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.
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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!
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 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).
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 may also help. To ensure your symptoms never make a comeback, it’s important to commit to this new lifestyle.
(1) D-chiro-inositol glycans in insulin signaling and insulin resistance, Joseph Larner, David L Brautigan, Michael O Thorner, Mol Med. 2010 Nov-Dec;16(11-12):543-52.
(2) Molecular progress in infertility: polycystic ovary syndrome, Richard S Legro, Jerome F Strauss, Fertil Steril. 2002 Sep;78(3):569-76.
(3) Is foetal hyperexposure to androgens a cause of PCOS? Panagiota Filippou, Roy Homburg Human Reproduction Update, Volume 23, Issue 4, July-August 2017, Pages 421–432.
(4) Impaired glucose tolerance, type 2 diabetes and metabolic syndrome in polycystic ovary syndrome: a systematic review and meta-analysis, Lisa J. Moran, Marie L. Misso, Robert A. Wild, Robert J. Norman, Human Reproduction Update, Volume 16, Issue 4, July-August 2010, Pages 347–363.
(5) Insulin and insulin resistance, Gisela Wilcox, Clin Biochem Rev. 2005 May;26(2):19-39.
(6) The Mechanism of Androgen Actions in PCOS Etiology, Valentina Rodriguez Paris, Michael J Bertoldo, Med Sci (Basel). 2019 Aug 28;7(9):89.
(7) Metabolic and hormonal effects of myo-inositol in women with polycystic ovary syndrome: a double-blind trial, D Costantino, G Minozzi, E Minozzi, C Guaraldi, Eur Rev Med Pharmacol Sci. 2009 Mar-Apr;13(2):105-10.
(8) Inositol supplement improves clinical pregnancy rate in infertile women undergoing ovulation induction for ICSI or IVF-ET, Xiangqin Zheng, Danmei Lin, Yulong Zhang, Yuan Lin, Jianrong Song, Suyu Li, Yan Sun, Medicine (Baltimore). 2017 Dec;96(49):e8842.
(9) Effect of dietary myo-inositol supplementation in pregnancy on the incidence of maternal gestational diabetes mellitus and fetal outcomes: a randomized controlled trial, Barbara Matarrelli, Ester Vitacolonna, Matteo D’Angelo, Giulia Pavone, Peter A Mattei, Marco Liberati, Claudio Celentano J Matern Fetal Neonatal Med. 2013 Jul;26(10):967-72.
(10) Ovulatory and metabolic effects of D-chiro-inositol in the polycystic ovary syndrome, J E Nestler, D J Jakubowicz, P Reamer, R D Gunn, G Allan, N Engl J Med. 1999 Apr 29;340(17):1314-20.
(11) Long-term Metformin Use and Vitamin B12 Deficiency in the Diabetes Prevention Program Outcomes Study, Vanita R Aroda, Sharon L Edelstein, Ronald B Goldberg, William C Knowler, Santica M Marcovina, Trevor J Orchard, George A Bray… J Clin Endocrinol Metab. 2016 Apr;101(4):1754-61.