Effectiveness of workplace interventions in Europe promoting healthy eating: a systematic review

Background: The worksite is a promising setting for health promotion. This review summarizes the evidence of effect of intervention studies in European countries promoting a healthy diet solely and in combination with increasing physical activity at the workplace. Methods: A systematic review of published literature was carried out. Inclusion criteria were: studies conducted in European countries; papers published from 1 January 1990 to 1 October 2010; worksite-based interventions promoting a healthy diet solely or in combination with physical activity; primary prevention; measurement of anthropometrical or behavioural change and adults (epsilon 18 years old). Levels of evidence for intervention effectiveness on behavioural determinants, nutrition and physical activity behaviours and body composition and the quality of the included interventions were assessed. Results: Seventeen studies solely focusing on promotion of a healthy diet were identified. Eight were educational, one used worksite environmental change strategies, and eight used a combination of both (multi-component). None of the interventions were rated as 'strong'; seven met the criteria for 'moderate' quality. The reviewed studies show moderately evidence for effects on diet. Thirteen studies focusing both on nutrition and physical activity (nine educational and four multi-component studies) were identified. Ten were rated as having 'weak' and three as having 'moderate' methodological quality, providing inconclusive evidence for effects. Conclusion: Limited to moderate evidence was found for positive effects of nutrition interventions implemented at the workplace. Effects of workplace health promotion interventions may be improved if stronger adherence to established quality criteria for such interventions is realized.