PCOS affects 1 in 10 women, yet it's still widely misunderstood, especially when it comes to the role our diet can play. Nutritionist Ro Huntriss explains.

Polycystic ovary syndrome (PCOS) is the most common hormonal disorder in women of reproductive age, affecting 1 in 10 women within this age group in the UK [1]. PCOS is characterized by an imbalance of reproductive hormones which can cause irregular periods, high levels of androgens - or male hormones - and polycystic ovaries.

PCOS is a leading cause of menstrual irregularity and female infertility, and it can pose a barrier to successful weight loss due to the insulin resistance it presents.

The condition was first described in 1935, and the understanding and identification of the condition continues to improve. Healthcare professionals are becoming more proficient in recognizing the signs of PCOS, diagnosing the condition and helping patients to manage it, while awareness from a patient perspective is also growing.

In addition to the increase in PCOS communities, support groups, charities and online resources, many celebrities such as Victoria Beckham, Jillian Michaels, Harnaam Kaur, Lea Michele, Jaime King have opened up about their struggles with PCOS.

But how exactly does PCOS work? What is its relationship with diet? And what can be done to manage the condition?

What is PCOS?

Let’s first take a moment to discuss the name. ‘Poly’ means ‘many’ suggesting there would be many cysts on a woman’s ovaries, but technically the ‘cysts’ are simply fluid filled sacs or follicles which are structures which normally would contain an immature egg that would mature and be released during ovulation.

However in PCOS, high levels of androgens can lead to the growth of multiple follicles that may not develop properly or release an egg during ovulation. Therefore, managing levels of androgens is a key part of the management strategy in PCOS as normal levels can help to restore menstrual regularity and reduce symptoms associated with hyperandrogenism.

Insulin resistance

We know that PCOS is one of the most common reproductive conditions seen in women, but it is also a metabolic disorder too. A key feature of PCOS is insulin resistance whereby a woman’s cells are less responsive to insulin - the hormone that regulates blood sugar (glucose). Insulin resistance leads to higher levels of insulin in the blood which impacts other metabolic processes and hormones too.

Excess insulin promotes fat storage, can increase hunger, impair appetite-regulating hormones and contributes to inflammation which can lead to difficulty in managing weight [2], a common struggle for those living with the condition.

PCOS without polycystic ovaries

According to the NHS[3], two of the three main features of PCOS are required for a diagnosis. These are: irregular periods meaning that women do not release eggs or ovulate regularly, high levels of androgens (male hormones) which can present as excess facial hair or thinning hair on the head, and polycystic ovaries.

You can have PCOS without having polycystic ovaries though. If you have irregular periods and high levels of androgens, you can still get diagnosed with the condition - despite the name being an inaccurate description of your presentation.

Although the exact cause of PCOS is unknown, it is believed that several factors including genetics and environmental factors such as obesity, insulin resistance and fetal androgen exposure may play a role [4]. There is no cure for PCOS, but lifestyle changes can be very effective in managing symptoms with medication and less commonly surgery being other treatment options.

What are the signs you might have PCOS?

Signs and symptoms of PCOS usually become apparent during late puberty or early 20s and include [3]:

• Irregular periods.
• Fertility issues.
• Excessive hair growth (hirsutism) – usually on the face, chest, back or buttocks.
• Difficulty managing weight.
• Thinning hair/ hair loss.
• Oily skin/ acne.
• Insulin resistance.

PCOS is also associated with an increased risk of developing health issues later in life such as depression, metabolic syndrome (type 2 diabetes, high blood pressure and obesity) and endometrial cancer [4].

If you suffer from any of these symptoms and suspect you may have PCOS, book an appointment with your doctor to discuss. A diagnosis is the first step towards successful management of the condition and its symptoms.

How can diet influence PCOS?

The best diet for PCOS has not been determined. However, the evidence shows that many different dietary approaches can help to support the management of PCOS and reduce the severity of symptoms it is associated with. Dietary patterns associated with improved PCOS management include the following:

• A low-carbohydrate Mediterranean style diet was shown to be a favorable treatment over a low-fat diet in supporting people living with PCOS, significantly restoring menstrual cycles, improving anthropometry and correcting hormone levels[5]
• A paper by Saadati et al. (2021) shared that a low glycemic index diet may play a significant role in reducing the risk and improving symptoms of PCOS; but the authors agree that there is insufficient evidence for choosing the best diet for the management of the condition[6].
• High fiber which could potentially alleviate inflammation, improve reproductive function, and support gut health [7].
• The DASH diet (rich in fruits, vegetables, whole grains, low-fat dairy products and low in saturated fats, cholesterol, refined grains, sodium, and sugar) which may improve weight loss, BMI, abdominal fat mass, reduce levels of androgens, improve insulin resistance and markers of inflammation [8][9].
• A higher protein intake - replacing carbohydrate with protein - may improve weight loss and glucose metabolism [10].
• Anti-inflammatory diet (rich in fish, legumes, fiber and lower in calories, meat and added sugars) may improve in body composition, hormone levels, menstrual cycle regularity, blood glucose control and inflammatory markers [11].
• Cinnamon is also suggested to improve insulin sensitivity and decreased glucose levels in those with PCOS so can be a useful addition to one’s diet[12].

A 2021 systematic review and meta-analysis[13] (considered the highest level of evidence) on the topic suggested that low-carbohydrate diets did appear superior in optimizing reproductive outcomes and calorie reduction (and therefore weight loss) was critical in managing high androgen levels. However, caution should be applied when interpreting such headlines. A true low-carbohydrate diet is considered to be <26% energy coming from carbohydrates or below 130g carbohydrate per day.

Many of the studies labeled as low-carbohydrate were technically moderate-carbohydrate (26-45% energy intake from carbohydrates) as opposed to low, a common reporting theme seen in such papers. Therefore a more reasonable conclusion may be that the avoidance of a high-carbohydrate diet (>45% energy from carbohydrates) is likely to be of benefit to people living with PCOS. The benefit may also be heightened due to the lower-carbohydrate diets being accompanied with a high protein intake as highlighted above.

The authors did note that dynamic dietary advice should be offered to all PCOS patients, but should be considered in the context of the patient’s own circumstances, personal needs and expectations.

Supplementing for PCOS

Supplements can also play an influential role in the management of PCOS.

• Awareness of the supplement inositol is growing, supported by a strong evidence-base to support its use in women with PCOS. A 2023 review on the topic[14] concluded that women treated with inositol were 1.8 times more likely to have a regular menstrual cycle. Inositols were also associated with improved BMI, testosterone and insulin levels.
• Vitamin D plays an important role in general and reproductive health. Did you know that Vitamin D receptors are also found in the ovaries? Vitamin D deficiency can be common in women with PCOS. Supplementation of Vitamin D may lead to an improvement in insulin sensitivity and reduction in androgen levels[15].
• PCOS is considered a pro-inflammatory state. Omega-3 is a potent anti-inflammatory agent and has been associated with reduced levels of insulin resistance and improved metabolic markers in women with PCOS[16].
• N-acetyl-cysteine is a supplement form of cysteine, which is a semi-essential amino acid. Its use in PCOS has been shown to improve both ovulation and pregnancy rates[17], with the effect likely to be more profound in women with a higher BMI, higher levels of insulin resistance and oxidative stress[18].
• Even berberine has shown promise in reducing insulin resistance in women with PCOS[19].

These are just some of the supplements that are associated with improved PCOS management. If you want to add any supplements to your diet to support PCOS, it’s advisable to discuss this with a healthcare professional to ensure the right supplements can be chosen for and tailored to you.

Besides diet, what other lifestyle changes might improve symptoms of PCOS?

When we manage PCOS, it’s important to do so holistically. There are a few other things that we can pay attention to.

Weight management

Moderate weight loss (5% of body weight) has been associated with decreased circulating insulin and androgen hormones and improved symptoms such as menstrual regularity, ovulation, and fertility [20].

Physical activity

Daily activity, more vigorous exercise and resistance training can improve insulin sensitivity, lower levels of androgens and reduce stress [21][22].

Stress management

PCOS symptoms can cause stress, depression, and overall reduced quality of life (QOL). Therefore, stress reduction techniques like yoga, meditation, exercise or speaking to a therapist can help calm the mind and reduce depressive and anxiety symptoms [23].

Sleep

Poor sleep quality has been associated with an increased risk of obesity and insulin resistance, therefore sleep hygiene is an important lifestyle modification in managing PCOS symptoms [24].

Key takeaways

• PCOS is the most common hormonal and metabolic disorder of young women affecting 1 in 10 women of reproductive age in the UK, causing irregular periods, high levels of androgens (male hormones) and polycystic ovaries.
• PCOS can present differently in different people.
• Diet, supplements and positive lifestyle changes can have a significantly positive effect on PCOS and its associated symptoms.
• If you suspect you have PCOS, speak to your doctor who can support with a diagnosis.
• Work with a Registered Dietitian to understand the best dietary and supplement approaches for you.

References

1. Deswal, R. et al. (2020) The Prevalence of Polycystic Ovary Syndrome: A Brief Systematic Review. J Hum Reprod Sci, 13(4):261-271.
2. Szczuko, M. et al. (2021) Nutrition Strategy and Life Style in Polycystic Ovary Syndrome-Narrative Review. Nutrients, 18, 13(7), p. 2452.
3. NHS (2022) Overview: Polycystic ovary syndrome. Available at: https://www.nhs.uk/conditions/polycystic-ovary-syndrome-pcos/ (Accessed: 11 February 2023).
4. Rasquin Leon L.I., Anastasopoulou C. and Mayrin, J.V. (2022) Polycystic Ovarian Disease. StatPearls. Available at: https://www.ncbi.nlm.nih.gov/books/NBK459251/ (Accessed: 11 February 2023).
5. Mei, S., Ding, J., Wang, K., Ni, Z., & Yu, J. (2022). Mediterranean Diet Combined With a Low-Carbohydrate Dietary Pattern in the Treatment of Overweight Polycystic Ovary Syndrome Patients. Frontiers in nutrition, 9, 876620.
6. Saadati, N., Haidari, F., Barati, M., Nikbakht, R., Mirmomeni, G., & Rahim, F. (2021). The effect of low glycemic index diet on the reproductive and clinical profile in women with polycystic ovarian syndrome: A systematic review and meta-analysis. Heliyon, 7(11), e08338.
7. Wang, X. et al. (2022) High-Fiber Diet or Combined With Acarbose Alleviates Heterogeneous Phenotypes of Polycystic Ovary Syndrome by Regulating Gut Microbiota. Front Endocrinol (Lausanne). Available at: https://pubmed.ncbi.nlm.nih.gov/35185786/ (Accessed: 11 February 2023).
8. Asemi, Z. et and Esmaillzadeh, A. (2015). DASH diet, insulin resistance, and serum hs-CRP in polycystic ovary syndrome: a randomized controlled clinical trial. Horm Metab Res. 47(3), pp. 232-238.
9. Azadi-Yazdi, M. et al. (2017) Effects of Dietary Approach to Stop Hypertension diet on androgens, antioxidant status and body composition in overweight and obese women with polycystic ovary syndrome: a randomized controlled trial. J Hum Nutr Diet. 30(3), pp. 275-283.
10. Sørensen, L.B. (2012) Effects of increased dietary protein-to-carbohydrate ratios in women with polycystic ovary syndrome. Am J Clin Nutr. 95(1), pp. 39-48.
11. Salama, A.A. et al. (2015) Anti-Inflammatory Dietary Combo in Overweight and Obese Women with Polycystic Ovary Syndrome. N Am J Med Sci. 7(7), pp. 310-316.
12. Maleki, V., Faghfouri, A. H., Tabrizi, F. P. F., Moludi, J., Saleh-Ghadimi, S., Jafari-Vayghan, H., & Qaisar, S. A. (2021). Mechanistic and therapeutic insight into the effects of cinnamon in polycystic ovary syndrome: a systematic review. Journal of ovarian research, 14(1), 130.
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15. Morgante, G., Darino, I., Spanò, A., Luisi, S., Luddi, A., Piomboni, P., Governini, L., & De Leo, V. (2022). PCOS Physiopathology and Vitamin D Deficiency: Biological Insights and Perspectives for Treatment. Journal of clinical medicine, 11(15), 4509.
16. Yang K, Zeng L, Bao T, Ge J. Effectiveness of Omega-3 fatty acid for polycystic ovary syndrome: a systematic review and meta-analysis. Reprod Biol Endocrinol. 2018 Mar 27;16(1):27.
17. Thakker D, Raval A, Patel I, Walia R. N-acetylcysteine for polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled clinical trials. Obstet Gynecol Int. 2015;2015:817849.
18. Devi, N., Boya, C., Chhabra, M., & Bansal, D. (2020). N-acetyl-cysteine as adjuvant therapy in female infertility: a systematic review and meta-analysis. Journal of basic and clinical physiology and pharmacology, 32(5), 899–910.
19. Li, M. F., Zhou, X. M., & Li, X. L. (2018). The Effect of Berberine on Polycystic Ovary Syndrome Patients with Insulin Resistance (PCOS-IR): A Meta-Analysis and Systematic Review. Evidence-based complementary and alternative medicine : eCAM, 2018, 2532935.
20. Marzouk, T.M. et al. (2015) Effect of Dietary Weight Loss on Menstrual Regularity in Obese Young Adult Women with Polycystic Ovary Syndrome. J Pediatr Adolesc Gynecol.28(6), pp. 457-461.
21. Patten, R.K. et al. (2020) Exercise Interventions in Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis. Front Physiol. 7;11 p. 606.
22. Wright, P.J. et al. (2021) Resistance Training as Therapeutic Management in Women with PCOS: What is the Evidence? Int J Exerc Sci. 14(3), pp. 840-854.
23. Sidra, S. et al. (2019) Evaluation of clinical manifestations, health risks, and quality of life among women with polycystic ovary syndrome. Available at: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0223329 (Accessed: 11 February 2023).
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