Associations of Food Outlet Densities with Obesity Measures Identify Fish and Chip Shops as a Uniquely Important Problem.

Abstract

Increases in the number of food outlets have been proposed as a key factor driving obesity. This study aimed to investigate the association between the densities of food establishments serving meals (excluding supermarkets and grocery stores), with body mass index (BMI), waist to hip ratio (WHR) and percentage of body fat among middle-aged adults in the UK. BMIs, WHR, %fat and socioeconomic factors were obtained from 456,079 individuals from the UK Biobank and averaged across 923 postcode districts (PD). The number of Fast-Food Restaurants (FFRs), Full-Service Restaurants (FSRs), delivery shops, takeaways, fish and chip shops, pubs and cafes were also obtained for each PD. We adjusted the obesity measures for deprivation level, education, employment, ethnicity, household size, household income and age. After adjustment, the density of fish and chip shops (per 1000 population) was positively associated with BMI and %fat for both sexes (males: BMI converted (exponentiated coefficient) β = 0.5, R2 = 4.14%, p < 0.0001; %fat converted β = 0.8, R2 = 3.32%, p < 0.0001; females: BMI converted β = 0.9, R2 = 5.31%, p < 0.0001; %fat converted β = 1.4 R2 = 4.65%, p < 0.0001). The densities of FFRs and delivery shops (per 1000 population) were not related to the adjusted obesity measures among males and females, except BMI in males where FFRs were significantly negatively associated. The densities (per 1000 population) of FSRs, pubs, cafes and total food outlets were all significantly inversely related to the obesity measures for both sexes. The number of fish and chip shops per 1000 individuals was significantly positively associated with obesity in middle-aged adults in the UK. A negative association between the other types of food outlet densities and the measures of obesity suggests access to such establishments is not a major driver of obesity. This is potentially because the food supplied at such establishments is not significantly less healthy than what is eaten elsewhere including at home (and may even be better). Paying attention only to fast food and/or full-service restaurants in intervention policy will likely not be effective. Policy intervention should potentially focus on the numbers of fish and chip shops and the deep-fried food served in such restaurants.