PCOS (polycystic ovaries): what to eat and what to avoid

Why food matters so much in PCOS

PCOS is a hormonal disorder with three possible features: irregular or absent cycles, signs of high androgens (acne, hair growth) and polycystic-looking ovaries. Behind it, in the vast majority of cases, there is a common denominator: insulin resistance, meaning the body needs to produce more insulin than normal to handle blood sugar. Excess insulin worsens the hormonal imbalance. And here is the good news: what you eat directly influences insulin, so nutrition is one of the most powerful levers you have — even if you are lean.

What to prioritise on the plate

There is no single "PCOS diet", but the evidence consistently points to a low-glycaemic-index pattern, close to the Mediterranean. These are the pillars:

• Protein at every meal (eggs, fish, lean meat, legumes, tofu, dairy): satiates and stabilises glucose.
• Low-glycaemic-index carbs: legumes, oats, quinoa, wholegrain bread and pasta, whole fruit.
• Plenty of fibre and vegetables: half a plate of vegetables improves insulin sensitivity.
• Healthy fats: extra virgin olive oil, oily fish, avocado, nuts.
• Anti-inflammatory foods: oily fish, berries, leafy greens, spices like turmeric.

What to reduce

More than banning, it is about them no longer being the base of your day: added sugars and soft drinks, pastries and sweets, refined flours (white bread, white pasta, too much white rice) and ultra-processed foods. These spike glucose and insulin, exactly the opposite of what PCOS needs. Swapping them for their wholegrain versions and for real food is probably the highest-impact change.

Weight, exercise and insulin

When there is excess weight, losing 5-10% usually has a disproportionately good effect: many women regain regular cycles and improve their markers. But PCOS also affects lean women, so the goal is not always to lose weight — sometimes it is only to improve diet quality and insulin sensitivity. In both cases exercise helps on its own: strength training in particular improves glucose uptake by the muscle independently of diet.

Before changing anything

PCOS is a medical and very individual diagnosis: there are different profiles, there may be other factors (thyroid, prolactin) and sometimes medication or supplements like inositol are needed, which must be prescribed by a professional. Use this guide to understand the logic of nutrition, but accompany the changes with your gynaecologist, endocrinologist or a specialised dietitian. Food is a huge lever, but it is part of a broader plan.