Dietary glycemic index is associated with less favorable anthropometric and metabolic profiles in polycystic ovary syndrome women with different phenotypes

Objective: To compare glycemic index (GI) in the usual diet of polycystic ovary syndrome (PCOS) and control women and to investigate whether dietary GI is associated with body composition and anthropometric and metabolic variables across PCOS phenotypes. Design: Cross-sectional study. Setting: University hospital outpatient clinic. Patient(s): Sixty-one women with PCOS and 44 nonhirsute women with ovulatory cycles. Intervention(s): Metabolic work-up, biochemical and hormonal assays, assessment of body composition and rest metabolic rate, physical activity (pedometer), and food consumption (food frequency questionnaire). Main outcome measure(s): GI, glycemic load, dietary intake, and hormone and metabolic profile in PCOS versus control and in PCOS women stratified by tertiles of GI and PCOS phenotype. Result(s): Mean age was 23.7 +/- 6.3 years. Participants with PCOS had higher body fat percentage, fasting insulin, insulin resistance, lipid accumulation product, and androgen levels compared with control women. PCOS and control women in the highest tertile of GI had higher body mass index and waist circumference than those in the lowest tertile. Dietary GI was higher in the classic PCOS group. Obesity and this more severe PCOS phenotype explained 28.3% of variance in dietary GI. Conclusion(s): Dietary GI is increased in the classic PCOS phenotype and associated with a less favorable anthropometric and metabolic profile. Obesity and classic PCOS phenotype are age-independent predictors of higher dietary GI. (Fertil Steril (R) 2013;100:1081-8. (C) 2013 by American Society for Reproductive Medicine.)