The research team, led by scientists from UCL, Bath Spa University, the University of Cambridge and the University of Oxford, examined evidence from 25 studies on the impact of calorie labelling on food selection and consumption. The average reduction was 1.8%, which would equate to 11 calories in a 600 calorie meal.
A UK Government report estimated that 90% of 20-40 year-olds in England will gain up to 9kg over ten years, and that reducing daily energy intake by 24 calories per day, which is roughly 1% of the recommended intake for adults, would prevent this increase.
Dr Gareth Hollands, senior author from the UCL Social Research Institute, commented: “Our review suggests that calorie labelling leads to a modest reduction in the calories people purchase and consume. This may have some impact on health at the population level, but calorie labelling is certainly no silver bullet.
“Our previous version of this review from 2018 reported a potentially larger effect, but was inconclusive because there was significant uncertainty over the results. This update has reduced that uncertainty, and we can now say with confidence that there is very likely a real, albeit modest, effect.”