title: Insulin resistance predicts the effectiveness of different glycemic index diets on weight loss in non-obese women.
abstract: OBJECTIVE
  The present study aimed to evaluate whether baseline insulin resistance (IR) modify weight change associated to glycemic index (GI) of the diet.
  
  
  METHODS
  This is a secondary analysis of a randomized GI intervention according to baseline HOMA-IR. Middle-aged (25-45 years), non-obese (BMI 23-29.9 kg/m²) women were randomized to low or high GI diets matched on total energy, macronutrient composition, and fiber content. Both groups received dietary counseling based on a small energy restriction (100-300 kcal/day). Women were classified in two groups according to their baseline HOMA-IR: IR (n = 64) and non-IR (n = 121).
  
  
  RESULTS
  At baseline, IR and non-IR groups had similar BMI (26.7 vs. 26.3 kg/m²; p = 0.21), but the IR group presented with higher waist circumference (82.7 vs. 80.8 cm; p = 0.02) and showed greater weight loss after 12 months of follow-up (-1.6 vs. -1.1 kg; p = 0.01), mainly among those in a high-GI diet (-2.1 vs. -1.0 kg; p = 0.005) compared to the non-IR group (-1.4 vs. -0.8 kg; p = 0.04).
  
  
  CONCLUSIONS
  The high-GI group showed statistically significant higher reduction in body weight, mainly among those women with baseline IR . Low-GI diet did not facilitate weight loss neither in IR women nor in non-IR women.
authors.affiliation: Department of Clinical and Experimental Medicine, Institute of Social Medicine, State University of Rio de Janeiro, Rio de Janeiro, Brazil. mffmediano@gmail.com
authors.forename: Mauro Felippe Felix
authors.initials: MF
authors.lastname: Mediano
authors.forename: Rosely
authors.initials: R
authors.lastname: Sichieri
mesh_terms: D000328:Adult; D015992:Body Mass Index; D004038:Diet, Reducing; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000145:classification / Q000378:metabolism*; D004043:Dietary Fiber / Q000008:administration & dosage / Q000378:metabolism; D002149:Energy Intake; D005260:Female; D038321:Glycemic Index; D006801:Humans; D007333:Insulin Resistance; D008875:Middle Aged; D050177:Overweight / Q000178:diet therapy* / Q000378:metabolism*; D016896:Treatment Outcome; D055105:Waist Circumference / Q000502:physiology; D015431:Weight Loss / Q000502:physiology*
chemical_list: D004040:Dietary Carbohydrates; D004043:Dietary Fiber