title: Insulin sensitivity determines the effectiveness of dietary macronutrient composition on weight loss in obese women.
abstract: OBJECTIVE
  To determine whether macronutrient composition of a hypocaloric diet can enhance its effectiveness and whether insulin sensitivity (Si) affects the response to hypocaloric diets.
  
  
  METHODS
  Obese nondiabetic insulin-sensitive (fasting insulin < 10 microU/mL; n = 12) and obese nondiabetic insulin-resistant (fasting insulin > 15 microU/mL; n = 9) women (23 to 53 years old) were randomized to either a high carbohydrate (CHO) (HC)/low fat (LF) (60% CHO, 20% fat) or low CHO (LC)/high fat (HF) (40% CHO, 40% fat) hypocaloric diet. Primary outcome measures after a 16-week dietary intervention were: changes in body weight (BW), Si, resting metabolic rate, and fasting lipids.
  
  
  RESULTS
  Insulin-sensitive women on the HC/LF diet lost 13.5 +/- 1.2% (p < 0.001) of their initial BW, whereas those on the LC/HF diet lost 6.8 +/- 1.2% (p < 0.001; p < 0.002 between the groups). In contrast, among the insulin-resistant women, those on the LC/HF diet lost 13.4 +/- 1.3% (p < 0.001) of their initial BW as compared with 8.5 +/- 1.4% (p < 0.001) lost by those on the HC/LF diet (p < 0.04 between two groups). These differences could not be explained by changes in resting metabolic rate, activity, or intake. Overall, changes in Si were associated with the degree of weight loss (r = -0.57, p < 0.05).
  
  
  CONCLUSIONS
  The state of Si determines the effectiveness of macronutrient composition of hypocaloric diets in obese women. For maximal benefit, the macronutrient composition of a hypocaloric diet may need to be adjusted to correspond to the state of Si.
authors.affiliation: Department of Medicine, University of Colorado Health Sciences Center, Denver, CO, USA.
authors.forename: Marc-Andre
authors.initials: MA
authors.lastname: Cornier
authors.forename: W Troy
authors.initials: WT
authors.lastname: Donahoo
authors.forename: Rocio
authors.initials: R
authors.lastname: Pereira
authors.forename: Inga
authors.initials: I
authors.lastname: Gurevich
authors.forename: Rickard
authors.initials: R
authors.lastname: Westergren
authors.forename: Sven
authors.initials: S
authors.lastname: Enerback
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Eckel
authors.forename: Marc L
authors.initials: ML
authors.lastname: Goalstone
authors.forename: James O
authors.initials: JO
authors.lastname: Hill
authors.forename: Robert H
authors.initials: RH
authors.lastname: Eckel
authors.forename: Boris
authors.initials: B
authors.lastname: Draznin
mesh_terms: D000328:Adult; D001481:Basal Metabolism; D015992:Body Mass Index; D004038:Diet, Reducing; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D002149:Energy Intake; D004734:Energy Metabolism; D005215:Fasting; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome; D015431:Weight Loss
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D007328:Insulin