As California lawmakers consider legislation that would require "high sugar" warning labels on restaurant menus, a University of California, Davis, study shows that the labels are effective in dissuading diners from ordering sugary items.
Researchers tested menus with added-sugar warning labels against unlabeled menus in an online study with more than 10,000 people nationwide during six weeks in 2024-25. Compared to no label, diners ordered on average more than 10 grams less added sugar when they saw triangle icon containing a spoon and exclamation point with explanatory text. Additionally, a noticeable, easy-to-see, icon-only label also caused people in the study to reduce the added sugar in meals they ordered by almost 7 grams.
"This is a substantial amount, as the daily recommended limit for added sugars is 50 grams," said Jennifer Falbe , a professor of human development and family studies in the Department of Human Ecology at UC Davis.
"For someone eating restaurant foods five times a week, this could result in 50 fewer grams of added sugar, or 200 fewer calories from sugar, a week, which adds up to 2,600 fewer grams of added sugar a year," added Falbe, the study's senior author.
The study was published in the June issue of Lancet Public Health.
This study is the first to quantify the effects of "added-sugar" warning labels on menus. The study looked at how these labels, which were designed for noticeability and comprehension, influenced consumers' food orders from menus at full-service and fast-food restaurants, researchers said.
The labels
In this study, researchers looked at an icon-plus-text label and a taller, red icon-only label.
The most effective label turned out to be a black, icon-plus-text label displayed at menu item text height, researchers said. This icon-plus-text label featured a spoon and exclamation mark as well as words in capital letters, "SUGAR WARNING." The warning labels were placed next to items high in added sugars.
The study also tested two added-sugar thresholds for applying the labels: 50% of the daily recommended limit per serving, which has been proposed in California, and 100%, which is already used in New York City .
"Although we did not find differences by label threshold on the few menus we tested, the 50% threshold that the California legislature is considering may end up being more effective because it would incentivize restaurants to reformulate more menu items to contain less sugar," said the study's lead author, Yuru Huang, assistant professor at the University of Tennessee Health Science Center and postdoctoral scholar at UC Davis when working on the study.
California's SB 869, which has passed the state Senate and is now pending in the Assembly, would require warning icons for menu items high in added sugar.
"Mandating noticeable added-sugar warning labels for restaurant menus is a promising policy option for reducing added sugar ordered from restaurants and improving public health," said Falbe.
Additional authors of the study included Brittany Lemmon, Graduate Group in Epidemiology, UC Davis, and others.
Funding was provided by the American Diabetes Association and Bloomberg Philanthropies.
