Application Deadline: Monday 8 April 2019, full info on the LSHTM website.
Project Title: Impact of changes in the food environment on food and drink purchasing using large-scale secondary data
Principal Supervisor: Professor Steve Cummins (London School of Hygiene and Tropical Medicine)
Co-Supervisor: Dr Laura Cornelsen (London School of Hygiene and Tropical Medicine)
Co-Supervisor: Dr Andrea Ballatore (Birkbeck, University of London)
Poor diets are increasingly linked to a range of chronic diseases, including cardiovascular disease, cancer and stroke as well as dental caries, obesity and type 2 diabetes and contribute substantially to excess morbidity, mortality, and rising health-care costs (1,2). Features of the built environment, such as increased access to fast-food and poorer access to supermarkets and grocery stores, have been, in turn linked with poor diets. Although the existing body of research looking at the influence of built environment risks to diet and diet-related health outcomes is substantial, the evidence remains inconsistent and largely consists of studies from the U.S. (3). Research to date has focused on the direct effects on health and has not investigated how the specific elements of the local food environment drives purchases of specific foods and how changes in the local food environment change purchasing behaviours – a key part of the causal pathway. Part of the reason for this is limited availability of high quality data on household food purchases for consumption inside and outside of the home. This data, where available, is often cross-sectional, lacks granularity and is often unable to distinguish in sufficient detail from which outlets foods have been purchased.
The aim of this project is to explore whether different elements of the local food environment are associated with changes in purchasing of food and drinks for consumption both inside and outside homes over time and how these may influence diet and dietary outcomes.
1. To construct novel time-varying relative and absolute measures of the local food environment and matched with data on household food purchasing.
2. Examine cross-sectional and longitudinal associations between features of the local food environment and household food and drink purchasing for consumption both in- and outside of the home.
3. Analyse whether these effects are distributed and whether they are modified by markers of socio-economic position, product price and household composition.
4. Utilise the effects of changes in purchasing behaviour to estimate the effect on diet-related health outcomes.
To achieve these objectives, the PhD will take advantage of access to a unique highly disaggregated large-scale commercial dataset on household food and drink purchases for consumption inside and outside homes (Kantar Worldpanel). The dataset comprises product-level scanner information on food purchases for 30,000 UK households for the period 2012-2017 (c210 million observations). These data will be linked through geocoding with measures of the social and built food environment exposures as well as undertaking georeferenced sentiment analysis of social media data. A key part of the thesis will be the creation of these novel environmental exposures by the student based on existing geospatial data on food businesses (e.g. OS Points of Interest, FSA outlet data). A range of advanced statistical and economic models will be employed to undertake analyses including the use of longitudinal and spatial regression methods, and methods to undertake health impact modelling.
Subject areas: epidemiology, economics, geography, statistics, population health
Keywords: food environment, diet, obesity, neighbourhood, built environment