New research from the Chinese Academy of Sciences and University of Aberdeen published in the American Journal of Clinical Nutrition suggests that higher densities of fast food (and full service) restaurants are not associated with higher levels of obesity in the USA.
The researchers investigated the relationship between densities of full service and fast food restaurants and the prevalence of obesity in the United States of America.
The team analysed data collected in 2012 by the US Centers for Disease Prevention and Control (CDC) and compared it to data related to fast-food and full-service restaurant density as reported by the US Department of Agriculture's Economic Research Service, but found no link between the two.
Professor John Speakman of the University of Aberdeen and the Chinese Academy of Sciences, commented: "If fast food establishments have driven the obesity epidemic then one would predict that in areas where there are more of these establishments the obesity prevalence would be higher.
"However, what we actually found was that the more restaurants that there were in an area (both fast food and full service), the lower the obesity rate. This was principally because areas which tended to have the most restaurants were occupied by residents with a higher levels of education and more disposable income, which are known factors linked to lower obesity levels. When we corrected for these factors the relationship between obesity and restaurant density disappeared."
The authors say that a potential explanation for the absence of a relationship is that on average Americans only consume about 15% of their total calorie intake in restaurants.
"Rising levels of obesity are leading to severe health complications and massive healthcare spending. As such, research into what is causing this worrying trend is hugely important if we are going to tackle the obesity epidemic."
The work has important policy implications for governments attempting to tackle the obesity problem.
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