Obese people enjoy food less, say researchers

Previous experiments in laboratory conditions have shown that obese people feel less of a reward from food compared with ‘lean’ people but the researchers from Bangor University in Wales wanted to see if this is also the case when people eat in normal conditions as part of their everyday lives.

They therefore created an app that allowed individuals to rate and record their reactions to food and eating throughout the day.

In order to understand the participants’ perception of food and implicit and explicit attitudes towards eating, the researchers also questioned people on the extent to which they expected to feel relieved after eating, how guilty they felt after giving into cravings and if they felt a lack of control over eating in general.  

The data collected from the app showed several similarities between the obese and lean sets. Both groups, for instance, reported almost the same amount of food-wanting events per day – an average of five for the obese group compared to six for the healthy weight group.

Both groups also resisted around of 30% ‘food-wanting events’ and spent around the same amount of time – around 18 minutes – eating a meal.

Finally, the intensity of wanting food was not significantly different between groups, showing that obese people do not have more frequent or intense food-wanting experiences than lean people.

The key difference, however, was in the reported enjoyment of food: obese participants reported significantly less intense food liking than healthy weight participants.

Emotional motivations to eat

Writing in The Conversation​​​, director of the health exercise and rehabilitation group at Bangor University and author of the study Hans-Peter Kubis explained the findings.

“In the healthy weight group, the intensity of wanting food when people resisted temptation was less than when wanting was followed by eating, as one might expect. And the scores for liking were high after eating. ​

“This suggests that, in people with healthy weights, the decision to eat or not to eat is based on the intensity of wanting, and that food enjoyment supported the decision to eat.​

“This pattern, however, was not seen in the obese group. Their decision to eat, or not, didn’t seem to be driven by conscious wanting intensity, and their food satisfaction did not support their decision to eat. Emotional motivation in connection with cravings seems to be more influential in eating decisions in obese people than in healthy weight people."​

Kubis said the study is important in demonstrating the reward deficiency in daily life.

“We are exposed to food cues many times a day, particularly cues for highly palatable foods high in sugar and fat. A lot of our eating is based on reward, not hunger. Some brain imaging studies have suggested that obese people respond more to food cues, but may respond less to food consumption. ​

“A lack of reward could contribute to overeating, as it could result in a greater quantity of food being eaten in an attempt to compensate for the lack of enjoyment. To help people manage their weight, more attention needs to be paid to the reward value of eating.” ​

Source: Eating Behaviors​

“Ecological momentary assessment of food perceptions and eating behaviour using a novel phone application in adults with or without obesity”​

Published online ahead of print, 12 May 2018, doi.org/10.1016/j.eatbeh.2018.05.007​​

Authors: Kholoud Alabduljader, Marion Cliffe, Francesco Sartor, Gabriele Papinid, Miles Cox, Hans-Peter Kubis