P-148: Effect of A Low Glycemic Index Diet on Insulin Resistance and Reproductive Hormones

Background: Polycystic ovary syndrome (PCOS) is the most common endocrine disease in women affecting 5-10% of those of childbearing age. The majority of women with PCOS, regardless of weight, have a form of insulin resistance that is intrinsic to the syndrome. Obese women with PCOS have an added burden of insulin resistance related to their adiposity. Given the association of obesity and insulin resistance with PCOS, weight management is recommended as first-line management for women with PCOS. In general population, a diet lower in GL from reducing GI or carbohydrate is associated with greater weight loss and maintenance proposed to be a result of reduced appetite and energy intake from increasing protein,reducing carbohydrate intake or lowering GI, or related to a diuretic effect with an acute low-carbohydrate diet. Because the majority of women with PCOS show a marked compensatory hyperinsulinema after carbohydrate ingestion, there may be specific advantages of diets with a low Gl in this group. The aim of this review study was to investigate the effects of a low-glycemic-load diet on reproductive hormones, inflammatory markers, lipids, glucose, and insulin levels in obese women with PCOS. Materials and Methods: This review article was prepared by studdying of articles obtained from Google, pub med sites with key words such as polycystic ovary syndrome; insulin sensitivity; dietary intervention, glycemic index, reproductive hormones. Results: Barr etal. (2013) studied the efficacy of an isocaloric low-GI dietary intervention on insulin sensitivity, in women with PCOS. A non randomized 12-week low-GI dietary intervention, preceded by a 12-week habitual diet control phase and pro - ceeded by a 12-week follow-up phase was conducted. Measures of insulin sensitivity and nonesterified fatty acid improved after intervention. Marsh etal. (2010) assigned overweight and obese women with PCOS (n= 96) to consume either an ad libitum low- GI diet or a macronutrient-matched healthy diet and followed the women for 12 months or until they achieved a 7% weight loss. They reported increased menstrual regularity for 95% of women after a low-GI ad libitum weight-loss diet compared with 63% of women following a standard healthy ad libitum weight-loss diet. Pregnancies did not differ by diet composition.Both the low-GI and the conventional diets led to similar improvements in blood lipid, androgenic hormones concentrations, and markers of inflammation. Among the biochemical measures, only serum fibrinogen concentrations showed significant differences between diets. Herriot etal prescribed a reduced glycaemic load diet, with energy reduction in overweight PCOS patients. At the follow-up appointment, BMI and waist circumference significantly decreased in overweight patients. 71% of women self-reported hypoglycaemia initially; this was reduced to 13% at follow-up.Galletly etal. (2007) examined Twenty-five overweight women with PCOS. They were randomly allocated to the low protein - high carbohydrat (LPHC) or high protein - low carbohydrate (HPLC) diet for 16 weeks. The HPLC diet was associated with significant reduction in depression and improvement in self-esteem. There was no change in any psychological measures for the LPHC group. There was no difference in weight loss between the groups. HPLC diets may be associated with better compliance and hence be more successful in the long term treatment of obesity. Douglas etal. (2006) conducted a 16-day acute weight-maintenance intervention. Three diet compositions were compared (a monounsaturated fatty acid(MUFA)enriched, a conventional healthy diet(STD diet)and a low-carbohydrate diet with a total energy intake of approximately 2,000 kcal/day.The results indicated that fasting insulin was lower following the Low CHO diet relative to the STD diet. The change in mean body weight during the Low CHO dietary intervention was significantly greater than that for the MUFA dietary intervention and tended to be greater than that for the STD dietary intervention. It is possible that the greater weight loss in this study is related to the lower GL in the low-carbohydrate diet, because all diets were of equivalent energy and protein intake. Conclusion: In conclusion, low-GI diet may provide an additional advantage over and above that of a conventional healthy diet in managing the underlying insulin resistance, cardiovascular risk, and irregular menstrual patterns in women with PCOS who are overweight.