A new study reveals new evidence on what might work – and what might not – when it comes to food labelling.

 

Over the past two decades, labels such as the US Nutrition Facts Panel on packaged foods, calorie counts on national restaurant menus, front-of-pack labels encouraging healthier eating, and “low-sodium” or “fat-free” identifiers have been developed in order to promote healthier choices. But do they work?

 

A new Food-PRICE systematic review and meta-analysis of interventional studies – led by researchers from the Friedman School of Nutrition Science and Policy at Tufts University and recently published online in the American Journal of Preventive Medicine – assessed the effectiveness of multiple types of food labels. The researchers found that these approaches can impact some targets, but not others, for both consumer and industry behaviour. The 60 interventional studies reviewed were comprised of two million unique observations – including consumer reported dietary intakes, purchases and sales receipts – published from 1990–2014.

 

“Many old and new food policies focus on labelling, whether on food packages or restaurant menus. Remarkably, the effectiveness of these labels, whether for changing consumers’ choices or industry product formulations, has not been clear,” said senior and corresponding author Dariush Mozaffarian, M.D., Dr.P.H., Dean of the Friedman School, who added that the findings “provide new evidence on what might work, and what might not, when implementing food labelling”.

 

Informed choices

 

In a pooled analysis of studies that included food labelling on menus, product packaging, or other point-of-purchase materials such as placards on supermarket shelves, the researchers found that labelling reduced consumers’ intake of calories by 6.6 per cent and total fat by 10.6 per cent. It also reduced consumers’ intake of other unhealthy food options by 13 per cent.

 

Labelling also increased consumers’ vegetable consumption by 13.5 per cent.

 

In contrast, labelling did not significantly impact consumer intakes of other targets such as total carbohydrate, total protein, saturated fat, fruits, whole grains, or other healthy options.

 

When industry responses were evaluated, the researchers found that labelling led to reductions of both trans fat and sodium in packaged foods by 64.3 per cent and 8.9 per cent, respectively. However, no significant effects of labelling were identified for industry formulations of total calories, saturated fat, dietary fibre, other healthy components (e.g., protein and unsaturated fat), or other unhealthy components (e.g., total fat, sugar, and dietary cholesterol), although relatively few studies evaluated those endpoints.

 

“For industry responses, it’s interesting that the two altered components – trans fat and sodium – are additives,” said Mozaffarian. “This suggests that industry may be more readily able to alter additives, as opposed to naturally occurring ingredients such as fat or calories, in response to labelling. It will be interesting to see whether this will translate to added sugar, newly added to the Nutrition Facts Panel on food labels in the United States.”

 

Improving health outcomes

 

The researchers also examined the effects of label type, placement, and other characteristics. No consistent differential effects were found by label placements (menu, package, other point-of-purchase), label types (e.g., traffic light, nutrient content), type of labelled products, whether labelling was voluntary or mandatory, or several other factors. The researchers concluded that this suggests that the general presence or absence of information may be more relevant to consumers and industry than the specific type of label.

 

The study is part of the Food Policy Review and Intervention Cost-Effectiveness (Food-PRICE) research initiative, an NIH-funded collaboration of researchers led at Tufts University – the only independent school of nutrition in the United States – working to identify nutrition strategies that can have the greatest impact on improving health outcomes in the US.