Which Inositol is Best for People With PCOS?

Studies show that inositol may help manage PCOS symptoms and may even improve fertility, but which inositol is the best?

By OBGYN Dr. Kenosha Gleaton

The most common endocrine disorder among reproductive aged women, PCOS often has a negative impact on fertility. Research shows that taking a myo-inositol supplement can improve ovarian function and reduce androgen levels, two of the primary causes for PCOS symptoms. Read on to uncover the uses and benefits of inositol for PCOS.

What’s PCOS again?

Polycystic ovarian syndrome (PCOS) affects about 1 in 10 women of reproductive age. In order to be diagnosed, two out of three symptoms of PCOS must be present. These include:

• increased male hormones (called androgens)
• irregular release of eggs (aka ovulation)
• more than 12 follicles (or cysts) on each ovary on ultrasound.

PCOS presentation can vary widely: some PCOS patients have no symptoms, while others can experience weight gain, hair growth, hair loss, acne, irregular menstrual cycle or missed periods, and infertility.

Why inositol is useful for people with PCOS

Inositol, often cited as Myo-inositol (MI) and D-chiro-inositol (DCI), is a supplement that can be used to improve glucose levels and insulin resistance. This is helpful for those with PCOS, as insulin resistance is found in 30-40% of PCOS patients. While using inositol to manage PCOS remains experimental, many studies suggest inositol can decrease insulin resistance, improve ovarian function and egg quality, and reduce androgen levels. 

How long does it take to work?

There is no uniform agreement on duration of treatment. Trying to conceive with PCOS? Since inositol is considered overall safe when TTC and during pregnancy, it may be worthwhile to consider adding this to your regimen after discussing with your OBGYN if it’s right for you.

Different types- MI/DCI

There are actually nine different types, or isomers, of inositol. The two most commonly used for PCOS treatment include Myo-inositol supplementation (MI) and D-chiro-inositol (DCI). Studies suggest that both forms of inositol treatment are important —MI for improving ovulation function, and DCI for reducing insulin levels.

Ideal ratio

The most researched and naturally occurring ratio of MI:DCI is thought to be 40:1. When administered at this concentration, plasma concentrations are mimicked and PCOS is counteracted at both systemic and ovarian levels.

It is important to note that a Cochrane review warns there aren’t enough quality studies on this to prove inositol improves pregnancy rate or live birth for PCOS patients.

Take-aways

• PCOS is the most common endocrine disorder for reproductive-aged women.
• To diagnose PCOS, two out of three symptoms must be present. These symptoms include high levels of androgens, irregular ovulation, and a certain number of cysts on each ovary.
• Inositol can help improve PCOS by reducing androgens and enhancing ovarian function
• There are nine different types of inositol, but MI and DCI are the most commonly used.
• A 40:1 ratio of MI/DCI is thought to be the most effective for treatment.

Sources:

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