I have it. It causes insulin resistant, so you get more cravings, wich can cause weight gain and it makes weight loss a little bit more difficult. BUT it  doesn't make you obese. In fact, weight loss is advised as treatment. When I found out I had it my bmi was 23, since then I've been more careful about those cravings and I got a gym membership. My bmi is 19 now, and my PCOS got way less problematic.