PCOS & Supplements Commonly Recommended

Like many chronic conditions, PCOS is not immune to the promotion of supplements – especially by non-regulated providers and influencers.

Polycystic ovarian syndrome (PCOS) is a metabolic condition that impacts the development and maturation of ovum, impacting the regularity of menstrual cycles. It is accompanied by “cysts” on the ovary (these are immature follicles, not fluid-filled cysts) and high androgens such as DHEA-s and testosterone. There can be a few contributing states to PCOS, such as insulin resistance, chronic inflammation, and adrenal overproduction of cortisol. It also increases the risk of other non-gynaecological conditions such as diabetes and heart disease.

While many supplements are suggested for PCOS, there are several that are more common and have been through studies to determine how effective they are!

1. Vitamin D – this fat-soluble vitamin is involved in bone health and immune system functioning. It’s also thought to be involved in glycemic control. In countries such as Canada, where sunlight isn’t accessible all year round, deficiency might be a risk.

With regards to PCOS, it’s often been associated with improvements in insulin resistance, ovarian reserve and menstrual regularity. However, results are inconsistent and studies have quite a few important limitations, like small samples, poor randomization, and even dosing of vitamin D (1).

2. Inositol – this is a carbocyclic sugar rich in the brain and other tissues, such as the ovary! There are several types, including myo-inositol and D-chiro-inositol. It’s very commonly suggested as it may play a role in blood sugar management. Here’s the catch: D-chiro-inositol can act as an aromatase inhibitor, contributing to higher circulating levels of androgens such as testosterone, which are often already elevated in PCOS. High doses of the D-chiro type are common in many supplements on the market, so it’s important to be cautious.

Myo-inositol works at the levels of the brain and ovary for glucose uptake and FSH signalling, and a higher ratio favouring myo-inositol has a much greater advantage for individuals. It seems that supplements combined with other nutrients appear to be redundant and unnecessary (2).

3. NAC – this supplement is often compared with metformin for its function in blood sugar regulation and ovulatory support. Systematic review shows that supplementation reduces BMI (which we know is not an accurate marker of health or successful treatment) and total testosterone, but did not create a significant difference in pregnancy rate, serum LH level, fasting insulin or LH/FSH ratio.

It may be considered an alternative to metformin but we need more studies to assess if this is effective and safe – and as always, chat through with your provider about which fits you the best (3).

4. Berberine – this herb is thought to reduce insulin resistance, lower blood lipids and restore ovulation. In combination with metformin, studies show it may reduce total testosterone, BMI, and insulin resistance (identified by HOMA-IR). When taken independently, it may improve lipid levels therefore contributing to a lower risk of heart disease in PCOS. There are some GI side effects with taking so be cautious (4).

5. Spearmint or peppermint – these two are commonly suggested as teas for their antioxidant levels and potential benefits on glycemic control, menstrual regulation and pregnancy rate. Studies have shown a decrease in testosterone levels and increase in LH and FSH levels at 2 cups per day. They may also reduce triglycerides and increase estrogen when taking in the follicular phase – this might be an advantage for those with low levels (5).

6. Peony (Paeonia lactiflora) – this herb is commonly suggested for regulating the menstrual cycle and often in combination with other herbal products. In studies, it has shown reductions in free and total testosterone in combination with Chinese liquorice (glycyrrhiza uralensis), however these were small samples so were unfortunately not statistically significant results.

NOTE: When something isn’t statistically significant, that doesn’t always mean it’s not clinically significant (important to the patient) – a patient needs to review their goals with their provider.

When it was combined with Chinese cinnamon (cinnamomum cassia) there were reductions of LH and increased estradiol – this can be relevant in “hyper-functioning oligomenorrhea and amenorrhea” where the ovaries are trying really hard to ovulate without success (6).

7. Vitex (Vitex agnus-castus) - this herb is a frequent flyer in the PCOS world, commonly recommended to “regulate” the menstrual cycle. It’s thought to act like hormones in the body, and is often suggested in a cyclical fashion like birth control. In studies, it appears to lower prolactin by binding to dopamine receptors and lower secretion.

Menstrual regularity was also improved with an increased average number of luteal days – this can be positive if a person is struggling with a long enough luteal phase for progesterone exposure and pregnancy success (6).

Like any supplement recommendation, it’s important to make sure you ask your provider about all the risks, benefits and alternative options available to you. Be safe out there!

References:

1. Voulgaris, N., Papanastasiou, L., Piaditis, G., Angelousi, A., Kaltsas, G., Mastorakos, G., & Kassi, E. (2017). Vitamin D and aspects of female fertility. Hormones (Athens, Greece), 16(1), 5–21. https://doi.org/10.14310/horm.2002.1715.

2. Roseff, S., & Montenegro, M. (2020). Inositol Treatment for PCOS Should Be Science-Based and Not Arbitrary. International journal of endocrinology, 2020, 6461254. https://doi.org/10.1155/2020/6461254.

3. Song, Y., Wang, H., Huang, H., & Zhu, Z. (2020). Comparison of the efficacy between NAC and metformin in treating PCOS patients: a meta-analysis. Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, 36(3), 204–210. https://doi.org/10.1080/09513590.2019.1689553.

4. Zhao, H., Xing, C., Zhang, J., & He, B. (2021). Comparative efficacy of oral insulin sensitizers metformin, thiazolidinediones, inositol, and berberine in improving endocrine and metabolic profiles in women with PCOS: a network meta-analysis. Reproductive health, 18(1), 171. https://doi.org/10.1186/s12978-021-01207-7.

5. Ashkar, F., Rezaei, S., Salahshoornezhad, S., Vahid, F., Gholamalizadeh, M., Dahka, S. M., & Doaei, S. (2020). The Role of medicinal herbs in treatment of insulin resistance in patients with Polycystic Ovary Syndrome: A literature review. Biomolecular concepts, 11(1), 57–75. https://doi.org/10.1515/bmc-2020-0005.

6. Arentz, S., Abbott, J. A., Smith, C. A., & Bensoussan, A. (2014). Herbal medicine for the management of polycystic ovary syndrome (PCOS) and associated oligo/amenorrhoea and hyperandrogenism; a review of the laboratory evidence for effects with corroborative clinical findings. BMC complementary and alternative medicine, 14, 511. https://doi.org/10.1186/1472-6882-14-511.