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


METHODS
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.


RESULTS
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).


CONCLUSIONS
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.
Turner-McGrievy
Gabrielle M
GM
University of North Carolina at Chapel Hill, 2217 McGavran-Greenberg Hall, CB 7461, Chapel Hill, NC 27599-7461, USA. brie@unc.edu
Barnard
Neal D
ND
Scialli
Anthony R
AR
D000368:Aged; D001835:Body Weight; D018752:Diet, Fat-Restricted / Q000379:methods*; D004038:Diet, Reducing / Q000379:methods*; D014676:Diet, Vegetarian; D002149:Energy Intake; D005260:Female; D006801:Humans; D008875:Middle Aged; D050177:Overweight / Q000178:diet therapy*; D017698:Postmenopause; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss