Salt alerts on menus push diners to choose lower-salt meals, research shows

The Impact of Salt Warning Labels on Consumer Choices

A recent study published in The Lancet Public Health has provided compelling evidence that salt warning labels on restaurant menus are effective in influencing consumer behavior. These labels not only help people make healthier choices but also increase awareness of the salt content in their meals and reduce the amount of salt ordered.

The research, led by Dr. Rebecca Evans from the University of Liverpool, is the first of its kind in the UK. It included both an online and a real-world randomized controlled trial (RCT), demonstrating the potential of menu labeling as a scalable public health strategy. The study’s findings suggest that such policies could play a crucial role in improving population health, given that excessive salt intake is a major contributor to diet-related diseases.

Key Findings from the Study

Salt warning labels used in the study were designed to identify items that exceed 50% of the recommended UK daily salt limit of 6g. These labels were tested in both hypothetical and real restaurant settings.

In an online RCT involving 2,391 UK adults, participants perceived the labels as effective in discouraging the selection of high-salt items. The study found that the labels reduced the amount of salt ordered by 0.26g per meal. In a real-world trial conducted at a Liverpool restaurant with 454 participants, similar results were observed. The labeled menus were perceived as effective in discouraging high-salt selections, prompted greater awareness of salt content, and reduced salt ordered by 0.54g per meal.

Across both trials, the effectiveness of the labels remained consistent regardless of age, sex, or education level. This suggests that the intervention could benefit all consumers and does not exacerbate health inequalities.

The Role of Nudges in Encouraging Healthier Choices

Dr. Evans emphasized that even small nudges at the point of purchase can encourage healthier decisions. "This study demonstrates that even small nudges at the point of purchase can encourage healthier choices," she said.

Sonia Pombo, Head of Impact and Research at Action on Salt, welcomed the findings, highlighting the importance of clear and visible salt warning labels on menus. She noted that excessive salt in out-of-home meals contributes to high blood pressure and preventable deaths. "If we're serious about protecting public health and saving lives, salt reduction must be front and center of the UK's food policy agenda," she added.

Public Support and Policy Implications

The study also revealed strong public support for implementing salt warning labels on menus. Approximately two-thirds of participants backed the idea as a government policy. Despite this, the UK currently lacks mandatory nutrient warning policies in restaurants, even though the government has committed to reducing salt intake and the World Health Organization recommends menu labeling.

Dr. Evans noted that the study provides UK-specific evidence that such policies are valued by consumers and help them make informed choices. "We hope to see government action to bring restaurant labeling in line with other national nutrition goals," she said.

Prof Eric Robinson highlighted the need for better regulation of the out-of-home food sector. "Businesses in the out-of-home food sector sell menu items which contain more than an entire day's worth of salt and consumers are left completely unaware," he said. "Governments need to better regulate the out-of-home food sector so that the food being provided to the public promotes rather than compromises health."

Collaborative Efforts and Future Directions

The study was a collaborative effort involving researchers from Liverpool John Moores University, Bath Spa University, and the University of California, Davis. Their contributions helped shape the study design, implementation, and analysis.

This research adds to growing international evidence that simple, cost-effective menu labeling interventions can support healthier food choices and reduce population-level salt intake. As the conversation around public health and nutrition continues, the findings from this study underscore the importance of policy changes that prioritize consumer well-being.