The Gut Microbiome and PCOS (Polycystic Ovary Syndrome)

Comment from Genesis Trustee and leading PCOS expert, Professor Stephen Franks, following publication of The Gut Microbiome in Polycystic Ovary Syndrome and Its Association with Metabolic Traits (Lüll et al.).

There has been a lot of interest recently in the microbiome and in particular the gut microbiome, which is to say the population of billions of bacteria that normally (and mostly healthily) colonise our gut. Studies over the last few years have shown that there is a relationship between the food you eat, the microbiome of your gut and metabolic health.

Not surprisingly there have been a few recent studies in women with polycystic ovary syndrome. This latest one1 I think illustrates an important point about the relationship between PCOS and body weight. This was a truly international, collaborative study between universities in Finland, Estonia, Spain, Poland, Canada and Imperial College in the UK.

The results from this large study show that, yes, the microbiome in women with polycystic ovary syndrome is different from that seen in a control population but once you take body weight into account there is very little difference between the groups. So as with many health issues in women with polycystic ovary syndrome, the key factor is the interaction between PCOS and body weight; if your body mass index is near to, or within the normal range, your chances of having metabolic abnormalities (for example prediabetes or type 2 diabetes) are much closer to that in the general population than if you are overweight or obese. That doesn’t mean that women who are overweight or obese cannot do anything about it. Far from it; even a reduction in weight of 5kg (11lb) can make a big difference to your gut microbiome, to your blood sugar levels and to your general metabolic health.


  1. The Gut Microbiome in Polycystic Ovary Syndrome and Its Association with Metabolic Traits (Journal of Clinical Endocrinology and Metabolism, K Lüll, R Arffman, A Sola-Leyva, N Molina, O Aasmets, K Herzig, J Plaza-Díaz, S Franks, L Morin-Papunen, J Tapanainen, A Salumets, S Altmäe, T Piltonen, E Org)