A two-year randomized weight loss trial comparing a vegan diet to a more moderate low-fat diet

University of North Carolina at Chapel Hill, 2217 McGavran-Greenberg Hall, CB 7461, Chapel Hill, NC 27599-7461, USA.
Obesity (Impact Factor: 4.39). 09/2007; 15(9):2276-81. DOI: 10.1038/oby.2007.270
Source: PubMed

ABSTRACT The objective was to assess the effect of a low-fat, vegan diet compared with the National Cholesterol Education Program (NCEP) diet on weight loss maintenance at 1 and 2 years.
Sixty-four overweight, postmenopausal women were randomly assigned to a vegan or NCEP diet for 14 weeks, and 62 women began the study. The study was done in two replications. Participants in the first replication (N = 28) received no follow-up support after the 14 weeks, and those in the second replication (N = 34) were offered group support meetings for 1 year. Weight and diet adherence were measured at 1 and 2 years for all participants. Weight loss is reported as median (interquartile range) and is the difference from baseline weight at years 1 and 2.
Individuals in the vegan group lost more weight than those in the NCEP group at 1 year [-4.9 (-0.5, -8.0) kg vs. -1.8 (0.8, -4.3); p < 0.05] and at 2 years [-3.1 (0.0, -6.0) kg vs. -0.8 (3.1, -4.2) kg; p < 0.05]. Those participants offered group support lost more weight at 1 year (p < 0.01) and 2 years (p < 0.05) than those without support. Attendance at meetings was associated with improved weight loss at 1 year (p < 0.001) and 2 years (p < 0.01).
A vegan diet was associated with significantly greater weight loss than the NCEP diet at 1 and 2 years. Both group support and meeting attendance were associated with significant weight loss at follow-up.

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Available from: Gabrielle Turner-McGrievy, Aug 15, 2015
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