Background The concept of an ‘obesogenic environment’ a term first used in 1997 has become embedded in Public Health and health geography research. Research suggests that deprived populations in Britain not only have worse access to sources of affordable, healthy foodstuffs, but they also appear to be more exposed to take-away outlets offering cheap, energy-dense food. However measuring the relationship between socio-economic factors and food geography is methodologically complex. This observational study has two aims. Firstly, to describe the availability of pre-prepared hot food in a large urban population, with reference to walk-time geography and secondly, to explore the association between access to take-away outlets and neighbourhood deprivation.
Methods Using Geographical Information System (GIS) software, we measured access to fast food outlets from a large number of randomly generated points (n = 3803) in residential areas of two Local Authorities in central England. Two regression models were built. One modelled the relationship between deprivation and walking distance to the nearest outlet and the other modelled the relationship between deprivation and the number of outlets within a 640 metre ‘short walk’. Adjustments were made for interactions, road connectivity and population density.
Results After adjustment for other variables, we found a statistically significant association (p < 0.001) between deprivation and fast food accessibility. Points in poorer neighbourhoods were closer to an outlet and had a greater density of outlets within a short walking distance. The effect size was modest however. Adjusting for other variables, our model predicted points at the 75th centile of deprivation were about two minutes closer to the nearest outlet by foot, compared to points at the 25th centile of deprivation (467 m, lcl = 455m, ucl = 480 m compared to 603 m, lcl = 588 m, ucl = 618 m). In the density analysis, our model predicts that there will be fewer than one outlet in a 640 metre walk where deprivation is at the 25th centile (0.84, lcl = 0.78, ucl = 0.91) and at least one in the same radius at the 75th centile (1.41, lcl = 1.34, ucl = 1.48).
Conclusion Many Local Authorities, including those in this study, have policies to restrict the growth of take-away outlets, especially near to schools. However we concluded that the existing food landscape already has an abundance of outlets and all neighbourhoods both deprived and less deprived have a large choice and ready access. This calls into question how effective planning laws will be in modifying the food environment.