For the study
, researchers asked 2,381 parents to complete online surveys in which they selected a drink for their child from among 20 choices and answered questions about the healthiness of the beverages. Twelve beverages were considered sugar-sweetened because they had at least 75 calories from added sugars, and included sodas and juice drinks. The eight other drinks were water, juices and diet sodas.
Some of the parents in the study viewed images of their sugary drink options that had health warning labels on the front of the bottle. The labels were based on wording in a proposed bill in California that would require labels stating, "Drinking beverages with added sugar(s) contributes to obesity, diabetes and tooth decay." Other parents saw a calorie label on the front of the bottle, which beverage companies in the United States display on bottles and cans voluntarily. For yet another group of parents, the drinks did not display calorie or health warning labels.
The researchers found that parents were less likely to choose a sugary drink for their child if those drinks had health warning labels. Forty percent of the parents who saw those labels went with the sugary drink option, compared with 53% of the parents who saw the calorie label and 60% of those who were given no labels.
"We are trying to make a link between the high sugar content and the calories and the actual downstream outcomes [of sugary drinks]. You can say that something has 18 or 24 grams of sugar, but most people have no clue what a gram is," said David Hammond, professor in the school of public health at the University of Waterloo in Ontario.
"[Health warning labels] provide an extra layer of information that people can understand," added Hammond, who led the research, which was published on Thursday in the journal Pediatrics.
Bills are under consideration in New York and California that would require sugar-sweetened beverages to feature health warning labels on their packaging, similar to tobacco warning labels in the United States and many other countries. San Francisco has passed a law, which has not gone into effect yet, that requires advertisements for sugary drinks to include warning labels.
This study suggests labels may have the intended effect to reduce the consumption of sugary drinks, and may also give policy makers the impetus to pass these bills, Hammond said.
Changing parents' perceptions
The researchers focused on parents of children ages 6 to 11. There is particular concern about sugar consumption in young children because of the effects it could have on their health and nutrition, and the fact that it is training their palate from a young age to want sweets, Hammond said. It is important to look at how parents select foods for children in this age group because "the typical 6- or 7-year-old is not walking into a store and buying their own beverage," Hammond said.
The study found that health warning labels on sugary drinks dissuaded parents not only from selecting one of the drinks during the survey, but also made them say they were less likely to buy these drinks in the future. In addition, the parents who saw the labels were more likely than the other parents to say sugary drinks were not healthy, would not help their child focus or feel energized and increased the risk of weight gain, heart disease and diabetes.
The researchers found that the California health warning label, as well as three variations of the label, were similarly effective in terms of what parents selected and their perceptions. One of the variations used the term weight gain instead of obesity, another specified type 2 diabetes as a potential outcome as opposed to diabetes in general, and the third described all three outcomes as preventable.
The study also suggests that parents want the information on labels. Out of all the parents in the study, 73% said they supported a government policy that required health warning labels on sugary drinks. "[This] is encouraging for policy makers," Hammond said.
How labels could backfire
Sara Folta, assistant professor in the Friedman School of Nutrition Science and Policy at Tufts University, said she believes there is a need to explain to parents about the health harms of sugary drinks. "I think the issue is less about soda and more about sports drinks and other juice drinks that aren't 100% juice that parents perceive as maybe being healthy," said Folta, who was not involved in the study.
However, Folta worries there could be potential for health warning labels to backfire, particularly among adolescents who might find it enticing to consume something that is bad for them.
"This research is a promising first step but we need to study [labels in other age groups] before a major policy is unveiled that could have unintended negative consequences for particular segments of the population," Folta said.
Another way health label warnings could fall short is if they are less accessible to people with less education. The study included people with a range of education based on degree level, and did not see a difference in the effect of health warning labels. However, by finding people willing to complete online surveys, it's possible the study inadvertently included a subset of the population that is better at reading and carrying out tasks, Folta said.
The impact of health label warnings could also wane, just like tobacco warning labels, because people become desensitized to them, said Hammond, who has carried about research on the effect of tobacco warnings. Many countries around the world, but not the United States, have tweaked these warnings over the years, making them bigger, more colorful and more graphic to keep their effect from wearing off. The same might have to be done for sugary drink labels, Hammond said.