware of this fact. No long-term safety studies have been performed. Safety has not been established in young children, women who are pregnant or nursing, and those with severe liver and kidney disease.

References:
¹Levine J, Barak Y, Kofman O, and Belmaker RH. Follow-up and relapse analysis of an inositol study of depression. Isr J Psychiatry Relat Sci 32(1): 14–21, 1995.
²Levine J. Controlled trials of inositol in psychiatry. Eur Neuropsychopharmacol 7: 147–155, 1997.
³Benjamin J, Agam G, Levine J, et al. Inositol treatment in psychiatry. Psychopharmacol Bull 31(1): 167–175, 1995.
⁴Benjamin J, Levine J, Fux M, et al. Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder. Am J Psychiatry 152: 1084–1086, 1995.
⁵Salway JG, Whitehead L, Finnegan JA, et al. Effect of myo-inositol on peripheral-nerve function in diabetes. Lancet 1978;II:1282–84.