This post was updated on March 13th, 2023
By Kym Campbell, BSc. | Updated March 13th, 2023
Is Ovasitol by Theralogix all it’s cracked up to be?
This product is well-marketed but what’s the truth about its health benefits? Here’s what the science says.
What’s So Special about Ovasitol?
Ovasitol by Theralogix is a market-leading inositol supplement. It contains just two ingredients. Myo-inositol and D-Chiro-inositol. These are both naturally occurring, vitamin-like compounds.
Supplements containing myo-inositol and D-chiro-inositol are effective alternatives to classical insulin sensitizers. As such, they’ve proven useful in preventing and treating metabolic and reproductive disorders .
Many supplements contain either myo-inositol or D-chiro-inositol. A subset of these contains both. Ovasitol is one of a growing number of products that combine these inositol isomers in a specific ratio of 40:1. This formulation is based on the relative levels of these inositols within the human body.
Studies conducted on polycystic ovary syndrome have demonstrated that a 40:1 ratio is best [2-6]. Researchers now believe that many inositol-based treatments for PCOS that don’t use a 40:1 ratio, “lack therapeutic rationale” .
Ovasitol & Weight Loss
Weight loss is one of the most common reasons people consider Ovasitol. But these weight loss benefits are often misunderstood.
Ovasitol and similar inositol supplements have clear benefits for metabolic health. Beyond PCOS, inositol supplementation can prevent or treat metabolic-related diseases. This includes the many disorders associated with insulin resistance and diabetes [8-11].
Myo-inositol may be as effective as metformin when it comes to insulin sensitivity, testosterone levels, and more . In some instances, myo-inositol alone has performed better than metformin [12-14]. Other research has shown that the specific blend of inositol isomers used in Ovasitol is superior to myo-inositol alone [15, 16].
So, Ovasitol is clearly good for your health. But that doesn’t mean it’s a good weight-loss supplement.
As I explain in my article on inositol for PCOS, most scientific trials show modest weight loss results at best. For example, in one trial, a 40:1 inositol supplement resulted in no change in hip-to-waist ratio or BMI over 6 months . In a 3-month trial of myo-inositol, women who were moderately overweight lost approximately two pounds on average. Women that were severely obese didn’t lose any weight at all .
These findings have been replicated consistently. Another 6-month-long study compared three interventions. Diet changes only, diet + myoinositol, and diet + a 40:1 inositol supplement. Women who took the 40:1 inositol supplement lost two pounds more than the women who only changed their diet .
These findings show that Ovasitol causes weight loss. It’s “statistically significant”. But the size of the effect is small.
There are simply much better ways to lose weight. See my article, How to Lose Weight with PCOS, for 15 evidence-based interventions.
Ovasitol & Pregnancy
The use of inositol supplements for improving fertility is well-understood. Many studies have shown that in women with PCOS, myo-inositol improves ovarian function and fertility . Other research has shown that the 40:1 combination used in Ovasitol is best for restoring ovulation. In comparison trials, the 40:1 formulation has performed better than myo-inositol and other ratios of inositol isomers [6, 15, 16].
Ovasitol is particularly valuable for PCOS women undergoing IVF. Many studies have shown that myo-inositol improves egg quality . The number of mature eggs harvested following ovulation induction also increased [20, 21]. This results in better fertilization and pregnancy rates [22, 23]. Inositol supplementation has proven to be at least as good as metformin therapy for improving pregnancy rates [22, 24].
One of the biggest risks of IVF is hyperstimulation syndrome. Myo-inositol-containing supplements can reduce these risks [21, 22]. This is possibly the best reason to include this supplement when undergoing IVF.
Ovasitol is most helpful for insulin-resistant PCOS women. But it may prove valuable for some non-PCOS women too. For example, studies show that fewer gonadotropins are needed when non-PCOS women take myo-inositol . Given the low cost of inositol supplements, this intervention can be justified for financial reasons alone.
Pregnancy Risk Reduction
Ovasitol and other inositol supplements can be valuable interventions for reducing pregnancy risks. By improving insulin sensitivity, these products reduce the risk of developing gestational diabetes [26, 27]. A meta-analysis showed that myo-inositol may also reduce preterm births .
This speaks to the safety of Ovasitol and comparable competitor products.
Ovasitol for Men
Ovasitol was developed for female reproductive health. But it may prove useful for many men as well.
Half of all cases of infertility are due to male factors . The majority of male infertility cases have unknown causes. This problem affects 10−15% of men during their prime reproductive age .
Products like Ovasitol may help treat this problem.
One randomized controlled trial investigated the effects of myo-inositol in infertile men. After 3 months, improvements were seen in sperm concentration, motility, and total count. Reproductive hormone levels were also better . Several other studies further support these findings [32, 33].
Ovasitol may also be useful for the prevention and treatment of autoimmune thyroiditis. This is because myo-inositol, the main ingredient in Ovasitol, has an important role in thyroid function.
Depletion of myo-inositol can cause the development of thyroid diseases like hypothyroidism. Treatment with myo-inositol and selenium supplements can help fix this problem. This is observed in subclinical hypothyroidism cases with or without autoimmune thyroiditis [34, 35].
Ovasitol for PCOS
Since 2016, I’ve followed with interest the studies being done on inositol for PCOS. A lot of new research has been published in the past few years. Compared to other formulations, there’s now significant evidence showing the added value of Ovasitol for PCOS.
Many of the studies included in the weight loss and pregnancy sections above were on PCOS women. This area of medicine is where Ovasitol shows the most promise [36, 37]. Ovasitol improves the body’s balance of myo-inositol and D-chiro inositol. This addresses the underlying hormone dysregulation that characterizes PCOS.
Myo-inositol increases estrogen production while D-chiro-inositol drives androgen (testosterone) synthesis. In PCOS women, elevated insulin levels alter the normal balance of these inositols. Myo-inositol to D-chiro-inositol conversion increases. This results in more testosterone in the ovaries and less active estrogen .
Both myo-inositol and D-chiro-inositol promote follicle-stimulating hormone (FSH) production within the ovary. FSH levels are low in most women with PCOS. By supplementing with a physiological 40:1 ratio of inositols, better hormone balance can be achieved despite a PCOS diagnosis .
It’s understood that products like Ovasitol hold the most promise for overweight PCOS women with insulin resistance . But this supplement also appears to be an effective treatment for normal-weight women with PCOS too.
One study looked at lean women with PCOS that did not have insulin resistance. Patients were given 6-months of 40:1 inositol supplements. Improvements were then seen in ovulation, progesterone levels, and spontaneous pregnancy rates .
Other studies of normal-weight PCOS women have observed reductions in oxidative stress . There also appear to be many benefits for teenagers in preventing and reducing PCOS symptoms .
Other Ovasitol Benefits
Ovasitol and competitor products may have other uses beyond those discussed above. This is because dysfunction of inositol metabolism has been implicated in many chronic diseases. According to one expert opinion, “clinical trials using inositol… provide amazing results in the management of gynecological diseases, respiratory stress syndrome, Alzheimer’s disease, metabolic syndrome, and cancer, for which conventional treatments are disappointing .”
Theralogix provides clear guidance on the appropriate dosage of Ovasitol. One sachet or one “scoop” twice a day is recommended. Each 2.4 g sachet or 2.2 g scoop contains 2,000 mg of myo-inositol and 50 mg of D-Chiro-inositol.
Safety & Side Effects
As noted above, inositol is used to manage gestational diabetes in at-risk pregnancies. This speaks to the safety of products like Ovasitol. D-chiro-inositol taken alone at high dosages may adversely affect egg quality . But at the low levels used in Ovasitol, this isn’t a hazard of concern.
Myo-inositol has proven to be a safe supplement ingredient with few known side effects. One review found only mild gastrointestinal side effects at doses of 12,000 mg/day . This is three times the dose of Ovasitol. Other research has shown that at even higher doses, side effects are mild and gastrointestinal in nature .
The Best Place to Buy Ovasitol Online
Ovasitol is available from a range of online retailers, including Amazon. For the best pricing though, it’s best to buy this supplement direct from Theralogix.
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 the 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. Evitamins is the global distributor for Theralogix.
The Bottom Line
Ovasitol by Theralogix is a popular dietary supplement. This product contains myo-inositol and D-chiro-inositol in a physiological 40:1 ratio. This ratio of inositol isomers is superior to all other formulations for the majority of users. The addition of small amounts of D-chiro-inositol makes Ovasitol better than myo-inositol alone. It’s also better than other products that have different amounts of D-chiro-inositol.
But some claims that Ovasitol helps with weight loss are misleading. A review of the evidence shows that this supplement has excellent insulin-sensitizing effects. This is great for people with insulin resistance or type 2 diabetes. But Ovasitol is not an effective weight loss supplement. While statistically significant, the size of the effect is small.
Ovasitol is most valuable to both men and women that are trying to conceive. The benefits for PCOS women, both before and during pregnancy, are especially well-established. Research also shows the potential for Ovasitol to be used in the treatment of other chronic diseases.
Ovasitol is a safe dietary supplement that is not likely to cause adverse side effects.
Do You Have PCOS?
How long should I take Ovasitol for? A single order of Ovasitol is enough for a 90-day supply. This is the shortest recommended duration for taking this supplement. The best results are usually seen after 6 months.
What’s the difference between Ovasitol and inositol? Inositol is the general name for nine vitamin-like compounds within the same family of molecules. Ovasitol is a proprietary inositol supplement manufactured by Theralogix. This product contains two types of inositol, myo-inositol, and D-chiro-inositol.
Does Ovasitol help with hairloss? There’s little evidence to support this claim. Many other supplements are more likely to help with hairloss .
Are there benefits of taking Ovasitol without PCOS? Yes. Ovasitol is an effective treatment for disorders associated with insulin resistance and diabetes [8-11]. These common health issues extend well beyond the PCOS population. Ovasitol may be useful for treating idiopathic male factor infertility. It can also be used to treat and prevent autoimmune thyroiditis.
Is Ovasitol FDA approved? No. FDA approval is not required for dietary supplements like Ovasitol.
Do I need an Ovasitol prescription? No. Prescriptions are not required for dietary supplements like Ovasitol. The Dietary Supplement Act of 1994 (DSHEA) considers dietary supplements as “foods”.
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.
Quick Disclosure: Some of the links on this page may be affiliate links. This means that when you use them to purchase something, it won't cost you more but I may get paid a commission for referring you. In order to avoid any prejudice, I only recommend products that I personally use or would have recommended anyways.
1Dinicola, S., et al., Inositols: From Established Knowledge to Novel Approaches. Int J Mol Sci, 2021. 22(19).
2Bevilacqua, 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.
3Facchinetti, 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.
4Kamenov, Z. and A. Gateva, Inositols in PCOS. Molecules, 2020. 25(23).
5Monastra, 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.
6Nordio, 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.
7Roseff, S. and M. Montenegro, Inositol Treatment for PCOS Should Be Science-Based and Not Arbitrary. Int J Endocrinol, 2020. 2020: p. 6461254.
8Bizzarri, M., et al., Pharmacodynamics and pharmacokinetics of inositol(s) in health and disease. Expert Opin Drug Metab Toxicol, 2016. 12(10): p. 1181-96.
9Croze, M.L. and C.O. Soulage, Potential role and therapeutic interests of myo-inositol in metabolic diseases. Biochimie, 2013. 95(10): p. 1811-27.
10Facchinetti, F., et al., Experts’ opinion on inositols in treating polycystic ovary syndrome and non-insulin dependent diabetes mellitus: a further help for human reproduction and beyond. Expert Opin Drug Metab Toxicol, 2020. 16(3): p. 255-274.
11Kiani, A.K., et al., From Myo-inositol to D-chiro-inositol molecular pathways. Eur Rev Med Pharmacol Sci, 2021. 25(5): p. 2390-2402.
12Jamilian, 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.
13Soldat-Stankovic, V., et al., THE EFFECT OF MYOINOSITOL AND METFORMIN ON CARDIOVASCULAR RISK FACTORS IN WOMEN WITH POLYCYSTIC OVARY SYNDROME: A RANDOMIZED CONTROLLED TRIAL. Acta Endocrinol (Buchar), 2021. 17(2): p. 241-247.
14Zhao, H., et al., Comparative efficacy of oral insulin sensitizers metformin, thiazolidinediones, inositol, and berberine in improving endocrine and metabolic profiles in women with PCOS: a network meta-analysis. Reprod Health, 2021. 18(1): p. 171.
15Nordio, 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.
16Unfer, V. and G. Porcaro, Updates on the myo-inositol plus D-chiro-inositol combined therapy in polycystic ovary syndrome. Expert Rev Clin Pharmacol, 2014. 7(5): p. 623-31.
17Gerli, 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.
18Le 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.
19Merviel, P., et al., Impact of myo-inositol treatment in women with polycystic ovary syndrome in assisted reproductive technologies. Reprod Health, 2021. 18(1): p. 13.
20Garg, D. and R. Tal, Inositol Treatment and ART Outcomes in Women with PCOS. Int J Endocrinol, 2016. 2016: p. 1979654.
21Papaleo, 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.
22Regidor, P.A., et al., Management of women with PCOS using myo-inositol and folic acid. New clinical data and review of the literature.Horm Mol Biol Clin Investig, 2018. 34(2).
23Zheng, 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.
24Raffone, 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.
25Laganà, A.S., et al., Myo-inositol supplementation reduces the amount of gonadotropins and length of ovarian stimulation in women undergoing IVF: a systematic review and meta-analysis of randomized controlled trials. Arch Gynecol Obstet, 2018. 298(4): p. 675-684.
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.
28Vitagliano, A., et al., Inositol for the prevention of gestational diabetes: a systematic review and meta-analysis of randomized controlled trials. Arch Gynecol Obstet, 2019. 299(1): p. 55-68.
29de Kretser, D.M., Male infertility. Lancet, 1997. 349(9054): p. 787-90.
30Kothandaraman, N., et al., Pathogenic landscape of idiopathic male infertility: new insight towards its regulatory networks. NPJ Genom Med, 2016. 1: p. 16023.
31Calogero, A.E., et al., Myoinositol improves sperm parameters and serum reproductive hormones in patients with idiopathic infertility: a prospective double-blind randomized placebo-controlled study. Andrology, 2015. 3(3): p. 491-5.
32Condorelli, R.A., et al., Myo-inositol as a male fertility molecule: speed them up! Eur Rev Med Pharmacol Sci, 2017. 21(2 Suppl): p. 30-35.
33Vazquez-Levin, M.H. and G.L. Verón, Myo-inositol in health and disease: its impact on semen parameters and male fertility. Andrology, 2020. 8(2): p. 277-298.
34Pace, C., et al., Role of selenium and myo-inositol supplementation on autoimmune thyroiditis progression. Endocr J, 2020. 67(11): p. 1093-1098.
35Paparo, S.R., et al., Myoinositol in Autoimmune Thyroiditis. Front Endocrinol (Lausanne), 2022. 13: p. 930756.
36Gateva, A., V. Unfer, and Z. Kamenov, The use of inositol(s) isomers in the management of polycystic ovary syndrome: a comprehensive review. Gynecol Endocrinol, 2018. 34(7): p. 545-550.
37Zeng, L. and K. Yang, Effectiveness of myoinositol for polycystic ovary syndrome: a systematic review and meta-analysis. Endocrine, 2018. 59(1): p. 30-38.
38Unfer, V., et al., Altered Ovarian Inositol Ratios May Account for Pathological Steroidogenesis in PCOS. Int J Mol Sci, 2020. 21(19).
39Colak, E., et al., May myo-inositol and d-chiro-inositol (40:1) treatment be a good option on normal-weighted polycystic ovary syndrome patients without insulin resistance? J Obstet Gynaecol Res, 2020.
40Donà, G., et al., Inositol administration reduces oxidative stress in erythrocytes of patients with polycystic ovary syndrome. Eur J Endocrinol, 2012. 166(4): p. 703-10.
41Pkhaladze, L., et al., Treatment of lean PCOS teenagers: a follow-up comparison between Myo-Inositol and oral contraceptives. Eur Rev Med Pharmacol Sci, 2021. 25(23): p. 7476-7485.
42Vitagliano, A., et al., “Empiric” inositol supplementation in normal-weight non insulin resistant women with polycystic ovarian disease: from the absence of benefit to the potential adverse effects. Arch Gynecol Obstet, 2015. 291(5): p. 955-7.
43Carlomagno, G. and V. Unfer, Inositol safety: clinical evidences. Eur Rev Med Pharmacol Sci, 2011. 15(8): p. 931-6.
44Lam, S., et al., A phase I study of myo-inositol for lung cancer chemoprevention. Cancer Epidemiol Biomarkers Prev, 2006. 15(8): p. 1526-31.
45Hosking, A.M., M. Juhasz, and N. Atanaskova Mesinkovska, Complementary and Alternative Treatments for Alopecia: A Comprehensive Review. Skin Appendage Disord, 2019. 5(2): p. 72-89.