['To determine whether a multicomponent nutrition intervention program at a corporate site reduces body weight and improves other cardiovascular risk factors in overweight individuals.', 'Prospective clinical intervention study.', 'Employees of the Government Employees Insurance Company (GEICO) (N = 113), aged 21 to 65 years, with a body mass index > or =25 kg/m(2) and/or previous diagnosis of type 2 diabetes.', 'A 22-week intervention including a low-fat, vegan diet.', 'Changes in body weight, anthropometric measures, blood pressure, lipid profile, and dietary intake.', 'Multivariate analyses of variance were calculated for clinical and nutrient measures, followed by univariate analyses of variance, to determine the significance of differences between groups in changes over time.', 'Intervention-group participants experienced greater weight changes compared with control-group participants (mean, -5.1 [SE, .6] kg vs. + .1 [SE, .6] kg, p < .0001), as well as greater changes in waist circumference (mean, -4.7 [SE, .6] cm vs. + .8 [SE, .6] cm, p < .0001) and waistratiohip ratio (mean, -.006 [SE, .003] vs. + .014 [SE, .005], p = .0007). Weight loss of 5% of body weight was more frequently observed in the intervention group (48.5%) compared with the control group (11.1%) (chi(2)[1, N = 113] = 16.99, p < .0001).'] Does a multicomponent intervention reduce body weight and cardiovascular risk at a GEICO corporate site?