Graphic warning labels keep buyers away from sugar-sweetened drinks

Warning labels, particularly those that depict graphic health effects, are effective in dissuading consumers from purchasing sugar-sweetened beverages (SSBs), reports a new meta-analysis.

“In comparison with the no-label control group, the use of SSB warning labels was associated with a 51-percent reduction in the odds of choosing SSBs,” the researchers said. “Across the alternative forms of SSB warning labels, graphic with health effect (GHE), text of health effect (THE), graphic with nutrient profile (GNP), and symbol with health effect (SHE) labels may have the potential to reduce SSB consumption.”

Drawing from the databases of the Cochrane Library, PubMed, Web of Science, CINAHL, Google Scholar, and Scopus, the researchers retrieved 23 studies eligible for meta-analysis. Aside from GHE, THE, GNP, and SHE, the included papers also looked at two more classes of labels: symbol with nutrient profile (SNP) and text of nutrient profile (TNP). Thirteen studies were randomized controlled trials. [Am J Prev Med 2021;60:115-126]

Twenty-one studies compared the effect of warning labels with a no-label control. Pooled analysis showed that these labels discouraged consumers from choosing SSBs, reducing the likelihood by more than half (odds ratio [OR], 0.49, 95 percent confidence interval [CI], 0.41–0.56).

The labels also significantly attenuated their SSB purchase intentions (Cohen’s d, –0.18, 95 percent CI, –0.31 to –0.06).

Comparisons between and among different labels were carried out in only eight studies. These found that of all the different classes, GHE labels had the strongest effect, cutting the odds of choosing SSBs by almost 70 percent (OR, 0.34, 95 percent CI, 0.08–0.61).

GHEs were followed by THE (OR, 0.47, 95 percent CI, 0.39–0.55), GNP (OR, 0.58, 95 percent CI, 0.36–0.81), and SHE (OR, 0.67, 95 percent CI, 0.39–0.95) labels. No significant impact on SSB patterns was reported for SNP and TNP labels.

“Graphic warning labels may be more likely to be noticed by a consumer, which highlights the importance of salience in engaging consumers’ attention,” the researchers said, pointing out that as in tobacco products, “graphic warning labels might trigger a spontaneous negative response against the product that dissuades consumers.”

There also seemed to be a more dissuasive effect of disclosing health effects, as seen in the significant impacts of SHE and THE labels, as opposed to simply stating nutrient profiles.  

Nevertheless, several study limitations deserve attention, the researchers said. These include the diverse study designs, shortage of sociodemographic information available, and subjective measurements of purchasing behaviour, rather than direct observations in a naturalistic environment.

“Future studies are warranted to delineate the psychosocial pathways linking SSB warning labels to purchase decisions, understand the differential impact on socioeconomically diverse populations, differentiate individual consumption patterns from household purchases, and examine the influence of SSB warning labels in naturalistic settings,” they added.