Updated March 2020
by Amy Medling, founder of PCOS Diva
Like many women with Polycystic Ovarian Syndrome (PCOS), I work hard to keep my blood sugar balanced, cycles regular, and testosterone levels low through diet, lifestyle, and supplements. For a while, I also took inositol in the form of D-chiro-inositol in the morning and Myo-inositol in the evening with good results.
I have replaced this regimen with one product. Ovasitol (from Theralogix) was the first product available which combines two important types of inositol, myo-inositol (MYO) and D-chiro-inositol (DCI), in one package. Its unique combination of two important inositols in a ratio that matches our body’s natural levels, is on the cutting edge of PCOS research, and many agree that, together with diet and exercise, it should be a “first line” approach to promote menstrual regularity and normal ovarian function. That is why I have now included it in the PCOS Diva Discover (foundational) tier of supplements. In fact, at the dose of 4000 mg/100 mg per day, is significantly less expensive than all the other brands of 40:1 products, and it is the only NSF certified one on the market. That means they are regularly inspected for quality and contents. I feel confident taking Ovasitol because, like the PCOS Diva products, there is a third party assuring that I get exactly what is on the label.
What is inositol?
Inositol has been a hot topic of discussion for some time. For some background, you can refer to my previous articles, interviews, and research here. In a nutshell, inositol is not a drug; it is a class of B-vitamins that naturally occur in many of the foods we consume such as fruits, legumes, vegetables, nuts, buckwheat, and beans.
Two of the 9 forms of inositol (MYO and DCI) have special insulin sensitizing capabilities and are important “second messengers” for insulin receptors. You will notice that supplement dosages of MYO are always higher than for DCI; that is because your body converts MYO into DCI. These inositols are critical players in insulin signaling, and the disruption in this signaling, due to a lack of one or the other, leads researchers to believe that inositol is a key component in insulin resistance.
Unfortunately, women with PCOS have a breakdown in this process. Our bodies have difficulty converting inositol from our food into MYO and DCI, or we excrete too much DCI and cannot produce enough to replace it. This causes the breakdown in insulin processing. This situation is even more likely if you have first-degree diabetic relatives. (19)
As you may know, insulin resistance (IR) triggers increased testosterone. IR and high testosterone are common symptoms in women with PCOS, which cascade into a host of hormone related health issues ranging from difficulty with fertility to acne and hair loss.
Studies have shown that women with PCOS who take an inositol supplement each day will reduce their insulin resistance, improve their hormone levels, and have more regular menstrual cycles. Inositol supplementation also supports normal lipid (blood fat) levels and promotes egg quality in women trying to become pregnant.
In addition, inositol is a lipotropic agent which helps your body remove fats from your organs and blood. While inositol is most commonly thought of for restoring menstrual cycles and fertility, replacing clomiphene or metformin, current research promises a role well beyond these symptoms.
What does Myo-inositol do?
An ovarian deficiency in MYO has been linked closely to PCOS. MYO supplementation seems to help alleviate common PCOS symptoms such as insulin resistance and ovarian function issues.
In fact, MYO has been shown to improve insulin resistance and egg quality, and may reduce the risk of gestational diabetes. A 2007 study in Italy found that, “MYO is a simple and safe treatment that is capable of restoring spontaneous ovarian activity and consequently fertility in most patients with PCOS.” In another study, after only 12 weeks, patients had improved insulin sensitivity and androgen levels and returned to normal menstrual cycles. Later, in a double-blind study, researchers discovered that when given MYO, patients’ ovulation increased and they returned to normal progesterone levels.
Studies also find that subjects receiving MYO saw decreases in testosterone, triglycerides and blood pressure.
In addition, it has been linked to the activation of serotonin receptors which may help lessen appetite, depression, and anxiety while it improves mood.
While benefits were less dramatic with obese women, they did lose a significant amount of weight and lowered leptin levels. In summary, supplying extra MYO seems to correct malfunctioning pathways and alleviate these common PCOS symptoms.
For those trying to conceive, another important 2017 study found that, “Myo-inositol has proven to be a new treatment option for patients with PCOS and infertility. The achieved pregnancy rates are at least in an equivalent or even superior range than those reported using metformin as an insulin sensitizer. No moderate to severe side effects were observed when myo-inositol was used at a dosage of 4000 mg per day. In addition, evidence suggests that a myo-inositol therapy in women with PCOS results in better fertilization rates and a clear trend to a better embryo quality.” (23) Later, a 2019 study found that, “the 40:1 MI/DCI ratio is the best for PCOS therapy aimed at restoring ovulation and normalizing important parameters in these patients. The other formulations were less effective.” (25)
What does D-chiro-inositol do?
Just like MYO, DCI plays a key role in mediating the action of the insulin receptor. There is evidence that in the peripheral tissues of women with PCOS, not enough DCI is produced from MYO, leading to a relative deficiency of DCI. This may be what causes women with PCOS to develop insulin resistance.
Insulin resistance causes many issues, including high blood sugar, high insulin levels, high androgen levels, and the production of too much testosterone. The excess testosterone cascades into further symptoms including belly fat, facial hair, hair loss, acne and lack of ovulation. Increasing DCI in the peripheral tissues has been widely proven to address many of these issues, as well as improve ovulatory function (though MYO is more effective with ovulation).
D-Chiro-inositol works its magic by increasing “the action of insulin in patients with the polycystic ovary syndrome, thereby improving ovulatory function and decreasing serum androgen concentrations, blood pressure, and plasma triglyceride concentrations .”
Studies show that in women with PCOS, replacing the lost DCI with a supplement, “improved their insulin resistance and clinical features.” Caution is necessary with DCI; women with PCOS appear to actually have too much DCI in their ovarian tissue, so supplementing higher doses (600-2400 mg daily) of DCI “progressively worsens oocyte quality and ovarian response.”
Why put MYO and DCI together?
As with so many things in your body, it is all about balance. The natural ratio of MYO to DCI in your plasma is 40:1. The goal is to maintain that ratio for optimal performance. Adding too much of one or the other will throw off your balance and then you are back to square one.
Studies show that, “MI/DCI in a combination reproducing the plasma physiological ratio (40:1), represents a promising alternative in achieving better clinical results, by counteracting PCOS at both systematic and ovary level.” In fact, a recent study revealed that, “Myo-inositol+D-chiro-inositol showed significantly better results in terms of weight reduction, resumption of spontaneous ovulation, and spontaneous pregnancy than Metformin in polycystic ovary syndrome patients.”
In addition, women with PCOS undergoing IVF may especially benefit, whereas one study found that, “only the combined therapy was able to improve oocyte and embryo quality as well as pregnancy rates.”
So in summary, “The combined administration of MI and DCI in physiological plasma ratio (40:1) should be considered as the first line approach on PCOS overweight patients, being able to reduce the metabolic and clinical alteration of PCOS and, therefore, reduce the risk of metabolic syndrome.” In fact, the greatest benefit to controlling insulin resistance no matter your weight comes with the balanced (40:1 ratio) and combined use of Myo & D-chiro insositols. (19, 20, 21, 22)
Are there any side effects to taking inositol?
The short answer is no. Occasionally, at a very high dose of MYO, one may experience mild GI side effects such as nausea, gas or diarrhea. It should not interact with your other medications or supplements. During pregnancy and while breastfeeding, you may continue taking inositol, and studies show that it may reduce gestational diabetes. As always, please consult your healthcare team before beginning any medication or supplement.
Inositol vs. Metformin
Many women with PCOS cannot tolerate metformin or want a more natural alternative. Increasingly, studies are showing that, like berberine and/or inositols perform as well or better than metformin in normalizing androgenic (hormone) and metabolic (insulin) levels.
Moreover, inositol had almost no risk of adverse effects that often accompany metformin.
Caution: If you currently take metformin, speak with your doctor before taking Ovasitol since the combined effect may lower blood sugar levels too much. (24)
Where can I find MYO and DCI together?
Ovasitol (by Theralogix) has become a foundational supplement for women searching for a natural way to promote menstrual regularity and normal ovarian function.* Ovasitol was the first “combined inositol” supplement for women with PCOS and remains the most trusted.
Not only does it combine MYO and DCI, but it does so at an ideal ratio, mimicking healthy blood plasma. This optimal combination will improve insulin sensitivity and promote normal hormone levels which can restore menstrual regularity and enhance ovary function.
Ovasitol is 100% pure inositol (no maltodextrin or fillers) and contains 100mg of DCI and 4000 mg of MYO (40:1 ratio). The DCI is a purposefully lower dose since new research indicates that the 600 mg dose may be too high.
Ovasitol does not contain folic acid since if you are pregnant or trying to conceive, that is already in your prenatal vitamin, and too much can be damaging. I do not advocate supplementing with folic acid at any rate; I suggest using folate. This is one reason I do not suggest the inositol supplement Pregnitude. For more information on folic acid vs. folate, read my article here.
My former regimen of Ovaboost and Chiral Balance was $263.85 ($86.85 for Ovaboost and $177 for Chiral Balance) for 3 months. Ovasitol costs $65 for the same time-frame (plus there is always free shipping on Ovasitol at the PCOS Diva Store).
When I am at home, I use the canister version of Ovasitol. It is a little less expensive ($65 for a 3 month supply), and I can quickly add it to my morning smoothie or tea. I also like individual serving packet version of Ovasitol ($78 for 3 month supply). These little packets are still tasteless, odorless, and dissolve easily in water, so I can slip it in my purse and mix it into my water bottle when I am ready!
I am confident taking Ovasitol because it is produced in a thoughtful way by a reputable company. Theralogix formulated Ovasitol with an advisory board of leading reproductive specialists, and it was vetted by NSF® International (a non-profit certification program) for purity, content accuracy and freedom from contaminants. Inositols are relatively unregulated nutritional supplements. This means there is no one monitoring for variance between batches of a product or even contamination by other substances. Voluntary third party monitoring reassures me of Theralogix’s commitment to a quality product.
A healthy PCOS diet and lifestyle are always required for optimal health, but in a case like this when our body’s systems cannot derive nutrients from the food we eat, supplements are definitely a good choice.
I encourage you to talk to your health care team about adding Ovasitol to your regimen. Work on inositols is cutting edge, and these studies are small. Your health care team may be unfamiliar with the research. Take information with you to share, and take control of your health.
If you are interested in ordering Ovasitol, you may do so here and automatically receive the lowest price available and FREE shipping.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
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