Key Studies Physical Environment Interventions

What is the potential impact of reducing portion sizes in worksite cafeterias?

Reducing the portion sizes of foods available in restaurants and cafeterias is one promising approach to reducing energy intake, but there is little evidence of its impact from randomised studies in field settings. In this paper, we provide the results of a pilot trial estimating the potential impact of reducing portion sizes of targeted foods in worksite cafeterias. Feedback after the intervention suggested it was broadly acceptable to customers and cafeteria staff. Each of the six cafeterias showed a reduction in daily energy purchased from intervention categories, but the overall reduction across all sites of 8.9% was not statistically significant. The results of this trial suggest that reducing portion sizes could be effective in reducing energy purchased from targeted food categories, but also that future studies will need to address factors that prevented optimal implementation, including site dropout and only reducing portion sizes of a limited range of products.

Impact of reducing portion sizes in worksite cafeterias: a stepped wedge randomised controlled pilot trial. Hollands GJ, Cartwright E, Pilling M, Pechey R, Vasiljevic M, Jebb SA, Marteau TM, 2018

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The TIPPME intervention typology for changing environments to change behaviour

In a new paper, published in Nature Human Behaviour, we introduce a new framework we have developed: the Typology of Interventions in Proximal Physical Micro-Environments (TIPPME). This provides a way to classify and describe an important class of interventions to change selection, purchase and consumption of food, alcohol and tobacco.

Understanding interventions that change behaviour outside of conscious awareness

In a paper published in Health Psychology Review, we have proposed a framework for describing or categorising interventions to change behaviour by the degree to which their effects may be considered non-conscious. This is important because unhealthy behaviours often occur directly in response to environmental cues outside of conscious awareness, meaning that interventions that target non-conscious rather than conscious processes may have significant potential to shape healthier behaviours and improve health. However, examining this key premise requires a practicable conceptual framework that can be used to better describe and assess these interventions. This paper builds on a previous analysis by the same authors highlighting the importance of targeting automatic processes to change behaviour, published in Science in 2012.

Non-conscious processes in changing health-related behaviour: a conceptual analysis and framework. Hollands, Marteau, & Fletcher.

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