TV Ads Linked to Unhealthy Diets in Young Adults

Fast food and alcohol advertising on television have a negative influence on young people's weight and underage drinking, researchers affirmed in a survey.

Risk of obesity rose 3% with each fast food chain ad remembered or liked by 15- to 23-year-0lds (OR 1.03, 95% CI 1.01 to 1.04), Auden C. McClure, MD, MPH, of Dartmouth-Hitchcock Medical Center in Lebanon, N.H., and colleagues found.

Greater familiarity with alcohol ads also boosted the likelihood that teens had already started drinking and correlated with higher levels of intake in a second analysis by Susanne E. Tanski, MD, MPH, from the same group at Dartmouth.

Both were presented at the Pediatric Academic Societies meeting in Boston.

"These studies are showing that kids recognize advertising readily and it appears linked to risk behaviors," Tanski told MedPage Today.

With such broad exposure to advertising, pediatricians and parents need this kind of information to guide kids in making healthy choices, McClure noted in a press release.

The study surveyed a national sample of youth with phone and web-based assessments of advertising exposure.

The fast food analysis included 2,359 respondent, 15- to 23-year-olds, queried on a random subset of 20 ads (out of more than 500) from the top 25 fast food companies over the prior year.

They were shown images digitally edited to remove branding and then scored 1 point for recognizing having seen the ad, another point for liking it, and 2 points for identifying the brand.

The familiarity scores rose with weight status (P=0.003), with averages of:

21.4 for normal weight participants
22.3 for the 15.7% who were overweight
23.7 among the 13.6% of participants who were obese

The elevated risk of obesity with each 1-point higher ad recognition score were statistically significant after adjustment for age, race, gender, parent education, daily consumption of soda or other sweetened drinks, exercise, and snacking habits while watching TV.

Greater recognition of alcohol ads didn't correlate with obesity, suggesting that association was specific to food ads, the researchers concluded.

However, "because this is the first population survey to show such an association, replication is necessary, preferably with longitudinal data, in order to inform policy," the group cautioned.

The alcohol ad analysis determined how familiar underage participants (ages 15 to 20) in the survey were with nationally-televised ads aired over the prior year from the top beer and distilled alcohol companies.

The participants viewed 20 randomly selected ads with branding digitally removed and were similarly scored 1 point for having seen the ad, 1 for liking it, and 2 points for identifying the brand.