Constant exposure to fast food restaurants could make people more likely to eat the food at those restaurants and be more obese, according to a new study from the UK.
Researchers found that people who were most exposed to fast food restaurants in their home neighborhoods and near their offices -- as well as on their way to and from home -- had a body mass index (BMI) that was 1.21 points greater than people who were least exposed to the restaurants. The most exposed people were also nearly two times more likely to be obese than the least exposed people.
However, they noted that the study only showed an association, and does not prove that living or working near fast food restaurants causes obesity.
The research, published in the British Medical Journal, is based on data from the Fenland Study, which included 5,442 eligible study participants. All of the participants worked outside the home, lived in Cambridgeshire in the UK, and were between ages 29 and 62. They also completed food frequency questionnaires in order for researchers to estimate how much pizza, fried food, chips, etc. they ate every day (as an indicator of fast food consumption). Researchers also calculated the participants' body mass indexes.
Exposure to fast food restaurants was significantly more common -- 48 percent more common, in fact -- at work than in home neighborhoods. In addition, the average number of fast food restaurants a participant was exposed to on the commute to and from work was 32.
There was an association between grams of fast food consumed each day and exposure to fast food restaurants. People who were the most exposed consumed 5.7 more grams of this food (or 15 percent more consumption) than the least exposed people, researchers found.
"In a week, this translates into an additional 39.9g of takeaway food," they wrote in the study. "This weekly amount constitutes more than half a small serving of McDonald's French Fries (typically 71 g per serving) and about one quarter of the grams of takeaway food purchased per person per week in the UK in 2010."
The researchers also noted that the greatest association between fast food exposure and fast food consumption was at work. "We suggest that time imperatives drive food purchases from more proximal food outlets, selling ready prepared meals, which could partly explain the strong associations observed in our study between these exposures and consumption of takeaway food," they wrote.