People who live or work near to a greater number of takeaway outlets are more likely to eat more takeaway food and to be overweight, but new research indicates that neighbourhoods that are saturated with fast food outlets may be particularly unhealthy for people who are socioeconomically disadvantaged.
The study from the Centre for Diet and Activity Research (CEDAR) at the University of Cambridge, suggests that policies to improve the food environment in towns and cities could be helpful in tackling social inequalities in diet and health.
Nearly two-thirds of adults are overweight or obese in the UK, and it is thought that this may be due in part to increased takeaway food consumption: the amount spent on takeaway foods over the past decade has risen by almost a third (29%) in the UK, where £28 billion worth of takeaway foods are now purchased annually.
To observe the relationships between neighbourhoods, education, diet and obesity, researchers at CEDAR used data from a cohort of almost 6,000 adults aged 29-62 years in Cambridgeshire. Individuals were asked about their highest educational attainment, eating patterns, were weighed and measured by trained researchers, and had the density of takeaway outlets in their home and work neighbourhoods calculated. The results are published today in the American Journal of Clinical Nutrition.
For the first time the researchers observed consistent differences in diet and weight by education at all levels of neighbourhood exposure to takeaway outlets. Furthermore, where exposure to takeaway outlets was greatest, differences in diet and weight across education groups were most pronounced. In other words the availability of takeaways seemed to be amplifying existing social inequalities.
Individuals with greatest exposure to takeaway outlets consumed around a third more unhealthy takeaway food per day if they were the poorest educated (47g per day) than if they were highest educated (36g per day). Over a year, this is the equivalent of over 4kg of extra unhealthy food. The least educated also had the greatest risk of obesity where the exposure to takeaway outlets was highest.
The findings confirm previous studies showing that takeaway food consumption, weight and the likelihood of being obese are all associated with either living or working near high numbers of takeaway food outlets. They also strengthen the evidence showing that eating takeaways and being obese are linked to socioeconomic disadvantage, indicated by a low level of education.
"Neighbourhoods are clearly important in shaping what all of us eat, no matter how educated we are," explains Dr Thomas Burgoine from CEDAR, part of the Medical Research Council Epidemiology Unit at the University of Cambridge. "But this effect appears to be much greater for those with lower levels of education."
Compared to those least exposed and most educated, those most exposed and least educated were over three times more likely to be obese. Dr Burgoine says: "This double burden of neighbourhood and individual level disadvantage goes some way to explaining current UK socioeconomic inequalities in levels of obesity - in other words, why we see more obesity in disadvantaged groups."
The researchers used low educational attainment as an indicator of individual level disadvantage. Low educational attainment is commonly associated with lacking behavioural and economic resources, such as cooking skills, food and nutrition knowledge, adequate cooking equipment and a shopping budget that affords healthy purchases, which may increase the influence of an unhealthy neighbourhood food environment.
Dr Pablo Monsivais, senior author of the study, adds: "Higher educational attainment brings with it many advantages, including more money to spend on fresh, healthier foods, as well as better knowledge of food and nutrition, and the tendency to dedicate more time to preparing meals at home, which we know are healthier than those bought out of the home. Without these advantages, people may be more vulnerable to their environment."
The findings suggest that efforts to improve diets and health by regulating the number of takeaway outlets on our high streets might be particularly effective for those of lower socioeconomic status and therefore help to reduce inequalities in diet and obesity. Such policies are already beginning to be implemented in a number of UK regions and in south Los Angeles, for example. In the UK, people living in deprived neighbourhoods are generally exposed to higher numbers of takeaway food outlets.
"Our results suggest that these policies will be effective across socioeconomic groups, but, critically, particularly for the most disadvantaged. This could help to reduce socioeconomic inequalities in diet and health," says Dr Monsivais. "This is important because attempts to encourage more healthy living at an individual level have largely failed to reduce health inequalities. This failure has been attributed to such initiatives proving especially ineffective among disadvantaged populations."
The study was funded by the British Heart Foundation, Cancer Research UK, the Economic and Social Research Council, the Medical Research Council, the NIHR and the Wellcome Trust.
Burgoine, T et al. Does neighborhood fast-food outlet exposure amplify inequalities in diet and obesity? A cross-sectional study. Am J Clin Nutr; 11 May 2016; DOI: 10.3945/ajcn.115.128132.