RE-AIM evaluation of a one-year trial of a combined educational and environmental workplace intervention to lower salt intake in Switzerland

Reducing excessive dietary sodium may reduce cardiovascular disease risk. Environmental and behavioral interventions in workplaces may reduce salt consumption, but information on the effectiveness of workplace nutrition interventions is sparse. We used the RE-AIM framework to evaluate a one-year trial in 2015–2016 of an educational and environmental intervention to lower salt intake of employees in organizations with catering facilities in Switzerland. Five educational workshops for employees and assessments that included 24-hour urine collection were combined with five coaching sessions and food analyses in catering operations. We studied the adoption, reach, implementation, effectiveness, and maintenance of the intervention. Eight of 389 candidate organizations participated in the trial in which 145 (50% men) out of 5794 potentially eligible employees consented to participate, and 138 completed the trial with 13 in the control group. The overall mean change of daily salt intake was −0.6 g from 8.7 g to 8.1 g (6.9%). Though the mean daily salt intake of women was unaltered from 7 g, the mean intake of men declined by −1.2 g from 10.4 g to 9.2 g. Baseline salt intake, sex, and waist-to-height ratio were significant predictors of salt reduction. The analysis also highlighted pivotal determinants of low adoption and reach, and program implementation in catering operations. We conclude that a workplace program of nutrition intervention for employees and catering staff is feasible. The acceptance, effectiveness, and maintenance of nutrition interventions in the workplace require strong employer support. In a supportive food environment, interventions tailored to sex, age, and CVD risk inter alia could be successful.