Randomized trial of nutrition education added to internet-based information and exercise at the work place for weight loss in a racially diverse population of overweight women

Abstract

Objective: Obesity in the United States is highly prevalent, approaching 60% for black women. We investigated whether nutrition education sessions at the work place added to internet-based wellness information and exercise resources would facilitate weight and fat mass loss in a racially diverse population of overweight female employees.

Methods: A total of 199 (average body mass index 33.9±6.3 kg m(-2)) nondiabetic women (57% black) at our institution were randomized to a 6-month program of either internet-based wellness information (WI) combined with dietitian-led nutrition education group sessions (GS) weekly for 3 months and then monthly with shift in emphasis to weight loss maintenance (n=99) or to WI alone (n=100). All were given access to exercise rooms convenient to their work site. Fat mass was measured by dual-energy X-ray absorptiometry.

Results: WI+GS subjects lost more weight than WI subjects at 3 months (-2.2±2.8 vs -1.0±3.0 kg, P>0.001). Weight (-2.7±3.9 vs -2.0±3.9 kg) and fat mass (-2.2±3.1 vs -1.7±3.7 kg) loss at 6 months was significant for WI+GS and WI groups (both P<0.001), but without significant difference between groups (both P>0.10); 27% of the WI+GS group achieved 5% loss of initial weight as did 18% of the WI group (P=0.180). Blacks and whites similarly completed the study (67 vs 74%, P=0.303), lost weight (-1.8±3.4 vs -3.3±5.2 kg, P=0.255) and fat mass (-1.6±2.7 vs -2.5±4.3 kg, P=0.532), and achieved 5% loss of initial weight (21 vs 32%, P=0.189), irrespective of group assignment.

Conclusion: Overweight women provided with internet-based wellness information and exercise resources at the work site lost weight and fat mass, with similar achievement by black and white women. Additional weight loss benefit of nutrition education sessions, apparent at 3 months, was lost by 6 months and may require special emphasis on subjects who fail to achieve weight loss goals to show continued value.

Figure 1

Flow chart of participants in a protocol randomizing participants to internet-based wellness information and nutrition education group sessions (WI+GS) vs wellness information only (WI).

Figure 2

Weight loss for the 158 women (79 receiving internet wellness information combined with nutrition education group sessions (WI+GS), 79 receiving internet wellness information alone (WI)) who participated in the protocol for at least 3 months. Repeated-measures mixed-effects models (adjusted for age, race and baseline BMI) were used to assess the effect of 3 and 6 months participation and WI+GS vs WI assignment on weight loss.