Increased control? Visible calorie content may alter how desirable foods appear to consumers

03 Jan 2019 --- Foods appear to become less desirable when their calorie content is visible, a Dartmouth College study has found. Among participants, seeing pictures of food with calorie information not only made food less desirable, but it also appeared to change the way the brain responded to the food. Making calorie information available alongside food, via menus, for example, has been on the obesity-fighting agenda for a number of countries, including the UK and the US.

Published in PLOS ONE, the study noted that among participants, the brain displayed decreased activation of the reward system when calorie content appeared alongside images of food and increased activation in the control system.

“Our findings suggest that calorie-labeling may alter responses in the brain's reward system when considering food options. Moreover, we believe that nutritional interventions are likely to be more successful if they take into account the motivation of the consumer, including whether or not they diet,” says first author Andrea Courtney, a postdoctoral student at the Stanford Social Neuroscience Lab at Stanford University.

In the study, 42 undergraduate students viewed 180 fSeeing pictures of food with calorie information not only made food less desirable, but it also appeared to change the way the brain responded to the food.ood images without calorie information followed by images with calorie information and were asked to rate their desire to eat the food while in a functional magnetic resonance imaging scanner (fMRI).

While dieters and non-dieters alike rated calorie-labeled foods as less appetizing, this effect was strongest among dieters. Furthermore, the researchers analyzed responses in two brain regions that motivate eating behavior: the nucleus accumbens (NAcc) and the orbitofrontal cortex (OFC).

Although all participants showed a decrease in activation in these areas when calorie information was present, dieters showed more similar activation patterns in the left OFC for calorie-labeled and unlabeled foods. This finding suggests that dieters may consider calorie information even when it isn't explicitly present and builds on previous research suggesting that the presence of health cues can lead to healthier food decisions.

“In order to motivate people to make healthier food choices, policy changes are needed that incorporate not only nutritional information, including calorie content but also a public education component, which reinforces the long-term benefits of a healthy diet,” adds senior author Kristina Rapuano.

The study is the first of its kind to examine how your brain makes food choices when calorie information is presented, the authors note. 

The results are timely given that earlier this year, certain food chain establishments had to comply with the US Food & Drug Administration's (FDA) menu labeling law requiring the disclosure of calorie information on menus and menu boards. In addition, according to the Centers for Disease Control and Prevention, obesity affected nearly 40 percent of US adults in 2015-16. 

Although the idea behind the new rules is to help US consumers make informed decisions about the foods they eat, there is still debate around whether menu labeling will benefit their health. 

In the Journal of Public Policy & Marketing, for example, researchers from New York University have noted that despite the rapid and widespread adoption of policies to require calorie counts at restaurants, most studies of calorie labels in fast-food restaurants in places that have already adopted labeling, including New York, have found little evidence that fast-food consumers are changing their behaviors in response to menu labels. 

On the other hand, research from the Perelman School of Medicine at the University of Pennsylvania suggested in 2016 that adding color-coded or numeric calorie labels to online food ordering systems can help reduce the total calories ordered by about 10 percent when compared to menus featuring no calorie information at all. 

In the UK, a Diabetes UK poll found that three-quarters of the public would like to see all cafes, restaurants and takeaway outlets display calorie information on their menus. According to a University of Liverpool study, the government is currently consulting on a plan to introduce mandatory labeling in restaurants, takeaways and cafes, which is likely to finish later this year.

By Laxmi Haigh