Health and Medicine

Picture warnings reduce purchases of sugary drinks for children

Carolina research suggests warning labels on juice and soda could be a new tool in the fight against childhood obesity

Children in the United States and many other countries consume more than the recommended amount of sugary drinks, but a Carolina study suggests warning labels may reduce purchases.

(CHAPEL HILL, N.C.) A study published Feb. 1 in the journal PLOS Medicine is the first to examine in a realistic setting whether pictorial health warnings on sugary drinks — like juice and soda — influence which beverages parents buy for their children.

The findings are promising: The warnings reduced parental purchases of sugary drinks for their kids by 17%.

Researchers at the University of North Carolina at Chapel Hill Gillings School of Global Public Health conducted the study in a unique laboratory — the “UNC Mini Mart.” The space models a convenience store shopping experience.

Study authors Lindsey Smith Taillie and Marissa G. Hall

“We created this store because we saw a major need for research that tests the impact of policies in a food store setting that is much more realistic,” said senior author Lindsey Smith Taillie, assistant professor in the UNC Gillings Department of Nutrition and a member of the UNC Carolina Population Center (CPC). “When people make choices about what food to buy, they are juggling dozens of factors like taste, cost and advertising and are looking at many products at once.

“Showing that warnings can cut through the noise of everything else that’s happening in a food store is powerful evidence that they would help reduce sugary drink purchases in the real world,” Taillie said.

Study co-authors include lead author Marissa G. Hall, assistant professor in the UNC Gillings Department of Health Behavior and a member of the CPC and UNC Lineberger Comprehensive Cancer Center (LCCC), and Anna H. Grummon, PhD, an alumna of the UNC Gillings Department of Health Behavior who is now a David. E. Bell Fellow at Harvard University.

Researchers from the Gillings School of Global Public Health created the UNC Mini Mart to examine how various obesity-prevention policies work in a realistic setting.

The positive findings about the effects of image-based warning labels highlight a recent but increasingly common approach to combating the global struggle with obesity.

Children in the United States and many other countries consume more than the recommended amount of sugary drinks, which increases their risk for obesity and diet-related chronic diseases, including Type 2 diabetes and heart conditions.

There also are pronounced disparities by race/ethnicity, with higher rates of sugary drink consumption and obesity among Black and Latino children compared to non-Latino white children, in part due to structural factors like targeted marketing.

WATCH Transforming a lab into a mini mart 

Taillie has conducted research into warning labels and taxes on sugar-sweetened beverages and junk food in Chile, Mexico and South Africa. Hall researches the impact of warnings on tobacco and food products.

In their latest study, 325 parents of children aged 2-12 were randomly assigned to two different groups and asked to choose a drink and a snack for their child plus a household item in the store laboratory. The intervention group had pictorial health warnings about Type 2 diabetes  or heart disease displayed on drinks, while a control group had regular barcode labels.

Participants were instructed to choose one drink and one snack for their child, along with one household good; this shopping list was designed to mask the purpose of the study. After shopping, participants completed a survey about their selections and left with their drink of choice and a cash incentive.

The picture warnings led to a 17% reduction in purchases of sugary drinks, with 45% of parents in the control arm buying a sugary drink for their child compared to 28% in the pictorial warning arm.

The picture warnings also reduced calories purchased from sugary drinks and led to parents feeling more in control of healthy eating decisions and thinking more about the harms of sugary drinks.

The benefits of the picture warnings were similar for parents with different characteristics, including race, ethnicity and socioeconomic status, suggesting picture warnings could be effective across diverse populations. Larger studies are needed, however, to see how well warnings work for the groups at highest risk of diet-related disease.

“We think the paper could be useful for policymakers in the U.S. and globally,” Hall says. “This evidence supports strong front-of-package warnings to reduce children’s sugary drink consumption.”

Additional UNC-Chapel Hill authors include Isabella C. A. Higgins, a doctoral student in the UNC Gillings Department of Health Behavior and trainee at the CPC; Allison J. Lazard, PhD, E. Reese Felts Jr. Distinguished Associate Professor at the UNC Hussman School of Journalism and Media and a member of the Lineberger Comprehensive Cancer Center; Carmen E. Prestemon, a project coordinator at the CPC and Mirian I. Avendaño-Galdamez, a research assistant at the CPC.