40:1 Myo and D-Chiro Inositol vs Myo-Inositol
How 40:1 myo and D-chiro inositol and myo-inositol differ in potency, absorption, tolerance, and cost.
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Side by Side
| Myo-Inositol and D-Chiro-Inositol (40:1) | Myo-Inositol | |
|---|---|---|
| Absorption | Moderate | Moderate |
| How it is absorbed | Combines both isomers in roughly the ratio found in plasma. Absorption is that of each component. | Absorbed by sodium-dependent transporters shared with glucose; gram doses are needed because the body already makes and holds grams. |
| Typical dose | 2 g myo plus 50 mg DCI, twice daily | 2-4 g daily; 12-18 g in psychiatric trials |
| Common uses | PCOS | PCOS, gestational diabetes prevention, panic disorder (older trials) |
| Side effects | As for myo-inositol. | Nausea, gas, and loose stools at high doses. |
| Cost | Moderate | Low |
| Also called | 40:1 blend, Ovasitol | inositol, myo-inositol powder |
When to Choose Myo-Inositol and D-Chiro-Inositol (40:1)
Choose 40:1 myo and D-chiro inositol when you want the ratio tested in PCOS combination trials. The 40:1 ratio performed best for ovulation among ratios compared in one trial; myo-inositol alone remains the better-studied option.
Myo-Inositol and D-Chiro-Inositol (40:1)
Convenient for PCOS, with one trial supporting the ratio. Myo-inositol alone remains the better-studied option.
What to look for: 2 g myo-inositol and 50 mg D-chiro-inositol per serving, ratio stated.
Find on iHerb Affiliate linkWhen to Choose Myo-Inositol
Choose myo-inositol when you want the form with the PCOS and psychiatric trial data. Unqualified "inositol" on a label is myo-inositol. Inositol hexanicotinate is a niacin compound, not an inositol supplement.
Myo-Inositol
The form behind nearly all of the PCOS and psychiatric data, and cheap as a powder.
What to look for: Pure myo-inositol powder or 2 g sachets. Grams per serving on the panel.
Find on iHerb Affiliate linkProducts on Titrate
8,650 of the 214,745 labels in the NIH Dietary Supplement Label Database list inositol as an active ingredient (3,697 on market). 389 are sold as inositol products by name.
Inositol does not have its own search category yet. Each product above links to its full label in the NIH database.
Related
References
Unfer V, Carlomagno G, Dante G, Facchinetti F. Effects of myo-inositol in women with PCOS: a systematic review of randomized controlled trials. Gynecol Endocrinol. 2012;28(7):509-515.
Unfer V, Facchinetti F, Orrù B, Giordani B, Nestler J. Myo-inositol effects in women with PCOS: a meta-analysis of randomized controlled trials. Endocr Connect. 2017;6(8):647-658.
Nordio M, Basciani S, Camajani E. The 40:1 myo-inositol/D-chiro-inositol plasma ratio is able to restore ovulation in PCOS patients: comparison with other ratios. Eur Rev Med Pharmacol Sci. 2019;23(12):5512-5521.
Isabella R, Raffone E. Does ovary need D-chiro-inositol? J Ovarian Res. 2012;5(1):14.
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Palatnik A, Frolov K, Fux M, Benjamin J. Double-blind, controlled, crossover trial of inositol versus fluvoxamine for the treatment of panic disorder. J Clin Psychopharmacol. 2001;21(3):335-339.
Mukai T, Kishi T, Matsuda Y, Iwata N. A meta-analysis of inositol for depression and anxiety disorders. Hum Psychopharmacol. 2014;29(1):55-63.