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    Inositol

    Inositol

    Uses

    What Are Star Ratings?

    Our proprietary "Star-Rating" system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.

    For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.

    3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.

    2 Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.

    1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.

    This supplement has been used in connection with the following health conditions:

    Used for Why
    2 Stars
    Anxiety
    4 to 6 grams three times per day
    Inositol has been used to help people with anxiety who have panic attacks.

    Inositol has been used to help people with anxiety who have panic attacks. Up to 4 grams three times per day was reported to control such attacks in a double-blind trial.1 Inositol (18 grams per day) has also been shown in a double-blind trial to be effective at relieving the symptoms of obsessive-compulsive disorder.2

    2 Stars
    Depression
    12 grams of inositol daily
    People with depression may have lower levels of inositol. Supplementing with this nutrient may correct a deficiency and improve depression symptoms.

    Preliminary evidence indicates that people with depression may have lower levels of inositol .3 Supplementation with large amounts of inositol can increase the body's stores by as much as 70%.4 In a double-blind trial, depressed people who received 12 grams of inositol per day for four weeks had a significant improvement in symptoms compared to those who took placebo.5 In a double-blind follow-up to this trial, the antidepressant effects of inositol were replicated. Half of those who responded to inositol supplementation relapsed rapidly when inositol was discontinued.6

    1 Star
    Bipolar Disorder
    Refer to label instructions
    Inositol may be useful for treating depression in people with bipolar disorder.

    Inositol is a nutrient found in large amounts in the brain, but its possible role in mood disorders is unclear. Inositol levels may be reduced in certain parts of the brains of depressed and bipolar patients.7 However, lithium reduces normal brain levels of inositol, and this may be one of the ways lithium helps people with bipolar disorder.8 , 9 , 10 Although inositol is known to have significant antidepressant properties when administered in large amounts of 12 grams per day,11 , 12 case reports involving bipolar patients have reported either no benefit,13 some benefit,14 or worsening of symptoms from inositol supplementation.15 Until controlled research clarifies the effects of inositol in people with bipolar illness, it should only be used under the supervision of a qualified healthcare practitioner.

    1 Star
    Type 1 Diabetes
    Refer to label instructions
    Supplementing with inositol may improve diabetic neuropathy.
    Inositol is needed for normal nerve function. Diabetes can cause a type of nerve damage known as diabetic neuropathy. Certain measures of the severity of this condition have been reported to improve with inositol supplementation (500 mg taken twice per day);16 however, in other trials, inositol was ineffective.17
    1 Star
    Type 2 Diabetes
    Refer to label instructions
    Supplementing with inositol may improve diabetic neuropathy.
    Inositol is needed for normal nerve function. Diabetes can cause a type of nerve damage known as diabetic neuropathy. This condition has been reported in some, but not all, trials to improve with inositol supplementation (500 mg taken twice per day).18

    How It Works

    How to Use It

    Most people do not need to take inositol. In addition, the small amounts commonly found in multivitamin supplements are probably unnecessary and ineffective. Doctors sometimes suggest 500 mg twice per day. For depression , anxiety , and obsessive-compulsive disorder, 12-18 grams per day has been shown to be effective in double-blind trials.19 , 20 , 21 , 22

    Where to Find It

    Nuts, beans, wheat and wheat bran, cantaloupe, and oranges are excellent sources of inositol. Most dietary inositol is in the form of phytate .

    Possible Deficiencies

    Clear deficiency of inositol has not been reported, although people with diabetes have increased excretion and may benefit from inositol supplementation.

    Interactions

    Interactions with Supplements, Foods, & Other Compounds

    At the time of writing, there were no well-known supplement or food interactions with this supplement.

    Interactions with Medicines

    Certain medicines interact with this supplement.

    Types of interactions: Beneficial Adverse Check

    Replenish Depleted Nutrients

    • none

    Reduce Side Effects

    • none

    Support Medicine

    • none

    Reduces Effectiveness

    • none

    Potential Negative Interaction

    • none

    Explanation Required

    • Lithium

      Lithium therapy has been shown to deplete brain stores of inositol.23 While it has been suggested that inositol supplementation (e.g., 500 mg three times daily) could reduce adverse effects of lithium therapy without reducing the drug's therapeutic effectiveness,24 , 25 the safety and efficacy of this combination has not been proven.

      Treatment with lithium can trigger or worsen psoriasis . In a double-blind study, supplementing with inositol (6 grams per day) for ten weeks significantly improved lithium-induced psoriasis, but had no effect on psoriasis in people who were not taking lithium.26

    The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers' package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a supplement with your doctor or pharmacist.

    Side Effects

    Side Effects

    Toxicity has not been reported, although people with chronic renal failure show elevated levels and should not take inositol, except under medical supervision.

    Large amounts of phytate , the common dietary form of inositol, reduce the absorption of calcium , iron , and zinc . However, supplemental inositol does not have this effect.

    One review article suggested that inositol may stimulate uterine contractions.27 While no research has demonstrated that inositol actually has this effect, women who are or could become pregnant should consult a doctor before taking inositol.

    References

    1. Benjamin J, Levine J, Fux M, et al. Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder. Am J Psychiatry 1995;152:1084-6.

    2. Fux M, Levine J, Aviv A, Belmaker RH. Inositol treatment of obsessive-compulsive disorder. Am J Psychiatry 1996;153:1219-21.

    3. Barkai AI, Dunner DL, Gross HA, et al. Reduced myo-inositol levels in cerebrospinal fluid from patients with affective disorder. Biol Psychiatry 1978;13:65-72.

    4. Levine J, Rapaport A, Lev L. Inositol treatment raises CSF inositol levels. Brain Res 1993;627:168-70.

    5. Levine J, Barak Y, Gonzalves M, et al. Double-blind, controlled trial of inositol treatment of depression. Am J Psychiatry 1995;152:792-4.

    6. Levine J, Barak Y, Kofman O, Belmaker RH. Follow-up and relapse analysis of an inositol study of depression. Isr J Psychiatry Relat Sci 1995;32:14-21.

    7. Shimon H, Agam G, Belmaker RH, et al. Reduced frontal cortex inositol levels in postmortem brain of suicide victims and patients with bipolar disorder. Am J Psychiatry 1997;154:1148-50.

    8. Fauroux CM, Freeman S. Inhibitors of inositol monophosphatase. J Enzyme Inhib 1999;14:97-108 [review].

    9. Belmaker RH, Agam G, van Calker D, et al. Behavioral reversal of lithium effects by four inositol isomers correlates perfectly with biochemical effects on the PI cycle: depletion by chronic lithium of brain inositol is specific to hypothalamus, and inositol levels may be abnormal in postmortem brain from bipolar patients. Neuropsychopharmacology 1998;19:220-32 [review].

    10. Belmaker RH, Bersudsky Y, Agam G, et al. How does lithium work on manic depression? Clinical and psychological correlates of the inositol theory. Annu Rev Med 1996;47:47-56 [review].

    11. Levine J, Barak Y, Gonzalves M, et al. Double-blind, controlled trial of inositol treatment of depression. Am J Psychiatry 1995;152:792-4.

    12. Levine J, Barak Y, Kofman O, Belmaker RH. Follow-up and relapse analysis of an inositol study of depression. Isr J Psychiatry Relat Sci 1995;32:14-21.

    13. Souza FG, Mander AJ, Foggo M, et al. The effects of lithium discontinuation and the non-effect of oral inositol upon thyroid hormones and cortisol in patients with bipolar affective disorder. J Affect Disord 1991;22:165-70.

    14. Grisaru N, Belmaker RH. Lithium dosage and inositol levels. Br J Psychiatry 1994;164:133-4 [letter].

    15. Levine J, Witztum E, Greenberg BD, Barak Y. Inositol-induced mania? Am J Psychiatry 1996;153:839 [letter].

    16. Salway JG, Whitehead L, Finnegan JA, et al. Effect of myo-inositol on peripheral-nerve function in diabetes. Lancet1978;2:1282-4.

    17. Gregersen G, Borsting H, Theil P, Servo C. Myoinositol and function of peripheral nerves in human diabetics. Acta Neurol Scand 1978;58:241-8.

    18. Salway JG, Whitehead L, Finnegan JA, et al. Effect of myo-inositol on peripheral-nerve function in diabetes. Lancet 1978;2:1282-4.

    19. Levine J, Barak Y, Gonzalves M, et al. Double-blind, controlled trial of inositol treatment of depression. Am J Psychiatry 1995;152:792-4.

    20. Levine J, Barak Y, Kofman O, Belmaker RH. Follow-up and relapse analysis of an inositol study of depression. Isr J Psychiatry Relat Sci 1995;32:14-21.

    21. Benjamin J, Levine J, Fux M, et al. Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder. Am J Psychiatry 1995;152:1084-6.

    22. Fux M, Levine J, Aviv A, Belmaker RH. Inositol treatment of obsessive-compulsive disorder. Am J Psychiatry 1996;153:1219-21.

    23. Silverstone PH, Rotzinger S, Pukhovsky A, Hanstock CC. Effects of lithium and amphetamine on inositol metabolism in the human brain as measured by 1H and 31P MRS. Biol Psychiatry 1999;46:1634-1.

    24. Colodny L, Hoffman RL. Inositol -- Clinical applications for exogenous use. Altern Med Rev 1998;3:432-47.

    25. Johnson EC, Gray-Keller MP, O'Day PM. Rescue of excitation by inositol following Li(+)-induced block in Limulus ventral photoreceptors. Vis Neurosci 1998;15:105-12.

    26. Allan SJR, Kavanagh GM, Herd RM, Savin JA. The effect of inositol supplements on the psoriasis of patients taking lithium: a randomized, placebo-controlled trial. Br J Dermatol 2004;150:966-9.

    27. Colodny L, Hoffman RL. Inositol-Clinical applications for exogenous use. Altern Med Rev 1998;3:432-47.

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