Teens who attend classes within one-tenth of a mile of a fast-food outlet are more likely to be obese than peers whose campuses are located farther from the lure of quarter-pound burgers, fries and shakes.
Those are the findings of a recent study by researchers from UC Berkeley and Columbia University seeking a link between obesity and the easy availability of fast food. The academics studied body-fat data from more than 1 million California ninth-graders over an eight-year period, focusing on the proximity of the school to well-known chains including McDonald's, Burger King, KFC, Taco Bell and Pizza Hut.
Their conclusion: Fast food and young waistlines make lousy neighbors.
The presence of an outlet within easy walking distance of a high school -- about 530 feet or less -- resulted in a 5.2% increase in the incidence of student obesity compared with the average for California youths, a correlation deemed "sizable" according to the findings.
The link vanished when these fast-food joints were located farther from campus, presumably because students couldn't easily reach them. Nor was it present in schools located near full-service eateries, whose prices and service times don't typically match student budgets, tastes or schedules.
"Fast food offers the most calories per price compared to other restaurants, and that's combined with a high temptation factor for students," said Stefano DellaVigna, a UC Berkeley economist and one of the paper's authors.
The researchers said cities concerned about battling teen obesity should consider banning fast-food restaurants near schools.
At Fullerton Union, one-third of the ninth-graders examined over the eight-year study period were obese. That compares with a 27% rate at La Habra High School over the same period. Located just six miles from Fullerton Union, La Habra High has similar demographics, but its neighboring fast-food eateries are situated farther from the entrance to its campus.
Fullerton Union ninth-grader Anyea Wilson said she's consumed more McDonald's fare than ever before since starting at the school last year.
"I get ice cream, French fries, double cheeseburgers, all that stuff," the student said. "I know it's not very good for you, but I eat it because that is the closest place to school."
Sophomore Daniel Bannes is partial to cheeseburgers, fries and what he and his friends call the Hulk, a large drink containing a sugary mix of orange Hi-C and blue Powerade.
Daniel said he had stopped ordering Big Macs because he was worried about the calories; a single sandwich packs 540 of them. Still, he likes having McDonald's so close.
"We all hang there after school and kick it," Daniel said.
The findings are likely to fuel the debate over what's driving America's obesity epidemic.
Concerned about growing rates of diabetes and heart disease -- particularly among young people -- state and local governments nationwide are taking aim at fatty, high-calorie foods.
California has been one of the most aggressive. Students can no longer purchase soda or junk food in Golden State schools. Some districts won't allow bake sales. California has banned artery-cloggingtrans fats, and Los Angeles has a one-year moratorium on new fast-food outlets in a 32-square-mile area of South L.A.
More than a dozen states and numerous cities are pondering legislation patterned after a new California law forcing chain restaurants to list calorie counts on their menus.
But blaming restaurants for the nation's weight problem strikes many as misguided. Obesity can be a product of a variety of factors, experts say, including genetics, lack of exercise and household nutrition. Courts have struck down patrons' attempts to sue restaurant chains for making them fat.
Not every group living or working in areas where fast food is plentiful experiences a higher incidence of obesity. The report's authors studied weight data for pregnant women, another group for which statistics are easily available. They found a much smaller correlation between the expectant mothers' weight gain and their proximity to the same type of burger, chicken and pizza restaurants.
The high schoolers studied appeared more susceptible to the temptations of fast food.
Researchers examined body-fat data taken from the mandatory fitness tests administered to all ninth-graders enrolled in California's public schools. Schools use a variety of methods, including skin-fold calipers. Using that device, a measure of more than 32% body fat for ninth-grade girls and more than 25% for boys is considered obese. The average is 25% for girls and 15% for boys, according to state guidelines.
The tests take place in the spring, giving the students about 30 weeks of exposure to the fast-food restaurants near their campuses before body-fat measures are recorded. The study looked at data from more than 1,000 public high schools. About 80 of them had a fast-food establishment within a tenth of a mile of their campuses, a large enough sample to make the findings valid, DellaVigna said.
Latino and female students were the most susceptible to weight gain, according to the study.
At Fullerton Union, students learn about nutrition in health classes, and the school tries to serve healthful fare, said Principal Catherine Gach. But the school has little control over what happens outside its gates.
Gach said freshmen aren't supposed to leave campus at lunch, but she admitted that some sneak out from time to time. Others stop by McDonald's before or after school.
The Oak Brook, Ill.-based fast-food giant declined to discuss the issues raised by the study, such as store location and teen obesity, saying only that it offers a variety of food choices.
Taco Bell, another chain mentioned in the study, said that its core market is males 18 to 34 and that it doesn't specifically target kids. The Irvine-based chain provides customers with nutritional information and a variety of low-fat offerings, said Rob Poetsch, a Taco Bell spokesman. It's also adding calorie information to its menu boards.
The finding that students who are constantly exposed to fast food are more likely to be fat "should not be a surprise," said Brenda Roche, a registered dietitian at UC Cooperative Extension in Los Angeles County.
"If you put a McDonald's in front of a school, kids will eat there," she said. "Obesity is as much a factor of environment as it is a matter of choice."
But there's hope for high school students hooked on burgers and fries, said Robert Hemedes, apartially reformed fast-food junkie.
"Now that I am older and I saw how it can impact the waistline, I no longer orderthe larger sizes and I make sure to exercise," said Hemedes, a human resources worker in Los Angeles. Last week he ate at McDonald's but limited his order to a regular hamburger and small fries. The $2.07 bill fit his budget, he said, "saving me money so I can go out with my foodie friends to a better restaurant on the weekend."
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