Interventions to promote healthy eating: a systematic scoping review of regulatory approaches

Abstract

BackgroundNutrient-poor diets, especially if high in fat and sugar, are associated with an estimated 70 000 excess deaths annually in the UK. Multifactorial strategies are needed to address this burden of ill health. Government regulations provide a framework for action, setting standards that can be monitored. In this systematic scoping review, we considered the effectiveness of regulatory interventions to promote healthy eating. MethodsThe review (PROSPERO #CRD42013002998) comprised a systematic scoping review of regulatory interventions directed at healthy eating, and two in-depth reviews on (1) regulatory strategies to reduce artificial trans-fats in food and (2) school-based fruit and vegetable initiatives. As a systematic scoping review, we followed Cochrane and other systematic review guidance, but the search was designed to be comprehensive rather than specific, and data were synthesised to map the published work. We systematically searched for studies of regulations, rules, and legislation (regulation) to affect healthy eating. Regulations might seek to affect dietary behaviour (food consumption) or to control the nutritional content of food (food production) by specifying levels of individual nutrients such as artificial trans-fats or salt. Regulations to facilitate healthier choices may alter food environments though labelling, calorie display, marketing or advertising controls, food served in schools or child care, zoning and urban planning regulations, restrictions to benefits schemes, and taxes or subsidies. Population-level initiatives and targeting population subgroups were included. Outcomes could be long term, intermediate, or short term. Primary research studies with a recognisable research method were included; those of indirect and non-regulatory interventions were excluded. We searched Medline, Embase, ISI Web of Knowledge, and EconLit from their start dates to the end of December, 2012; Google Scholar for grey literature, including unpublished research or government reports; and bibliographies by hand. 10% of titles and abstracts were independently double screened. A data extraction form, which also assessed risk of bias, was derived from Cochrane Effective Practice and Organisation of Care guidelines, with a subsample of studies extracted in duplicate. FindingsWe screened 38 162 de-duplicated records, of which 80 were included in the scoping review. Eligible studies were analysed by narrative synthesis because of their heterogeneity. Studies of nutrition claims and information labels on packaging or menus (11), and compliance with school food standards (25), occurred most frequently. 13 studies examined artificial trans-fat controls through maximum limits or labelling, which achieved good compliance since measured levels were consistently below legislated maxima. Six studies of school-based fruits and vegetables reported intake increased by 0·5 to 1 portion per day, although changes were not sustained after a programme ceased. The remaining studies reported on marketing regulations (four), taxes or subsidies (15), and multi-component regulations (six). We identified no studies assessing environments or enabling healthier choices through food distribution or retail. InterpretationRegulations can achieve compliance in terms of increasing the proportion of food items, people, or organisations that accord with the regulation; for example, the proportion of schools serving food that meets a required standard or the proportion of food items for sale that contain less than a legal maximum of artificial trans-fats. Whether regulations affect food choices, nutrition, obesity, or other health outcomes is unclear, since these effects have not been assessed. Strategies that reduce artificial trans-fats might improve diets without affecting individual behaviours, although reinforcing consumer engagement should strengthen public health messages while inducing food producers to reformulate. School-based fruits and vegetables encourage children to eat more during the programme, although the intention is also to encourage healthier food choices over the long term. Understanding the effectiveness and costs of regulatory interventions will highlight where government-led action could help promote healthier diets in the population. FundingThe Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence and the UK MRC (U105960389). Funding from the British Heart Foundation, Economic and Social Research Council, MRC, NIHR, and the Wellcome Trust, under the auspices of the UK CRC, is gratefully acknowledged.