Have PCOS and Not losing weight? It could be your GI.

Do you have Polycystic Ovary Syndrome (PCOS) and are struggling to lose weight? You're not alone. As many as 80% of women with PCOS are overweight. The reason? High insulin levels, the central cause of PCOS. When insulin levels are high, it causes our bodies to store fat, usually in our bellies. Weight loss is difficult because it's hard to break down fat if your body is in fat storage mode. In order to lose weight, you have to lower your insulin levels. You can lower insulin by diet, exercise and insulin-lowering medications (metformin). If you have been taking insulin sensitizers and are exercising and watching your diet and still aren't seeing results it could be the types of foods you are eating.

The Evidence

A 2010 study compared a low glycemic (GI) index diet to a regular, healthy fiber diet in women with PCOS. Ninety-six women with PCOS were split into two groups: one group followed a low GI diet; another a high fiber diet that included whole grains. Both groups ate the same amount of calories and consumed the same distribution of macronutrients (50% carbohydrate, 23% protein, 27% fat, 34 grams fiber). The only difference was the glycemic index of foods. Results: The women with PCOS who followed the low GI diet showed a 3-fold greater improvement in insulin. Women who followed the low GI diet and took metformin showed the best improvements in insulin sensitivity.

Other studies have shown that individuals with high insulin levels do best as far as weight loss and improving insulin sensitivity on a low GI diet. A study published in the Journal of the American Medical Association in 2007 showed that individuals with high insulin lost significantly more weight (13 pounds vs. only 3 pounds) following a low GI diet than those with high insulin levels who followed a low fat diet.
Another great benefit: women with PCOS who followed the low GI diet also had more regular periods (95% compared with 63%).

These studies confirm that insulin secretion is an important factor in weight management. Individuals with high insulin levels can lose more weight and improve insulin and periods on a low GI diet.

What to know about the glycemic index diet.

The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating. Foods that fall under the high GI category cause surges in blood insulin soon after eating them. Foods categorized as medium GI cause mild changes and low GI foods cause the smallest increase in insulin.

Low GI foods 0-55
Medium GI foods 56-69
High GI foods 70 or more

Factors Influencing GI Ranking:

• Type of Starch
• Physical casing -intact grains have lower GI
• Fiber content -soluble fiber lowers the GI
• Sugar content -sugar increases GI
• Fat and protein content -slows GI
• Cooking methods-cooking soften foods, increasing starch content and GI
• Acid content-more acidic foods have lower GI
• Food processing-processed foods have higher GI

With this ranking, whole grain foods can be low, medium or even high GI versions. For example, All Bran has a GI value of 38 whereas the value of Cheerios is 74. See the GI value of your foods by viewing the complete GI data base: http://www.glycemicindex.com.

Tips on Eating Low GI

• Replace refined foods with low GI or whole foods (unprocessed, grain intact)
• Eat unprocessed breakfast cereals (bran, oats, barley)
• Replace white potatoes with sweet potatoes
• Avoid sugary foods and beverages
• Include protein and/or fat in meals and snacks (nuts are a great example)
• Cook pasta only until al dente (firm, not mushy)

Marsh K, et al. Effect of a low glycemic index compared with a conventional diet on polycystic ovary syndrome. Am J Clin Nutr 2010;92:83-92.

Ebbeling C, Leidig MM, Feldman HA, Lovesky MM, Ludwig DS. Effects of a low-glycemic load vs low-fat diet in obese young adults. JAMA. 2007;297:2092-2102.