Diet is important in a patient with PCOS to help control the condition. Obsesity in PCOS is very common due to insulin resistance ie the levels of insulin in the body are high. This happens because there is a defect in getting the blood sugar into the cells so the pancreas secretes more and more insulin. It has been shown that just reducing weight by 5% can help improve the condition. Periods go back to being regular and insulin levels decrease, skin improves. The problem is that it is difficult to lose weight in PCOS. The normal diet of low fat high carbohydrate diets dont work because the refined carbohydrates are quickly turned to sugar in the blood, and this in turn raises the insulin level even higher. The ideal would be a low carbohydrate high protein diet, combined with aerobic excercises. Some carbohydrate should be consumed to prevent ketosis. Complex carbohydrates such as whole meal bread and brown rice should be taken in small amounts. Low glycaemic foods should be part of the diet so as not to allow spikes of blood sugar. So diet and excercise are the first line of treatment for PCOS especially when associated with obesity.