This post was updated on April 4th, 2023
By Kym Campbell, BSc. | Updated April 4th, 2023
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.
To start putting a PCOS diet into practice, sign-up for my next free 30-Day PCOS Diet Challenge. Or get started today with this free 3-Day Meal Plan.
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.
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.
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