Reviewed by Dr Anita Wąsik, PhD, DipHM
Biomedical Scientist and Medical Herbalist
Published 04/10/2023
Polycystic Ovary Syndrome (PCOS) is a common hormonal disorder affecting 8-15% of women during their reproductive years, or approximately 294 million women globally.
Although the exact cause of PCOS is widely undecided, many experts have linked insulin resistance to the disorder. Also believed to play a role are chronic inflammation, androgen and oestrogen excess, gut microbiome dysregulation, and genetics.
Sadly, as many as 70% of women with PCOS go undiagnosed, and consequently, untreated for their symptoms which can include irregular menstrual cycles, ovarian cysts, infertility, weight gain, mood swings and excess hair growth.
For those women who are diagnosed, traditional PCOS treatments like birth control pills and metformin can come with unwelcome side effects, leading many to seek natural solutions.
One of the supplements gaining attention in the management of PCOS is inositol, particularly myo & d-chiro inositol.
At a Glance
In this article, we’ll unlock the latest studies which show myo & d-chiro inositol’s potential to:
- Restore menstrual regularity
- Shorten cycle length by half
- Improve insulin sensitivity and glucose metabolism
- Improve weight loss and BMI
- Reduce unwanted hair growth
- Increase fertility
A Root Cause—Insulin Resistance
Most women with PCOS, regardless of weight, struggle with insulin resistance. It’s thought to be the primary driver of PCOS in up to 80% of cases.
In fact, insulin resistance is so common in women with PCOS that some experts suggest renaming PCOS to reflect its metabolic nature.
So, what is insulin resistance? Insulin resistance means cells throughout the body are less responsive to the hormone insulin. To compensate, the body pumps out more insulin, messing with blood sugar levels and exacerbating hormonal imbalance.
What is Inositol?
Inositol is a natural compound found in foods like citrus fruits, cantaloupe melon, beans, grains, and nuts.
While it plays several vital roles in our body, from aiding nerve function to assisting with fat metabolism, it has recently gained attention for its potential benefits in conditions like PCOS.
Interestingly, studies have shown that women with PCOS tend to have lower levels of inositol in their system.
Inositol and Insulin Sensitivity
For women with PCOS, introducing myo & d-chiro-inositol has been shown to significantly enhance insulin sensitivity and glucose metabolism.
By improving cellular sensitivity to insulin, inositol helps restore metabolic equilibrium, linked with improved weight control and hormonal balance.
Inositol’s Effects on Hormonal Levels
Multiple studies reveal inositol’s potential in restoring the body's hormonal equilibrium by influencing several key hormones that are commonly out of balance in PCOS:
Inositol’s Effect on Androgens
Elevated testosterone is a hallmark of PCOS causing frustrating symptoms like hirsutism, acne, unwanted hair growth and even hair loss. Inositol's potential to reduce testosterone level addresses not only the hormonal imbalance but also its distressing manifestations.
Inositol’s Effect on LH and FSH balance
One of the significant hormonal imbalances in PCOS patients is an elevated LH in relation to FSH. Inositol has shown promise in reducing elevated LH levels and bringing the LH:FSH ratio closer to normal.
Inositol’s Effect on Progesterone and Oestrogen
By promoting regular ovulation, inositol may help to bring progesterone and oestrogen levels into balance.
Can Inositol Bring Back Periods?
Many women with PCOS experience delayed ovulation or none at all. Without ovulation, the body might not release the necessary hormones for a regular menstrual cycle, resulting in absent (amenorrhea) or irregular periods.
Inositol’s influence on androgen levels improves ovulation rates, leading to a more consistent menstrual cycle.
Several studies over the past few years have put inositol to the test. Here's what they found:
Inositol and Menstrual Regularity
A 2015 study of 47 women with PCOS found that those treated with d-chiro-inositol saw a significant increase in menstrual cycle regularity. Improved markers linked to better egg quality (such as AMH) and reduced insulin resistance.
Inositol and Cycle Length
Fast forward to 2021, and Kachhawa et al. investigated the effects of a combination of myo-inositol and d-chiro-inositol on 70 young women (aged 15-24 years) with PCOS and irregular cycles. The outcome? Eighty five percent experienced the return of regular cycles, whilst the average cycle length was halved.
Inositol and Amenorrhea
A 2008 study by Genazzani et al. on 20 overweight PCOS patients with irregular or absent cycles found that 12 weeks of myo-inositol supplementation restored cycle regularity in all of the women.
Can Inositol Support Fertility?
When it comes to fertility, the results of inositol supplementation are promising for women with PCOS, especially in a 40:1 ratio.
Multiple studies demonstrate myo-inositol improves ovulation, egg quality, and pregnancy rates without adverse effects at doses up to 4g per day.
An analysis of 12 clinical trials found that myo & d-chiro-inositol in a 40:1 ratio contributed to improved oocyte follicular development and maturation, enhancing outcomes in IVF procedures and overall fertility.
Interestingly, in one study comparing inositol to metformin, it was found that the women who supplemented with a combination of myo & d-chiro-inositol had 3-4 times better ovulation and pregnancy rates than those who supplemented with metformin (46.7% vs. 13.6%), and significantly better results in weight reduction.
The number of studies is still small, but early evidence is promising for inositol making a difference in PCOS fertility.
Inositol Dosing for PCOS
For managing PCOS, the most effective dosage seems to be 2g of myo & d-chiro-inositol taken twice per day in the optimal 40:1 ratio.
However, increasing the d-chiro-inositol ratio to levels above 40:1 has been noted to diminish the reproductive benefits, and even worsen symptoms.
Inositol and PCOS Recap
A growing body of research underscores the potential benefits of myo-inositol & d-chiro-inositol supplementation for PCOS, particularly in its optimal 40:1 ratio, on cycle regularity, fertility and weight loss.
With no adverse side effects at doses of up to 4g per day.
While not a standalone cure, it could be an excellent complement to lifestyle changes including a PCOS-friendly diet, exercise, and stress reduction, especially for women seeking a natural approach to hormonal equilibrium.
Disclaimer
As always, before diving into any new supplement or treatment, it's essential to consult a healthcare professional to determine the best path forward.
Article Bios
PhD, DipHM, Biomedical Scientist and Medical Herbalist
Dr. Anita Wąsik, PhD, DipHM is a renowned Biomedical Scientist and Medical Herbalist, with deep roots in both academic research and herbal medicine practice. Boasting a rigorous academic background, she holds a PhD from the University of Helsinki's Faculty of Medicine and a MSc in Biotechnology and Molecular Biology from the University of Wroclaw. Anita's expansive herbal medicine clinical experience, notably intensive training at Heartwood Education accredited by the distinguished National Institute of Medical Herbalists (NIMH), positions her as a leading authority in the realm of holistic health and women's well-being. Anita seamlessly integrates millennia-old healing traditions with cutting-edge scientific research. Her commitment to the cause is further reflected through her affiliations with the Finnish Association of Natural Medicine and Finnish Phytotherapy Association.
Disclaimer: While Anita's expertise fortifies the credibility and accuracy of Bossology's content on female health, it's pivotal to highlight her unbiased perspective: she has no monetary ties to Bossology's product sales. This underlines her primary commitment to objective, evidence-based advice, and the holistic well-being of women everywhere.
For a deeper dive into her professional journey and credentials, connect with Anita on her website.
Founder of Bossology™
Jasmin's story is a personal one. After struggling with unresolved PCOS for 11 years, including irregular or absent periods, mood instability, and yo-yo dieting, she found herself in a state of high stress and at war with her own body. It was only when she uncovered the link between her hormone imbalance and insulin resistance that everything changed. Through this new understanding of her body and the power of plants, her cycles returned, her weight stabilized naturally, she was able to control cravings, and most importantly, her mood and anxiety lifted, resulting in newfound confidence and energy to focus on what mattered most. Now on a mission, Bossology™ aims to unlock the science that will empower more women to take control through the power of plants, adopting preventative and natural solutions over fairytale supplements or band-aids that mask symptoms. You can connect with Jasmin by emailing info@bossology.me.
16 Sources ↓
- Bossology draws from peer-reviewed studies and academic research institutions, with an aim to provide accurate and up to date information.
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