This post was updated on September 8th, 2022
By Kym Campbell, BSc. | Updated September 8th, 2022
Ovasitol by Theralogix is the market leader in PCOS inositol products.
I was once skeptical of the added value of Ovasitol compared to other formulations. In this article, I explain why I changed my mind. I now recommend this product to women that take part in my free 30-Day PCOS Diet Challenge and Beat PCOS 10-Week Program.
The Benefits Of Inositol
Inositol supplements are well-studied in PCOS settings. As I’ve written about in detail here, inositol has the following benefits:
- Inositol improves insulin sensitivity and hormone balance in both lean and overweight women with PCOS [1-4].
- Myo-inositol may be as good as metformin for improving insulin sensitivity and testosterone [5, 6].
- Myo-inositol aids fertility by improving ovarian function and increasing egg quality [7-9].
- Studies on women receiving fertility treatments have shown increases in pregnancy rates [10-13]. Supplementation also reduces the risk of ovarian hyperstimulation syndrome .
- Myo-inositol has also been shown to have modest benefits for acne , hirsutism , and weight loss [7, 16]. The size of the effect here is not likely to be life-changing though.
There are ingredients to be wary of when choosing products. And there are some types of inositol you may want to limit when trying to conceive. But if a product contains 4,000 mg/day of myo-inositol, then there are health benefits to be had.
Criticism Of 40:1 Formulations
Ovasitol by Theralogix is a combination product. It contains 40 parts of myo-inositol for every 1-part D-chiro-inositol. Dosing is 2,000 mg of myo-inositol + 50 mg of D-chiro-inositol, taken twice daily.
Both Theralogix and the scientific community have long said that a 40:1 ratio is the best for PCOS [17-19].
Back in 2017, I was skeptical of this claim. When I looked at the data, all these perspectives were informed by only two randomized controlled trials [20, 21]. Each with shortcomings and limitations.
Other experts had noted that a 40:1 ratio, “seems arbitrary”. They also said that “without further scientific evidence, the 40:1 ratio has no reason to be considered preferable to other available formulations” .
A 2019 study dampened these concerns.
The Study That Changed My Mind
Nordio and colleagues tested various ratios of myo- and D-chiro inositol in women with PCOS. They looked at ratios of 1:3.5, 2.5:1, 5:1, 40:1, and 80:1. They also tested D-chiro inositol alone. Out of all these combinations, they found that a 40:1 formulation was best at restoring ovulation and improving fertility . This randomized, open-label comparison trial made me change my mind.
I now think that products like Ovasitol are the best formulation for women with PCOS. Ovasitol’s 40:1 ratio of inositol isomers has been demonstrated in mouse models of PCOS. It’s also been tested in other clinical trials [23-25].
Cheapest Places To Buy Ovasitol
You can buy Ovasitol on Amazon. Many pharmacies also stock it. For the best deal though, you should buy it directly from your local distributor.
USA: US customers can buy Ovasitol from Theralogix here. Use the link provided or type in the Provider Referral Code (PRC) A29927 at checkout, for $10 off the retail price.
Canada: Canadian customers can purchase Ovasitol directly from Theralogix Canada here. Use the link provided or type in discount code KYM at checkout for $10 off the retail price. Please note that your discount will only show up at the final stage of checkout.
Everywhere Else: Everyone else can order Ovasitol from evitamins.com, the global distributor for Theralogix.
When Is Inositol Worth Taking?
If you’re struggling with infertility or insulin resistance, then inositol supplements are worth considering.
When used as directed, inositol supplements are safe. So much so, that women with PCOS are sometimes advised to take myo-inositol during pregnancy [26-28]. The ingredients used in Ovasitol are naturally present in the body. This means that the downside risk is low. It’s also fairly affordable, as results are typically observed within 3 – 6 months.
How To Enhance The Benefits Of Ovasitol For PCOS
Dietary supplements like Ovasitol are only one of many evidence-based PCOS natural treatments. The way to get the best results with Ovasitol is to change your diet too. This helps address the underlying mechanisms that cause PCOS. Switching to the best macros for PCOS, for example, can reverse insulin resistance. Eliminating foods like gluten, dairy, and sugar reduces inflammation. While each change on its own is small, collectively, they make a big difference.
The Bottom Line
Ovasitol is a safe and effective PCOS treatment. While the marketing claims are many, there is good scientific evidence supporting its use. Recent evidence shows that the 40:1 formulation used in Ovasitol is superior to competitor products. For PCOS women struggling with infertility or insulin resistance, then inositol supplements are well worth considering.
Whether you take inositol or not, dietary change is essential for getting your PCOS in check. Start this process by signing up for my next free 30-Day PCOS Diet Challenge. Or begin today with this free 3-Day Meal Plan.
Ready To Take Action?
What is the Ovasitol dosage for PCOS? Ovasitol comes in powdered form either in a canister or in individual packets. A single dose is one leveled scoop from the canister, or one packet.
How long do I need to take Ovasitol? At least 3 months is recommended. By 6 months, most benefits will be realized. Discontinuation may cause symptoms to return unless you’ve made diet and lifestyle changes in the meantime.
Do I need a prescription for Ovasitol? No. Inositol is a nutritional supplement that’s available over-the-counter.
What are the side effects? No relevant adverse effects were found in several studies that used 4000 mg per day of myo-inositol throughout pregnancy [28, 29].
Can I take Ovasitol with Metformin? Myo-inositol-containing supplements can improve insulin sensitivity as much as metformin [5, 6]. Caution is warranted when taking both of these medicines together. Your metformin dose may need to be reduced or ceased.
Since 2010, Kym Campbell has used evidence-based diet and lifestyle interventions to manage her PCOS. After getting her symptoms under control and falling pregnant naturally, Kym now advocates for dietary change as part of any PCOS treatment plan. Combining rigorous science and clinical advice with a pragmatic approach to habit change, Kym is on a mission to show other women how to take back control of their health and fertility. Read more about Kym and her team here.
1Kamenov, Z. and A. Gateva, Inositols in PCOS. Molecules, 2020. 25(23).
2Unfer, V., et al., Effects of myo-inositol in women with PCOS: a systematic review of randomized controlled trials. Gynecol Endocrinol, 2012. 28(7): p. 509-15.
3Iuorno, M.J., et al., Effects of d-chiro-inositol in lean women with the polycystic ovary syndrome. Endocr Pract, 2002. 8(6): p. 417-23.
4Laganà, A.S., L. Barbaro, and A. Pizzo, Evaluation of ovarian function and metabolic factors in women affected by polycystic ovary syndrome after treatment with D-Chiro-Inositol. Arch Gynecol Obstet, 2015. 291(5): p. 1181-6.
5Facchinetti, F., et al., Short-term effects of metformin and myo-inositol in women with polycystic ovarian syndrome (PCOS): a meta-analysis of randomized clinical trials. Gynecol Endocrinol, 2019. 35(3): p. 198-206.
6Jamilian, M., et al., Comparison of myo-inositol and metformin on clinical, metabolic and genetic parameters in polycystic ovary syndrome: A randomized controlled clinical trial. Clin Endocrinol (Oxf), 2017. 87(2): p. 194-200.
7Gerli, S., et al., Randomized, double blind placebo-controlled trial: effects of myo-inositol on ovarian function and metabolic factors in women with PCOS. Eur Rev Med Pharmacol Sci, 2007. 11(5): p. 347-54.
8Ciotta, L., et al., Effects of myo-inositol supplementation on oocyte’s quality in PCOS patients: a double blind trial. Eur Rev Med Pharmacol Sci, 2011. 15(5): p. 509-14.
9Papaleo, E., et al., Myo-inositol may improve oocyte quality in intracytoplasmic sperm injection cycles. A prospective, controlled, randomized trial. Fertil Steril, 2009. 91(5): p. 1750-4.
10Zheng, X., et al., Inositol supplement improves clinical pregnancy rate in infertile women undergoing ovulation induction for ICSI or IVF-ET. Medicine (Baltimore), 2017. 96(49): p. e8842.
11Artini, P.G., et al., Endocrine and clinical effects of myo-inositol administration in polycystic ovary syndrome. A randomized study. Gynecol Endocrinol, 2013. 29(4): p. 375-9.
12Raffone, E., P. Rizzo, and V. Benedetto, Insulin sensitiser agents alone and in co-treatment with r-FSH for ovulation induction in PCOS women. Gynecol Endocrinol, 2010. 26(4): p. 275-80.
13Emekçi Özay, Ö., et al., Myo-inositol administration positively effects ovulation induction and intrauterine insemination in patients with polycystic ovary syndrome: a prospective, controlled, randomized trial. Gynecol Endocrinol, 2017. 33(7): p. 524-528.
14Zacchè, M.M., et al., Efficacy of myo-inositol in the treatment of cutaneous disorders in young women with polycystic ovary syndrome. Gynecol Endocrinol, 2009. 25(8): p. 508-13.
15Minozzi, M., G. D’Andrea, and V. Unfer, Treatment of hirsutism with myo-inositol: a prospective clinical study. Reprod Biomed Online, 2008. 17(4): p. 579-82.
16Le Donne, M., et al., Effects of three treatment modalities (diet, myoinositol or myoinositol associated with D-chiro-inositol) on clinical and body composition outcomes in women with polycystic ovary syndrome. Eur Rev Med Pharmacol Sci, 2019. 23(5): p. 2293-2301.
17Dinicola, S., et al., The rationale of the myo-inositol and D-chiro-inositol combined treatment for polycystic ovary syndrome. J Clin Pharmacol, 2014. 54(10): p. 1079-92.
18Genazzani, A.D., Inositol as putative integrative treatment for PCOS. Reprod Biomed Online, 2016. 33(6): p. 770-780.
19Monastra, G., et al., Combining treatment with myo-inositol and D-chiro-inositol (40:1) is effective in restoring ovary function and metabolic balance in PCOS patients. Gynecol Endocrinol, 2017. 33(1): p. 1-9.
20Nordio, M. and E. Proietti, The combined therapy with myo-inositol and D-chiro-inositol reduces the risk of metabolic disease in PCOS overweight patients compared to myo-inositol supplementation alone. Eur Rev Med Pharmacol Sci, 2012. 16(5): p. 575-81.
21Colazingari, S., et al., 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, 2013. 288(6): p. 1405-1411.
22Sortino, M.A., et al., Polycystic Ovary Syndrome: Insights into the Therapeutic Approach with Inositols. Front Pharmacol, 2017. 8: p. 341.
23Nordio, M., S. Basciani, and E. Camajani, 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): p. 5512-5521.
24Roseff, S. and M. Montenegro, Inositol Treatment for PCOS Should Be Science-Based and Not Arbitrary. Int J Endocrinol, 2020. 2020: p. 6461254.
25Bevilacqua, A., et al., Myo-inositol and D-chiro-inositol (40:1) reverse histological and functional features of polycystic ovary syndrome in a mouse model. J Cell Physiol, 2019. 234(6): p. 9387-9398.
26D’Anna, R., et al., Myo-Inositol for the Prevention of Gestational Diabetes Mellitus. A Brief Review. J Nutr Sci Vitaminol (Tokyo), 2019. 65(Supplement): p. S59-s61.
27Sobota-Grzeszyk, A., M. Kuźmicki, and J. Szamatowicz, Myoinositol in the Prevention of Gestational Diabetes Mellitus: Is It Sensible? J Diabetes Res, 2019. 2019: p. 3915253.
28D’Anna, R., et al., Myo-inositol may prevent gestational diabetes in PCOS women. Gynecol Endocrinol, 2012. 28(6): p. 440-2.
29Regidor, P.A. and A.E. Schindler, Myoinositol as a Safe and Alternative Approach in the Treatment of Infertile PCOS Women: A German Observational Study. Int J Endocrinol, 2016. 2016: p. 9537632.