Low GI Diet for PCOS

Chunks of cooked sweet potatoes.

The most common endocrine disorder diagnosed in women is PCOS, or polycystic ovary syndrome. This condition is characterized by an hormonal imbalance, which can cause an irregular menstrual cycle, weight gain or the inability to lose weight, acne, hair growth on the face, multiple cysts on the ovaries, depression and infertility. Fortunately, women with PCOS can alleviate most of their symptoms by making dietary changes.

Underlying Problem

Although the exact cause triggering the development of PCOS is still unknown, most experts agree that insulin resistance seems to be a common feature of this condition, as explained by dietitian Martha McKittrick. Insulin is a hormone released by the pancreas in response to the consumption of carbohydrates or sugar. The role of insulin is to maintain normal blood sugar levels, getting rid of the sugar consumed by moving it into the cells, where it is either used for energy or stored as glycogen or fat. However, women with PCOS appear to have higher levels of circulating insulin in their body, which is called hyperinsulinemia. In this condition, the pancreas tries to produce more and more insulin because the cells do not respond normally to its action.


Glycemic Index

The glycemic index, or GI, constitutes the best tool available to classify carbohydrate-rich foods according to their ability to elevate blood sugar levels after consumption. High-GI foods -- those having a GI above 70 -- will raise blood sugar levels rapidly and trigger a large release of insulin at the same time, while low GI foods, with a GI below 55, will produce a slow rise in blood sugar levels, which is associated with a smaller release of insulin from the pancreas. Only carbohydrate-containing foods can have a GI, because it is impossible to measure the GI of foods high in fat, such as oil or butter, foods high in protein, such as meat and eggs, or foods that do not contain a sufficient amount of carbohydrates, such as broccoli or lettuce.


Low GI Diet and Insulin Resistance

Diets rich in foods with a lower GI can be especially helpful for women with PCOS. By causing a slower rise in blood sugar levels, these foods tend to lead to lower levels of insulin. McKittrick recommends the consumption of more low GI and high-fiber carbohydrates. A study comparing the impact of a low GI diet in overweight, premenopausal women with PCOS against a macronutrient-matched healthy diet assessed the participating women after a year or after they had achieved a weight loss corresponding to 7 percent of their body weight. Researchers found that women in the low GI diet group had significantly greater improvements in their insulin sensitivity, and 95 percent of them also benefited from an improved menstrual cycle compared to 63 percent in the control group, as reported in the July 2010 issue of the "American Journal of Clinical Nutrition."


Low GI Foods

If you decide to adopt a low GI diet to better manage your PCOS, first eliminate high GI carbohydrates, such as regular potatoes -- mashed, baked, boiled or fried -- processed breakfast cereals, white or whole grain bread, white rice, jelly beans and dates. Instead of a white potato, opt for small amounts of sweet potatoes. Have old-fashioned oat flakes or steel-cut oats for breakfast, and use sourdough or stone-ground whole-grain bread for sandwiches. Accompany your meal with barley, quinoa or basmati rice instead of traditional white rice. Replacing high GI carbohydrates will help you lower the GI of your diet and improve your PCOS-associated symptoms.