a1 Department of Nutrition, School of Public Health, University of São Paulo, Av. Dr Arnaldo 715, São Paulo, Postal Code: 01246-904, SP, Brazil
a2 Center for Epidemiological Studies in Health and Nutrition, University of São Paulo, São Paulo, SP, Brazil
a3 Department of Health, Clinical and Institutions, Institute for Health and Society, Federal University of São Paulo, São Paulo, SP, Brazil
Objective To evaluate the impact of a worksite intervention to prevent weight gain among adult workers.
Design A controlled community trial was performed by dividing the workers into two groups: intervention group (IG) and control group (CG). The theoretical framework applied was Intervention Mapping Protocol and the intervention was implemented through interactive software for weight self-monitoring. To evaluate the impact of the intervention, the differences in weight, BMI and waist circumference between the IG and CG were assessed before and 6 months after the intervention by regression models. Additionally, the sustainability of the intervention was evaluated at 12 months after the intervention.
Settings São Paulo, Brazil.
Subjects Four companies; 281 workers for the analysis of effectiveness and 427 for the analysis of sustainability.
Results The intervention resulted in significant reductions in weight, BMI and waist circumference in the IG compared with the CG. The impact of the intervention on IG individuals’ body weight was −0·73 kg, while the weight of CG individuals increased. IG individuals with adequate initial weights did not show significant variations, while those who were overweight demonstrated a significant reduction in body weight. The intervention resulted in a reduction of 0·26 kg/m2 in BMI and 0·99 cm in waist circumference, and the sustainability analysis after 12 months showed a continued reduction in body weight (−0·72 kg).
Conclusions The behavioural intervention was effective, resulting in weight maintenance among participants with adequate initial weight and in significant reductions among those who were overweight. More research on longer-term weight maintenance is needed.
(Received September 28 2012)
(Revised May 15 2013)
(Accepted June 12 2013)
(Online publication August 20 2013)