What is inositol and how does it work in the body?
Inositol is a vitamin-like compound found in many foods and also synthesized by the body itself. Although sometimes called vitamin B8, it is not technically a vitamin.
Inositol acts as an intracellular second messenger — it helps hormones (especially insulin and serotonin) transmit their signals to cells. Without inositol, cells cannot properly receive hormonal signals.
Two main forms:
- Myo-inositol (MI) — ~90% of body's inositol, most researched
- D-chiro-inositol (DCI) — present in smaller amounts, important for insulin signaling
Why is inositol important for hormonal balance?
The strongest scientific evidence for inositol relates to PCOS (polycystic ovary syndrome), affecting up to 10% of women of reproductive age.
Unfer et al. (2017) meta-analysis of 10 studies:
- Myo-inositol supports ovulation function
- Contributes to androgen balance
- Supports normal insulin sensitivity
- Contributes to menstrual cycle regularity
Pizzo et al. (2014):
- 50 women with PCOS
- 4g myo-inositol + 400mcg folic acid for 6 months
- Menstrual cycle regularity improved in study participants
- The study observed changes in androgen levels
How does inositol help with anxiety and mood?
Benjamin et al. (1995):
- 18g inositol daily was associated with changes in individuals with panic disorder
- Inositol influences serotonin signaling
- Without significant side effects
Palatnik et al. (2001):
- 12g inositol daily for 4 weeks
- The study observed changes in anxiety levels
Inositol affects serotonin receptors and helps:
- Reduce anxiety
- Alleviate panic attacks
- Support stable mood
- Support overall mental wellbeing
What is the optimal ratio of myo-inositol to D-chiro-inositol?
Research has shown that the body's natural MI:DCI ratio is 40:1.
Why the ratio matters:
- Too much DCI can impair egg quality
- The 40:1 ratio mimics the body's natural balance
- Best clinical outcomes achieved with this ratio
Practical example: 4000mg myo-inositol + 100mg D-chiro-inositol
Colazingari et al. (2013):
- 40:1 ratio vs DCI alone in women with PCOS
- 40:1 ratio produced better outcomes for ovulation and hormonal profile
- DCI alone at high doses worsened egg quality
Who benefits from inositol and how to dose it?
| Goal | Form | Dose | Duration |
|---|---|---|---|
| PCOS | MI + DCI (40:1) | 4g MI + 100mg DCI | 3+ months |
| Anxiety | MI | 2-4g/day | 4-8 weeks |
| Panic disorders | MI | 12-18g/day | 4+ weeks |
| Insulin sensitivity | MI + DCI | 2-4g MI/day | Ongoing |
| Fertility | MI + DCI (40:1) | 4g MI + 100mg DCI | 3+ months |
Split daily dose into two — morning and evening.
Side effects (rare):
- Mild nausea
- Bloating at high doses
- Very safe supplement
Explore our inositol selection and find the right product.
Summary
Inositol is a well-researched and safe supplement:
- PCOS: Supports ovulation function, contributes to hormonal balance
- Anxiety: Influences serotonin signaling, supports mood
- Insulin: Supports normal insulin sensitivity
- Fertility: Supports egg quality
- Ratio: Choose 40:1 myo-inositol:D-chiro-inositol
- Dose: 2-4g myo-inositol daily
References
- Unfer V, Facchinetti F, Orrù B, et al. (2017). Myo-inositol effects in women with PCOS: a meta-analysis of randomized controlled trials. Endocrine Connections, 6(8), 647-658.
- Pizzo A, Laganà AS, Barbaro L. (2014). Comparison between effects of myo-inositol and D-chiro-inositol on ovarian function and metabolic factors in women with PCOS. Gynecological Endocrinology, 30(3), 205-208.
- Benjamin J, Levine J, Fux M, et al. (1995). Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder. The American Journal of Psychiatry, 152(7), 1084-1086.
- Palatnik A, Frolov K, Fux M, Benjamin J. (2001). Double-blind, controlled, crossover trial of inositol versus fluvoxamine for the treatment of panic disorder. Journal of Clinical Psychopharmacology, 21(3), 335-339.
- Colazingari S, Treglia M, Blasi P, et al. (2013). The combined therapy myo-inositol plus D-chiro-inositol, rather than D-chiro-inositol, is able to improve IVF outcomes: results from a randomized controlled trial. Archives of Gynecology and Obstetrics, 288(6), 1405-1411.
