A new study may help explain why we always have room for ice-cream; and no, it's not because the “dessert stomach” is a completely different stomach altogether.
Even after our bodies have consumed adequate (or possibly more than enough) calories to sustain our energy needs, we often still engage in post dinner snacking - especially picking at delicious foods that are directly in front of you.
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Researchers at the University of Naples (SUN) in Italy have dubbed this phenomenon "pleasure eating" or "hedonic hunger", referring to the "desire to eat for pleasure, and to enjoy the taste, rather than to restore the body's energy needs".
"Desiring and eating a piece of cake even after a satiating meal is consumption driven by pleasure and not by energy deprivation," said study researcher Dr Palmiero Monteleone.
Dr Monteleone explains that when we eat for pleasure, the body releases chemicals that could stimulate overeating.
"The physiological process underlying hedonic eating is not fully understood," he says, "but it is likely that endogenous substances regulating reward mechanisms like the hormone ghrelin and chemical compounds such as 2-arachidonoylglycerol (2-AG) are involved."
To test this theory, the researchers took eight adults aged between 21 and 33 and fed them their favourite foods. The participants were then given less desirable foods of equal value in terms of calories and nutrition.
The researchers measured the levels of the two 'reward' chemicals being released in the blood stream at both times.
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The results showed that higher levels of the chemicals were being released while the participants were eating their favourite foods.
This suggests that the reward system sends stronger signals that could override other signals the body releases to indicate satiation or the fulfilment of its energy needs.
"Hedonic hunger may powerfully stimulate overeating in an environment where highly palatable foods are omnipresent, and contribute to the surge in obesity," said Dr Monteleone.
"Understanding the physiological mechanisms underlying this eating behaviour may shed some light on the obesity epidemic.
"Further research should confirm and extend our results to patients with obesity or with other eating disorders in order to better understand the phenomenon of hedonic eating."
The study will be published in the Journal of Clinical Endocrinology & Metabolism.
Your say: are you guilty of "pleasure eating"?
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