Harder dieting may backfire and lead to bingeing, suggests new study

A new study suggests that prolonged dietary restraint while hungry may provoke a rebound effect with binge-eating episodes when feeling full.
These findings provide new clues as to why extreme diets may be susceptible to fail as well as insights to inform better diet strategies for unsuccessful obese dieters looking to lower their risk of type 2 diabetes.
Researchers from the University of Vermont, in the US, have conducted an experiment on rats to try and understand why dieters might ‘relapse’ to eating, or overeating when satiated.
First the rats were conditioned to learn that if they pressed a lever in the box they were i, they’d receive treats ad-libitum. Over the next four days, they no longer had access to treats and were put in an effective state of prolonged calorie restriction.
After the dieting phase ended and the rats were transferred back in the box with the functional lever, researchers noticed that they pressed it far more often if they were full than if they were hungry.
What happened was that rats that learned to respond for treats while they were full and then inhibited their behaviour while hungry, tended to relapse when they were full again.
In other words, there was a marked tendency to overeat in response to stimuli like being presented with palatable foods after a period of restriction of food intake to prevent weight gain or promote weight loss.
Researchers believe seeking food and not seeking food are behaviours that are specific to the context in which they are learned. Here, the rats learned to associate satiety with receiving treats and hunger with receiving no food.
Although hunger is an indicator of being more attuned to true physiology, this research suggests that food-related behaviours can become associated with a wide variety of cues and stimuli in ways that are divorced from our physiological needs.
This may explain why dieters with high restraint are always worrying about their eating habits or caloric intake and lose control over their diet under varying situations.
Findings in this paper, published in the journal Psychological Science, call for further investigation in humans on the implications of rigid and flexible dieting attitudes for weight maintenance.