On-shelf nutrition labels help supermarket shoppers choose healthier foods

Providing an on-shelf nutrition labelling system in supermarkets has led to grocery shoppers making healthier food purchases, new research led by Public Health Ontario (PHO) has found.

Poor diet is a leading risk factor for chronic disease and premature death in Canada and in many other countries around the world, and healthy eating and informed food choices are a major focus in many jurisdictions. Health Canada is currently updating the Canada Food Guide, with guidelines expected to be released early next year, and is in the process of developing a mandatory front-of-package nutrition labelling system on packaged foods.

Dr. Erin Hobin, a scientist in PHO’s health promotion, chronic disease and injury prevention division, led a team of researchers examining whether an on-shelf nutrition labelling system (such as Guiding Stars, available at a major Canadian grocery retailer) had an influence on food purchases. The researchers conducted the study across three supermarket chains in Ontario (Loblaws, Zehrs and Real Canadian Superstore), one of which implemented the Guiding Stars system in 2012. They used aggregated supermarket purchase data to test the effect of Guiding Stars on food purchases between shoppers at the supermarket chains. Exit interviews of randomly selected shoppers were also conducted. In total, the researchers examined millions of transactions covering June 2012 to July 2013.

Guiding Stars is an on-shelf nutrition labelling system that uses ratings of zero to three stars, with zero stars given to foods with low nutritional content (products such as cookies, ice cream or potato chips) up to three stars for foods that are healthier (such as fresh fruits and vegetables, grains and milk, or fresh fish and meats). The intent of these labelling systems is to provide consumers with simple, standardized nutrition information to support more informed and healthier food choices.

“The study results show that the introduction of an on-shelf nutrition labelling system led to a small but significant increase in the proportion of food purchased in the supermarket with higher star ratings over a six-month period,” says Dr. Hobin. “We saw more items purchased with less trans fats and sugar and more fiber and omega-3 fatty acids. The results show that the introduction of a simple, standardized on-shelf nutrition rating system encourages shoppers to make positive shifts in their food purchasing behaviour.”

The researchers say they detected a positive effect of the Guiding Stars system even though only a modest proportion of shoppers say they were aware of the on-shelf labelling system. They saw some variation across food product categories, with the greatest benefits seen in categories that are perceived as healthier, like grains and breakfast cereals, dairy and eggs, fruit and vegetables, and meats, fish, and legumes. However, they also note that the majority of shoppers strongly supported this type of on-shelf rating system in supermarkets

“The results of this study suggest implementing a simple, at-a-glance nutritional summary of the product that is located on the front of food packages or on retail shelf tags may be a valuable intervention for supporting consumers in making more informed and nutritious food choices,” says Dr. Hobin. “The goal of these tools is to increase the proportion of shoppers who notice, understand, and use nutrition information to make healthier food choices for themselves and their families. Given this is the first study in Canada to investigate the effects of an on-shelf nutrition labelling system in actual supermarkets, results can inform current and future nutrition labelling policies in Canada and globally, and provide critical information to policy makers who might be developing and mandating a simplified nutrition labelling system to support consumers in that effort.”

Dr. Hobin conducted the research with fellow scientists from PHO, Duke University, the University of Toronto, and the University of Waterloo. The study is published in the September issue of Milbank Quarterly.