To reduce obesity, cities across the United States have created public service ad campaigns to persuade teenagers to cut back on sugary drinks like soda. But do the ads work?
A new study published in the Journal of Health Communication is the first to test the effect of persuasive strategies used in public service ad campaigns aimed at sugar-sweetened beverages, which include non-diet soda, sports and energy drinks, sweetened teas and fruit drinks.
The researchers found that public service advertisements (PSAs) appealing to fear – and warning of the health consequences of too much sugar, such as obesity, diabetes, amputations, cancer and heart disease – had the greatest effect on teens’ intention to cut back on sugary drinks. The study also examined ads that appealed to humor and to nurturance (protective, parental instincts).
“We wanted to find out what types of persuasive strategies worked with PSAs designed to reduce the amount of sugary beverages that teenagers drink,” said lead author Amy Bleakley, a senior research scientist at the Annenberg Public Policy Center of the University of Pennsylvania who conducted the study with other Penn researchers. “With the ads we tested, fear-based messages produced a significantly higher intention among teens to cut back on sugary drinks.”
The fear-based ads worked directly to influence the adolescents’ intentions, as well as indirectly by affecting the perceived strength of the message. All three kinds of emotional appeals – fear, humor and nurturance – affected other emotions and cognitions as well, but not all of those were shown to be related to teens’ intention to cut back on sugary drinks.
Researchers used an experimental design to examine the effects of six ads – two each using humor, fear, or nurturance – as well as control ads on a national sample of 805 13- to 17-year-olds in 2012. The adolescents were divided into four groups. Each group saw ads using a different emotional approach or the control ads. The teens then were questioned about their intention to cut back, an approach which the study said is used as a consistent and effective proxy for behavior.
In 2010 the Centers for Disease Control and Prevention funded an initiative to address obesity and tobacco use, the leading preventable causes of morbidity and mortality in the United States. More than 50 communities received funding, and many of them created PSAs about the harmful effects of sugary beverages.
The PSAs on sugar-sweetened beverages follow prior PSA campaigns against tobacco, drugs and drinking and driving. While those other campaigns had been studied, this study said, “It is unknown how health messages about a widely accepted and advertised product will be perceived by teen audiences.”
In addition to Bleakley, other researchers on the study included Amy Jordan and Michael Hennessy of the Annenberg Public Policy Center; Karen Glanz and Andrew Strasser of the Perelman School of Medicine; and Sarah Vaala, former with APPC and now at the Vanderbilt University School of Nursing.