Key messages
– Current evidence suggests that calorie (energy) labelling on menus, and on or next to products, leads to reductions in calories selected and bought from food and non-alcoholic drinks. The evidence for consumption (eating) suggests a similar effect, but there is less evidence and it is of lower quality.
– There is insufficient evidence to estimate the effect of calorie labelling for alcoholic drinks.
– Calorie labelling of food could lead to potentially meaningful impacts on population health when applied at scale, but we need more high-quality studies for consumption and for alcohol products.
Why put calorie labels on products?
Overconsumption of food and consumption of any alcohol products are important causes of poor health. Labelling menus and the packaging of products to show how much energy they contain ('calories', which is measured in kilocalories), may reduce the amount that people buy and consume, and help them choose healthier options.
What did we want to find out?
We investigated whether adding calorie labelling to food (including non-alcoholic drinks) and alcoholic drinks changes people's selection and consumption of those products.
What did we do?
We searched for studies comparing the effects of labelling products versus not labelling products on the selection and consumption of food and drinks in people of any age. We compared and summarised the results, and rated our confidence in the evidence, based on factors such as study methods and sizes.
What did we find?
We found 25 studies, all of which were conducted in high-income countries. Twenty-three studies involved food, while two studies involved food and alcohol products. Most of these studies were conducted in real-world settings such as restaurants or supermarkets.
Main results
We found that adding calorie labelling to food reduced the amount of calories selected by a small amount (16 studies, 9850 people). For example, if there was no labelling, people would select a meal that had 600 kilocalories but, when there was labelling, they would select a meal that had 589 kilocalories (11 kilocalories fewer).
Calorie labelling on food may reduce energy consumed (8 studies, 2134 people). For example, if there was no labelling, people would eat a meal that had 600 kilocalories but, when there was labelling, they would eat a meal that had 565 kilocalories (35 kilocalories fewer).
There was insufficient evidence to assess the effects of calorie labelling on alcohol products (selection of calories: 2 studies, 5756 people; selection of alcohol: 1 study, 205 people).
What are the limitations of the evidence?
We are confident in the results concerning calorie labelling on selection and purchasing of food (including non-alcoholic drinks). In contrast, we have little confidence in the results concerning calorie labelling on consumption of food (including non-alcoholic drinks) because most studies were conducted in laboratory settings for short periods and not all the studies provided enough information about how they were conducted. We are not confident in our estimates of the effects of calorie labelling on alcohol products because there were not enough studies.
How up to date is this evidence?
This review is up to date to 2 August 2021.