Weight-loss experience of black and white participants in NHLBI-sponsored clinical trials.

We examined race-specific weight-loss results from two randomized, multicenter trials; the Hypertension Prevention Trial (HPT) and the Trials of Hypertension Prevention (TOHP). Mean weight change from baseline averaged 2.2 kg less in black women than in white women during 18 mo of follow-up in TOHP and 2.7 kg less during 36 mo of follow-up in HPT. Mean weight loss averaged 2.0 kg less in black than in white men in TOHP and 1.4 kg less in HPT. Because of greater weight gain in black control subjects, a comparison of net weight loss (change in intervention minus change in control participants, within-race) showed a less marked difference than did black-white differences in weight loss within the actively treated group. Thus, relative to weight that would have been gained without the intervention, the experience of blacks and whites was more similar. Racial differences in weight loss may result from a combination of behavioral, sociocultural, biological, and programmatic factors.