Do warning labels help people choose healthier drinks?

Warning labels on sugary drinks lead to healthier drink choices, according to new analysis of more than 20 studies examining these warnings. The new findings could help inform policymakers, who are increasingly interested in implementing policies requiring warning labels for sugar-sweetened beverages. Sugary drinks (also known as sugar sweetened beverages) refer to beverages with added sugar or other sweeteners, such as soda, sports drinks or fruit-flavored drinks.

"Our findings suggest that sugary drink warnings help consumers better understand products' healthfulness and encourage consumers to make healthier choices about what drinks to buy," said research team leader Anna H. Grummon, Ph.D., a David E. Bell Postdoctoral Fellow at Harvard T.H. Chan School of Public Health. "These results highlight the potential usefulness of sugary drink warning policies in both informing consumers and reducing consumption of unhealthy beverages like sodas, energy drinks and fruit-flavored drinks."

Grummon will present the research as part of Nutrition 2020 Live Online, a virtual conference hosted by the American Society for Nutrition (ASN).

"As policymakers' interest in this policy has grown, so too has research on sugary drink warnings," said the study's co-author Marissa G. Hall, Ph.D., assistant professor at the University of North Carolina in Chapel Hill. "However, skeptics worry that warnings won't be effective at informing consumers or encouraging healthier choices, and no research had synthesized existing evidence on sugary drink warnings to address these questions."

To fill this knowledge gap, the researchers identified 23 experimental studies of sugary drink warnings with data from 16,241 individuals. They then applied meta-analysis, a statistical technique that combines results from many studies. This approach allowed the researchers to create a detailed and comprehensive picture of existing research on sugary drink warnings. The meta-analysis indicated that, on average across studies, sugary drink warnings led to statistically significant reductions in sugary drink purchases.

"It is clear that sugary drink warnings can help consumers make healthier choices about the drinks they buy," said Grummon. "Now, we are studying the best ways to design warnings to maximize their benefits. For example, should warnings include icons or pictures that help communicate the warnings' message?"

The researchers are also exploring the effects of other types of messages to encourage healthier diets, for example, messages that encourage people to drink more water.