title: Decreases in dietary glycemic index are related to weight loss among individuals following therapeutic diets for type 2 diabetes.
abstract: This study assessed the effect of changes in glycemic index (GI) and load (GL) on weight loss and glycated hemoglobin (HbA1c) among individuals with type 2 diabetes beginning a vegan diet or diet following the 2003 American Diabetes Association (ADA) recommendations. The study was a 22-wk, randomized trial of 99 participants with type 2 diabetes who were counseled to follow 1 of 2 diet treatments. GI and GL changes were assessed based on 3-d dietary records. The relationships between GI/GL and changes in weight and HbA1C were calculated. In an intention-to-treat analysis (n = 99), the vegan group reduced GI to a greater extent than the ADA group (P < 0.05), but GL was reduced further in the ADA than the vegan group (P < 0.001). GI predicted changes in weight (P = 0.001), adjusting for changes in fiber, carbohydrate, fat, alcohol, energy intake, steps per day, group, and demographics, such that for every point decrease in GI, participants lost ~0.2 kg (0.44 lb). GI was not a predictor for changes in HbA1C after controlling for weight loss (P = 0.33). Weight loss was a predictor of changes in HbA1C (P = 0.047). GL was not related to weight loss or changes in HbA1C. A low-GI diet appears to be one of the determinants of success of a vegan or ADA diet in reducing body weight among people with type 2 diabetes. The reduction of body weight, in turn, was predictive of decreasing HbA1C.
authors.affiliation: Department of Nutrition, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA. McGrievy@mailbox.sc.edu
authors.forename: Gabrielle M
authors.initials: GM
authors.lastname: Turner-McGrievy
authors.forename: David J A
authors.initials: DJ
authors.lastname: Jenkins
authors.forename: Neal D
authors.initials: ND
authors.lastname: Barnard
authors.forename: Joshua
authors.initials: J
authors.lastname: Cohen
authors.forename: Lise
authors.initials: L
authors.lastname: Gloede
authors.forename: Amber A
authors.initials: AA
authors.lastname: Green
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000032:analysis*; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy*; D003927:Diet, Diabetic; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D015431:Weight Loss
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin