Research from the University of East Anglia in Norwich has found children living close to fast food outlets are more likely to be overweight.
The study found older children in particular are more likely to be overweight when living close to the outlets. It is hoped that the findings will help shape planning policy to help tackle childhood obesity.
Prof Andy Jones, who led the research, said: "The results were more pronounced in secondary school children who have more spending power to choose their own food.
"But the association was reversed in areas with more healthy food options available."