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.

Among the 51% who said they had ever had alcohol, 40% reported binge drinking in the prior year.

Alcohol ad familiarity rose across these categories, from mean scores of 10.6 among never-drinkers to 12.4 for ever-drinkers and 15.7 among binge drinkers.

Each 5-point increase in the ad recognition score was associated with 23% higher likelihood of having started drinking (adjusted OR 1.23, 95% CI 1.1 to 1.3). It also was linked to more intense alcohol use among underage drinkers (adjusted OR 1.11, 95% CI 1.0 to 1.2).

More familiarity with fast food ads didn’t predict more alcohol use, though, suggesting that the marketing content of the alcohol ads was responsible for its association with underage drinking, the researchers concluded.

“At present there is a voluntary standard for the alcohol industry,” Tanski said, explaining that it uses the so-called 30% rule to only run ads when 70% of the audience is expected to be adults.

“What we’re showing is that we have an enormous penetration of young people recognizing alcohol ads,” she added in the interview. “Perhaps their rule may need to be a little bit stronger if they’re trying to keep underage you from seeing their advertising.”

But she cautioned that the study couldn’t determine causality, as the reverse may have been true if those most likely to drink were most tuned-in to alcohol ads.

Primary source: Pediatric Academic Societies
Source reference: Tanski SE, et al. “Alcohol marketing and underage drinking behavior” PAS 2012; Abstract 2740.6.

Additional source: Pediatric Academic Societies
Source reference: McClure AC, et al. “Fast food ad recognition-recall and obesity in youth” PAS 2012; Abstract 2740.1.