Health
Eating with PCOS
No single diet has been shown to work best for PCOS, which the NHS now calls PMOS. What the international guideline recommends instead, and how to apply it.
What the evidence says
Polycystic ovary syndrome, which the NHS now calls polyendocrine metabolic ovarian syndrome (PMOS), is a hormone condition whose symptoms can include weight gain or difficulty losing weight. Low-carb, keto, low-GI, dairy-free and gluten-free diets are all promoted for it online.
The 2023 international evidence-based guideline reviewed the trials and concluded that there is no evidence to support any one type of diet composition over another for weight, metabolic, hormonal, reproductive or psychological outcomes. The evidence behind that statement is rated very low in certainty, so it may change, but no diet has earned a special claim.
What the guideline recommends instead
It advises sustainable healthy eating in line with general population guidelines, tailored to your preferences and goals, and warns against unduly restrictive or nutritionally unbalanced diets. In practice that means regular meals built on vegetables, fruit, wholegrains, pulses and protein foods you enjoy, in amounts that suit your energy needs.
The guideline stresses that a healthy lifestyle has benefits even without weight loss. For people with higher weight who choose to lose some, it suggests a tailored energy deficit and a lifelong focus on preventing further gain. A Cochrane review found that lifestyle programmes may modestly reduce weight and a measure of androgen levels, on low-quality evidence.
Activity and supplements
For activity, the guideline follows general advice for adults: 150–300 minutes of moderate activity a week, or 75–150 minutes of vigorous activity, plus muscle-strengthening on two non-consecutive days. It recommends exercise for everyone with the condition to improve metabolic health, whatever happens to weight.
Inositol is the most discussed supplement. The guideline says it could be considered because harm is limited, but that clinical benefits for ovulation, hair growth or weight are limited too, and that no specific type or dose can be recommended. It encourages telling your healthcare professional about any supplement you take.
Worth knowing
- This is general information and does not replace individual medical or dietetic advice. Food does not cure the condition: the NHS is clear that there is no cure, though treatments and lifestyle changes can help symptoms.
- If you take metformin or any other medicine, speak to your clinician before making large changes to how you eat, and do not stop or change medication because of a diet.
- If you are trying to conceive, or if dieting is affecting your mood or your relationship with food, ask your healthcare team for individual advice.
Common questions
Should I cut carbs or go keto for PCOS?
You can if it suits you, but the guideline found no diet composition better than another. A lower-carb pattern is one option among several; the one you can sustain matters most.
Do I need to avoid dairy or gluten?
The guideline found no evidence favouring any particular diet and warns against unduly restrictive ones. Unless you have coeliac disease or a diagnosed intolerance, there is no established reason to cut them out.
Will losing weight cure PCOS?
No, there is no cure. For people with higher weight, the guideline says weight management can bring significant clinical improvements, and that healthy habits have benefits even without weight loss.
Sources
- Recommendations from the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome, J Clin Endocrinol Metab
- Cochrane review: Lifestyle changes in women with polycystic ovary syndrome (2019)
- NHS: Polyendocrine metabolic ovarian syndrome (PMOS), formerly PCOS
General information, not medical or dietary advice. Speak to a doctor or registered dietitian about your own situation.