Effectiveness of interventions aimed at improving dietary behaviours among people at higher risk of or with chronic non-communicable diseases: an overview of systematic reviews.

Programmes that promote dietary behaviour change for the prevention of chronic disease must include components that are rooted in best practice and associated with effectiveness. The purpose of this overview of systematic reviews was to examine the characteristics and dietary behaviour change outcomes of nutrition interventions among populations with or at risk of non-communicable chronic diseases. Systematic reviews of randomised controlled trials (RCTs) testing dietary behaviour change interventions published between January 2006 and November 2015 were identified via searches in Cochrane Library, PubMed, EMBASE and PsycINFO. Quality of reviews were appraised using AMSTAR. Dietary behaviour change and intervention details were extracted and systematically summarised. Fifteen articles met the inclusion criteria. Dietary behaviour changes in response to nutrition interventions were significant in over half of interventions. Reducing dietary fat and increasing fruits and vegetables were the most common behaviour changes. The characteristics of nutrition interventions and their relationship to effectiveness for dietary behaviour change among chronic disease or at-risk populations were reported inconsistently. However, associative evidence exists to support more frequent contacts and the use of specific behaviour change techniques. No clear relationships were found between effectiveness and intervention setting, mode of delivery or intervention provider, although some population-specific relationships were identified. Interventions that promote long-term maintenance of dietary behaviour changes are lacking in the literature. This comprehensive umbrella review identifies specific characteristics of interventions that are associated with effectiveness in interventions that promote dietary behaviour change among different at-risk populations. In order to maximise outcomes, public health, health promotion and healthcare organisations should consider these results in order to inform the development and improvement of nutrition programmes.