Study: Fast-food ad ban needed

A little less “I’m Lovin’ It” could put a significant dent in the problem of childhood obesity, suggests a new study that attempts to measure the effect of TV fast-food ads.

A ban on such ads would reduce the number of obese young children by 18 percent and obese older kids by 14 percent, researchers found.

They also suggested that ending an advertising expense tax deduction for fast-food restaurants could mean a slight reduction in childhood obesity.

Some experts say it’s the first national study to show fast-food TV commercials have such a large effect on childhood obesity. A 2006 report suggested a link, but concluded proof was lacking.

“Our study provides evidence of that link,” said co-author Michael Grossman, an economics professor at City University of New York.

The percentage of U.S. children who are overweight or obese rose steadily from the 1980s until recently, when it leveled off. About a third of American kids are overweight or obese, according to Atlanta-based Centers for Disease Control and Prevention estimates.

The causes of childhood obesity are complicated, but for years researchers have been pondering the effects of TV ads. Separate studies have found fast-food commercials account for as much as 23 percent of the food-related ads kids see on TV, and have estimated children see fast-food commercials tens of thousands of times a year.

The new study is based in part on several years of government survey data from the late 1990s that involved in-person interviews with thousands of U.S. families. The researchers also looked at data on local stations in the 75 largest TV markets.

The researchers addressed other influences such as income and the number of nearby fast-food restaurants. They also took steps to account for the possibility that some children may already have been overweight and inactive regardless of their TV-watching habits.

The study is being published this month in the Journal of Law & Economics. The authors, funded by a federal grant, included Grossman and researchers from Lehigh University and Georgia State University.

The authors stopped short of advocating an advertising ban or eliminating the advertising tax deduction.