PCOS Nutrition Myths (and What Actually Helps)

Polycystic Ovary Syndrome (PCOS) affects around one in ten women in the UK and is a leading cause of irregular periods, fertility challenges and unwanted symptoms like acne, weight gain and excess hair growth. It is a complex hormonal condition. However, nutrition and lifestyle can play a powerful role in supporting your health and reducing symptoms.

Unfortunately, there is a lot of misinformation online. In this post, we take a closer look at some of the most common myths about PCOS and nutrition, and what the science actually says.

Myth 1: You need to cut out all carbohydrates

One of the most common misconceptions is that carbohydrates are the enemy when managing PCOS. While it is true that insulin resistance is common in PCOS, completely cutting out carbohydrates is not necessary – and for many people, it can be counterproductive.

Overly restricting carbohydrates can affect energy levels, disrupt hormone production, and lead to binge eating or an unhealthy relationship with food. In fact, some studies suggest that moderate carbohydrate intake from whole food sources can help manage blood sugar and insulin levels more effectively than extreme restriction.

What helps: Focus on complex, fibre-rich carbohydrates such as whole oats, sweet potato, lentils, brown rice and quinoa. These break down more slowly and help to maintain steady blood sugar levels. Pairing carbohydrates with protein and healthy fats – for example, hummus with oatcakes, or brown rice with salmon and avocado – further reduces glucose spikes.

Myth 2: Dairy makes PCOS worse for everyone

Some influencers recommend cutting out dairy entirely to improve PCOS symptoms, particularly acne and inflammation. However, the evidence is mixed, and this advice is not always necessary.

Some studies have found that high intake of low-fat dairy products might increase insulin levels and androgens (male hormones), which could aggravate symptoms in certain people. However, other research shows that fermented, full-fat dairy like kefir, Greek yoghurt and cheese may have a beneficial effect on gut health and inflammation. For example, a 2020 study in the Journal of Functional Foods found that fermented dairy may reduce markers of inflammation, and other research supports its role in a balanced gut microbiome.

What helps: Incorporate fermented dairy such as Greek yoghurt and kefir milk. If you are dairy-free or vegan opt for plant-based alternatives such as coconut kefir or soya yoghurt.

Myth 3: Gluten is bad for everyone with PCOS

Going gluten-free has become trendy, and some claim it can help manage PCOS. But unless you have coeliac disease or a diagnosed gluten sensitivity, there is no strong evidence that gluten is harmful in PCOS. In fact, many gluten-free substitutes are low in fibre and nutrients, and some are heavily processed. This can actually worsen insulin resistance or inflammation in the long term.

Rather than cutting out gluten altogether, focus on whole, minimally processed grains. If you find that gluten-containing foods cause bloating or fatigue, consider trying a temporary elimination under the guidance of a nutritionist.

Myth 4: You have to lose weight to manage symptoms

Many women are told to simply "lose weight" to manage PCOS. While weight loss can improve insulin sensitivity and hormone regulation, it is not a guaranteed solution, and it is not appropriate to make weight loss the only focus of care.

Weight gain in PCOS is often a symptom of underlying hormonal and metabolic issues. Focusing only on weight can worsen body image, mental health and even increase disordered eating behaviours. Importantly, people in all body sizes can have PCOS and still benefit from targeted nutrition support.

Focus on improving energy, reducing inflammation, supporting your cycle and stabilising blood sugar. Sustainable improvements in wellbeing often lead to positive shifts in weight or body composition over time, without extreme measures.

Myth 5: Supplements can fix everything

There is growing interest in supplements for PCOS, from inositol and NAC to berberine and zinc.

Inositol, especially myo-inositol (MI), has the most robust clinical evidence. It acts as an insulin-sensitising agent and has been shown to support ovulation and reduce androgens in many women with PCOS. A 2017 meta-analysis in Obstetrics & Gynecology Science reviewed 9 randomised controlled trials and found that myo-inositol significantly reduced fasting insulin, improved insulin resistance (HOMA-IR), and reduced androgen levels in women with PCOS. A more recent 2023 systematic review and meta-analysis in Reproductive Biology and Endocrinology evaluated 26 trials with over 1,600 women. It concluded that inositol improved menstrual regularity, insulin sensitivity, BMI, and testosterone levels, with fewer side effects than metformin.

Other supplements such as omega-3 fatty acids, NAC (N-acetylcysteine), and vitamin D also show promise, but the evidence is not as strong or consistent as for inositol.

Not all supplements work for everyone, and some can interact with medications or have side effects. Use supplements strategically, with guidance from a Registered Nutritionist.

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Final Thoughts

PCOS is a complex condition, and nutrition can have a big impact. However, there is no one-size-fits-all solution. If you are unsure where to start, or if you feel like you’ve tried everything, working with a nutrition professional can help you create a plan that works with your body. I offer one-to-one consultations to help you understand your symptoms, build a sustainable food strategy and feel better in your body. Feel free to get in touch if you'd like to discuss working together.

References

1. Unfer, V., Facchinetti, F., Orrù, B., Carlomagno, G., & Nestler, J. E. (2017). Myo-inositol effects in women with PCOS: A meta-analysis of randomised controlled trials. Obstetrics & Gynecology Science, 60(4), 336–344. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5655679/

2. Laganà, A. S., Vitale, S. G., Sapia, F., Valenti, G., Corrado, F., Padula, F., Rapisarda, A. M., & D’Anna, R. (2023). Inositols in PCOS: Systematic review and meta-analysis. Reproductive Biology and Endocrinology, 21(1), Article 9. https://rbej.biomedcentral.com/articles/10.1186/s12958-023-01055-z

3. Fruzzetti, F., Perini, D., & Fidecicchi, T. (2024). Myo-inositol with or without D-chiro-inositol vs. metformin in PCOS management: A randomised controlled trial. Reproductive Health. https://pubmed.ncbi.nlm.nih.gov/37265016/

4. Barrea, L., Muscogiuri, G., Pugliese, G., de Alteriis, G., Colao, A., & Savastano, S. (2020). Fermented dairy products and inflammation in metabolic syndrome and PCOS: A functional food strategy? Journal of Functional Foods, 67, 103861. https://doi.org/10.1016/j.jff.2020.103861

5. Toscani, A., et al. (2002). Coeliac disease and polycystic ovary syndrome: No significant association. International Journal of Gynecology & Obstetrics, 77(3), 267–268. https://doi.org/10.1016/S0020-7292(02)00039-8

6. Lim, S. S., Davies, M. J., Norman, R. J., & Moran, L. J. (2019). Dietary interventions in PCOS: A systematic review and meta-analysis. Human Reproduction Update, 25(2), 160–177. https://doi.org/10.1093/humupd/dmy045