Low-Income Neighborhoods Mean More Big Macs
The scientists found that for England and Scotland there is a positive correlation between neighborhood deprivation and the presence of McDonald's restaurants.
The study did not, however, find that the McDonald's, or any other brand of fast food, directly caused obesity.
The results appear in the November issue of the American Journal of Preventive Medicine.
"From previous research we know that the consumption of 'fast-food,' which is high fat and energy dense, is associated with obesity," says lead author Steven Cummins Ph.D., of the University of London. "Our study investigates whether opportunities to consume fast food are greater in poorer areas, using McDonald's restaurants as a case study.".
The most important implication of this finding for public health, says Karen Glanz, Ph.D., director of the Prevention Research Center at Emory University in Atlanta, is the evidence "there may be a greater supply of - or easier access to - cheap food, generally of low nutritional value, in less affluent neighborhoods.".
Last year, the same journal reported that in New Orleans, predominantly black and low-income neighborhoods had 2.4 fast food restaurants per square mile, while white neighborhoods had only 1.5. In that study, author Jason Block, M.D., mapped the placement of restaurants such as Church's Chicken, Pizza Hut, Subway, Burger King and Taco Bell.
"More convenient access likely leads to the increased consumption of fast food in these populations," said Block, who suggested the reasons could be less access to healthier food, consumer preference for fast food or that "because of limited financial resources, black and low-income populations may simply seek out the most calories for the lowest price."
In January 2005, Cummins and his co-investigators gathered and analyzed data on population, deprivation, and the location of McDonald's Restaurants for 38,987 small areas in Scotland and England.
The scientists calculated "deprivation" using a variety of data, including current income, employment, health, education and housing, and ranked the areas by this standard. They measured the density of McDonald's restaurants per 1,000 people for each area and looked for statistical correlations between neighborhood deprivation and density of McDonald's outlets.
The scientists say their findings point to possible environmental reasons for the greater prevalence of obesity in poorer areas in England and Scotland.
"Of course, correlation is not causation," says Simone French, Ph.D., of the division of epidemiology and community health at the University of Minnesota Medical School. "So we cannot say that McDonald's causes the poor to be overweight by building more outlets in the poor neighborhoods. McDonalds' might build food outlets in deprived areas because there is a ready market there.
However, French adds that the new data "support the idea that environmental access to inexpensive, high-energy, high-fat foods is greater in neighborhoods where those populations are greater risk for obesity reside.".
Cummins agrees that a causal relationship between poverty, obesity and the presence of McDonald's cannot be deduced from these findings, "but the location of fast food outlets certainly seems to merit further investigation, given the public health problem posed by obesity," he says.
A spokesman for McDonald's USA was asked to comment on the findings and did not reply.