Women with PCOS, or polycystic ovary syndrome, can see their symptoms improve by reducing their carbohydrate intake below 40 percent of their daily calories and ensuring that the carbohydrate foods they include in their diet have a low glycemic index -- below 55 -- as reported by dietitian Martha McKittrick. A lower-carb and low GI diet can help better manage insulin levels, which results in a more regular menstrual cycle, weight loss, if needed, and decreased insulin resistance, as reported in a study published in July 2010 in the "American Journal of Clinical Nutrition."
Because of potatoes' high carbohydrate content and high GI, women with PCOS should eliminate them from their diet. For example, a medium-size baked potato contains 36.6 g carbohydrates and 3.8 g fiber, which is the equivalent of 32.8 g of net carbs. Net carbs correspond to the amount of utilizable carbohydrates and can be calculated by removing the grams of dietary fiber from the grams of total carbohydrates. A baked potato with the skin has a glycemic index of 69, while the GI climbs to 98 if the potato is eaten without the skin. Mashed potatoes and french fries also should be avoided because they contain a lot of carbohydrates in addition to having a high GI.
A cup of white rice contains 44.5 g of carbohydrates and 0.6 g of fiber, which corresponds to 43.9 g of net carbs. Moreover, its GI varies between 72 and 89, making it a very high GI carbohydrate food. Skip white rice if you have PCOS.
Each slice of bread contains about 15.8 g of carbohydrates and 1.3 g of fiber on average, which corresponds to 14.5 g of net carbs per slice. Most people eat more than a slice at a time, which can bring their carb intake a lot higher. Whether bread is made with refined or whole grains, the net carbs are very similar. Moreover, most breads have a GI ranging between 70 and 72, which falls in the high GI zone, according to the University of Sydney.
Muffins have a moderate to high glycemic index, from between 52 and 69 depending on the recipe, but the reason they should be avoided by women with PCOS is their high carbohydrate content. For example, a commercially prepared blueberry muffin has 68.9 g of carbohydrates and 2.4 g of fiber, which is the equivalent of as much as 66.5 g of net carbs.
Many breakfast cereals are highly processed, making them a very bad choice for women with PCOS. However, cold cereals like corn flakes have a GI of about 80 and 1 cup provides 24.4 g of carbohydrates, 0.7 g of fiber and 23.7 g of net carbs. Puffed rice cereals also have a high GI, of approximately 82, in addition to containing 26.7 g of carbohydrates, 0.1 g of fiber and 26.6 g of net carbs per 1 cup serving. The University of Sydney recommends going for low GI cereals based on oat, barley or bran.
- PCOSupport: What is Polycystic Ovarian Syndrome (PCOS)?
- OBGYN.net: PCOS and Diet
- University of Sydney: The Glycemic Index
- USDA National Nutrient Database: Nutrient Data Laboratory
- "American Journal of Clinical Nutrition"; Effect of a low glycemic index compared with a conventional healthy diet on polycystic ovary syndrome; Kate A. Marsh et al; July 2010