People will choose larger portions of food if they are labelled as being healthier, even if they contain the same number of calories, according to a new study.
People think healthier food is lower in calories
“People think healthier food is lower in calories,” said Pierre Chandon, a marketing professor at the Insead Social Science Research Centre in France, and they “tend to consume more of it”.
That misconception can lead to people eating larger portion sizes of so-called healthy foods, and therefore more calories.
“Foods are marketed as being healthier for a reason, because food producers believe, and they correctly do so, that those labels will influence us to eat their products and perhaps eat more of them,” said Cliodhna Foley Nolan, director of Human Health and Nutrition at Safefood, a government agency in Ireland.
Safefood commissioned the study, led by Barbara Livingstone, a professor at the University of Ulster.
Dr Foley Nolan said the portion sizes of food had become larger over the years, and Safefood wanted to see whether health and nutrition claims had any influence.
The researchers asked 186 adults to assess the appropriate portion sizes of foods.
Given a bowl of coleslaw, the participants served themselves more of the coleslaw labelled ‘healthier’ than the coleslaw labelled ‘standard’.
For instance, obese men served themselves 103 g of healthy coleslaw and 86 g of standard coleslaw.
In reality, the healthy-labelled coleslaw had just as many calories – 941 kJ (or 224 calories) for every 100 g – as the ‘standard’ coleslaw, which had 937 kJ (or 223 calories).
Additionally, people tended to underestimate how many calories were in a serving for the ‘healthier’ coleslaw.
The participants most often thought the ‘healthier’ coleslaw contained 477 kJ, or 113 calories.
In contrast, they were not far off in estimating the calories in the ‘standard’ coleslaw.
Prof. Chandon, who was not part of this study, said people tended to stereotype food that could be healthy in one aspect, say, lower in fat, as being healthy in every dimension.
But in fact, food labelled as being healthy is not always lower in calories.
He said one reason why people might overeat healthier foods is because they feel less guilty when they choose a healthier option.