Inositol for PCOS: A Supplement That Really Works?

Written by Angie Arriesgado
happy women out in the sunshine - probably happy that supplementing with inositol for PCOS worked for them

Polycystic ovarian syndrome (PCOS) affects women from all walks of life. It may not be life-threatening, but if left untreated it can progress to more serious medical conditions like type II diabetes and cardiovascular problems. In this article, you’ll find out if supplementing with inositol for PCOS is an effective treatment option.

What Exactly Is Inositol?

Inositol is a naturally occurring form of sugar that is commonly found in grains, fruits, and nuts. Oranges and cantaloupes are two examples of fruits with high inositol content. Our body also makes inositol from glucose, so it’s not at all foreign to us. In fact, our kidneys make around two grams of inositol per day.  

Inositol is a major component in our cell membranes. It affects neurotransmitters in the brain, including the mood hormones serotonin and dopamine. And it helps with blood sugar control thanks to its effect on insulin.

There are 9 isomeric forms of inositol, with myo-inositol being the most common form. It can turn into other forms such as d-chiro-inositol when the body requires it (1). You’ll learn more about how myo-inositol and d-chiro-inositol work together to fight PCOS, so keep on reading!

Powdered inositol tastes half as sweet as table sugar. It makes for a suitable “cocaine” prop on movie sets. So, the next time you see your favorite actor snorting powder on a table, it’s probably inositol!

insulin resistance can cause pcos

PCOS and Insulin Resistance

Traditionally, treating PCOS meant treating individual symptoms. That is, you get a prescription for the lack of period or the hair loss or the weight gain, etc. However, the root cause is often left untreated.

That said, the root cause of PCOS is still unknown, but there are a few theories out there. One is that it’s a hereditary condition that’s further compounded by obesity (2). Another is when female babies are exposed to high levels of androgens in utero which makes them prone to getting PCOS later in life (3). And lastly, insulin resistance or insulin insensitivity (4). For this article, we’ll focus on treating insulin resistance to reverse PCOS symptoms.

But what does insulin have to do with PCOS?

Insulin is a hormone that converts the carbohydrates from the foods you eat into sugar or glucose, so the body can use it for energy. It regulates your blood sugar levels by storing excess glucose in your liver, muscles, and fat cells. The body then uses this stored glucose when your blood sugar levels go down, maybe because you’re hungry or you’ve had strenuous physical activity that used up tons of energy (5).  

However, when you eat too many carbs without expending the same amount of energy (e.g. due to a sedentary lifestyle), your blood sugar levels can stay dangerously high. Your pancreas makes more insulin to try and get your blood sugar levels down.

But increased insulin levels for prolonged periods lead to insulin resistance, that is, insulin no longer works as it should. So, blood sugar levels go unmanaged. This can then develop into serious medical conditions like type II diabetes, blindness, kidney failure, and heart disease.

Hormone levels get skewed because of insulin resistance. Your estrogen levels drop and your testosterone (the male hormone) levels go up. This is why many PCOS symptoms present as typical male characteristics. For example, unwanted hair growth on the face (beard, mustache), irregular or loss of menstruation, and thinning hair at the top of your head just like male pattern baldness (6).

how supplementing with inositol helps with PCOS

How Inositol Helps With PCOS

Here are a few ways inositol can help women affected by PCOS:

Reduce insulin resistance

Costantino and colleagues did a double-blind study on 42 women with PCOS. They treated half of the women with myo-inositol plus folic acid. The other half took folic acid. The difference between the two groups was astounding. The first group showed a marked increase in insulin sensitivity, lower blood pressure, lower triglyceride level, and lower testosterone levels versus the second group (7).

Related article: Can Omega-3 Improve Insulin Sensitivity?

Improve egg quality

Egg quality can spell the difference between a healthy pregnancy and a problematic one. Women with PCOS not only suffer from irregular periods and infertility, but poor egg quality is also a problem. Fortunately, supplementing with myo-inositol improves egg quality in PCOS patients, which leads to a healthy pregnancy (8).

Prevent gestational diabetes

Pregnant women who suffer from insulin resistance are at high risk of developing gestational diabetes mellitus (GDM). However, myo-inositol supplementation may help reduce the probability of developing GDM. The women also gave birth to smaller and healthier babies at a later gestational age (9).

Improve blood pressure and triglyceride levels

Myo-inositol is the main inositol in the body. But a study done on d-chiro-inositol showed that in addition to helping improve insulin sensitivity in PCOS patients, it also lowered the women’s plasma triglyceride concentrations. Additionally, the patients’ diastolic and systolic blood pressure decreased significantly as well (10).

Lowers testosterone levels

High testosterone levels are responsible for the bad acne, thinning hair, and hirsutism in women with PCOS. If you suffer from these symptoms, then consider taking inositol for PCOS. In a double-blind trial, researchers were able to see significant reduction in testosterone levels by treating women with a combination of myo-inositol and folic acid (7).

the best inositol supplement to treat PCOS symptoms

Taking Inositol Supplements for PCOS – What’s The Best Option?

Consuming large amounts of inositol-rich foods every single day may help with PCOS, but you’d need to be pretty disciplined about it. That means no cheating or binging on unhealthy and sugar-rich foods. This is why supplementing with inositol is becoming necessary. Oftentimes, getting inositol from food is just not enough to improve insulin sensitivity.

Fortunately, inositol is a natural and safe alternative to synthetic drugs like Metformin, which is frequently prescribed for those with insulin resistance. However, Metformin does have some side effects, including preventing the absorption of vitamin B12. A deficiency in B12 can cause lasting nerve damage (11). We recommend you consider a safer alternative instead, such as an inositol supplement.


There may not be a cure for PCOS yet, but its symptoms are manageable. Living a healthy lifestyle – eating a PCOS-friendly diet and being more physically active – can help improve your symptoms. Supplementing with inositol also helps. To ensure your symptoms never make a comeback, it’s important to commit to this new lifestyle.