Roberto et al. Pediatrics. 2016;137(2):e20153185.
Consumption of sugary drinks among children remains high, with two thirds of children aged 2 to 11 years old drinking them at least once a day. One untested strategy to reduce consumption is to place a warning label on sugary drink containers, soda fountains, or vending machines to provide parents with information about the health effects of sugary drinks. Roberto and colleagues find that such warning labels may reduce parents’ intent to purchase sugary drinks.
The researchers conducted an online, randomized controlled trial with 2,381 parents to assess the effects of beverage warning labels on their purchasing behavior and perceptions of different drinks. Parents were randomly assigned into either a control group (no information), a group presented with labels displaying calorie content but no health warning, or a group that saw health warning labels. Parents in each group were shown 20 beverages (12 of which were sugary drinks) and asked to choose one for their youngest child. Those assigned to a warning label group were told that “drinks with a lot of added sugar have a safety warning label on them” and then were shown a magnified label above an image of the product. The labels stated: “SAFETY WARNING: Drinking beverages with added sugar(s) contributes to obesity, diabetes, and tooth decay” or variants on this wording.
The parents who saw warning labels were significantly less likely to choose a sugary drink (40.4% in the warning label group vs. 59.9% in the no information control group, p < .001, and 53.3% in the calorie label group, p < .001). Providing calorie information did not reduce parents’ choice of sugary drinks relative to the control condition.
Limitations: The study design did not permit the assessment of actual purchases or consumption. Real world effects are likely to be smaller given the study provided a priming statement displayed before the actual warning label and magnified the label; the absence of pressure from children asking for sugary drinks, and the artificial testing context. Most sugary drinks are purchased in grocery stores while the hypothetical setting of this study was a vending machine. Online study participants are likely not representative of the general population, somewhat limiting the generalizability of the findings.
Implications: Policy makers should consider implementing and rigorously evaluating warning labels.