Warnings suggested on sugary drinks packaging

Plain packaging and warning labels may help reduce consumption of sugary drinks by young people, according to research from the University of Auckland.

In a world-first study to examine the effects of plain packaging and warning labels on young people's predicted preferences for sugary drinks, the online experiment suggests these reduce young people's demand for the drinks.

The study also examined the effect of taxes on sugary drink preferences for young people.

The research was led by Professor Cliona Ni Mhurchu from the University's National Institute for Health Innovation, and was published today by the International Journal of Behavioral Nutrition and Physical Activity.

"Plain packaging had the most significant negative impact on young people's product preferences," says Professor Ni Mhurchu. "It was also associated with less positive perceptions of those who might consume the product."

"These results align with findings from studies of plain packaging for tobacco products," she says.

The placement of a warning label on the sugary drinks also had a significant negative impact on young people's predicted preferences.

A text-only warning on the label, recently adopted in San Francisco as a public health policy to reduce intake of sugary drinks, reduced perceived product attractiveness, quality and taste, and reduced perceptions of consumer "coolness".

Similar research examining how warning labels on sugary drinks influenced parents' choices found they improved parents' understanding of health harms associated with over-consumption of these drinks and reduced intentions to purchase sugary drinks for their children.

"Although graphic warning labels have not yet been proposed for sugary drinks, this research suggests they would be more effective than text warning labels," says co-investigator and tobacco control researcher, Associate Professor Natalie Walker.

"We found that warning labels had a greater effect when placed on beverages with plain packaging compared with branded packaging," she says. "This suggests that attractive branding and colours on sugary drinks may reduce the effectiveness of warning labels.

"These results are again consistent with tobacco research."

The study authors say that given the success of tobacco taxes in reducing consumption and emerging evidence of behavioural effects of sugary drink taxes, their finding in this study of only a weak effect from a 20 percent tax, was unexpected.

"It is possible that this was due to how taxes were used in this study where price was displayed in text below the sugary drink image, rather than on a more prominent price label such as those used in supermarkets or convenience stores," says Professor Ni Mhurchu.

"The price information may not have been sufficiently obvious and the absence of comparatively priced products may have limited our study participants' ability to judge the relative cost of the products," she says.

"Our finding may also reflect the relative importance of price and branding to young people."

"Brand image and social recognition have a powerful influence on adolescents' preferences and decision making," says Professor Ni Mhurchu. "Plain packaging and warning labels could therefore be effective ways to reduce young people's intake of sugary drinks and prevent childhood obesity."