How food labels can help tackle climate change

Empty shelves as retailers remove chicken sandwiches following concerns about a salmonella outbreak (Getty Images)
Empty shelves as retailers remove chicken sandwiches following concerns about a salmonella outbreak (Getty Images)

Climate change labels would persuade us to choose more sustainable food, according to a new study.

Sticking a “high climate impact” label on a burger made 23 percent more people choose a red-meat-free option.

John Hopkins University gave over 5,000 people a sample fast food menu and asked them to pick an item for dinner.

One group received a menu where options without red meat were positively labelled “low climate impact”, and included a chicken sandwich, salad, and fish.

Another had a menu with red meat burgers negatively labelled “high climate impact.”

Menus provided to the third group had QR codes on all items and no climate labels.

High and low climate labels drastically reduced the amount of people choosing red meat, versus the control group.

Negative labels describing the “high climate impact” of red meat had the strongest effect, deterring 23 percent more people from eating red meat.

Menus featuring “low climate impact” labels led 10 percent more people to pick a chicken sandwiches, salad or fish than the control.

Lead author Dr Julia Wolfson, associate professor in the Department of International Health at the Bloomberg School of Public Health, said: “These results suggest that menu labeling, particularly labels warning that an item has high climate impact, can be an effective strategy for encouraging more sustainable food choices in a fast food setting.”

Writing in JAMA Network Open, she said their findings show the positive framing of “low climate impact” was less effective in encouraging sustainable food choices, than the more negative labelling.

Participants were asked to choose an item for dinner, and then rate how healthy they thought the item was.

Those who selected a more sustainable option perceived their choice to be healthier than those who stuck with red meat.

Signposting menus with climate information is a potential approach for promoting sustainable food choices, such as avoiding red meat.

They added climate labels could have the unwanted side effect of making a choice appear healthier than it really is.

The meat is also the largest source of greenhouse gas emissions in the food and agriculture sector.

Among other illnesses, its consumption is linked to colorectal cancer, stroke, and type 2 diabetes.

Researchers used an index to measure how healthy food is on a 100-point scale, with 64 and lower considered healthy.

They found those using the menu with “high climate impact” labels choose slightly healthier options than the “low climate impact” cohort.

However, none of the items on the menu scored well enough to be optimally healthy.

Dr Wolfson said: “An undeserved health halo conferred to unhealthy menu items could encourage their overconsumption so we have to look for labeling strategies that create ‘win-wins’ for promoting both more sustainable and healthy choices.”

She plans to do similar studies in real-world settings.