Jan 04, 2013 06:56PM ● Published by Anonymous
But have you ever wondered why?
According to researchers from the University of Naples, Italy, it’s because our brain rewards us.
Their study, which was recently published in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism, found that when we eat out of desire rather than hunger, our brain’s endogenous reward chemicals (those that come from within the brain), such as the chemical compound 2-arachidonoylyglecerol (or 2-AG for the non-scientists among us) and the hormone ghrelin, are activated. Naturally, we keep eating. For the study, University of Naples researchers enlisted the help of eight healthy adults between the ages of 21 and 31. During what study authors dubbed the hedonic process, they fed them their favorite foods. Later, they treated them to a not-so-appetizing menu of equal nutrient and caloric value. Throughout the study, the researchers kept a close watch on the participants’ 2-AG and ghrelin levels.
What they found may help explain exactly why we eat when we don’t need to.
During the hedonic process, the participants’ ghrelin and 2-AG plasma levels increased. During non-hedonic eating, they didn’t. That means that their brain’s chemical reward systems were activated when they ate their favorite foods, and overrode those saying that they’d eaten enough.
The same can be applied to that slice of post-work chocolate cake. And the little sliver after that. We’re not eating them to refuel our body’s energy, but our brain tells us to keep going. For a lot of us, the hedonic process winds up with our laying on the couch, clutching our full bellies, and swearing to never eat cake again. And it’s probably a few weeks before we eat until the point of pain again. For others, though, hedonic hunger can lead to serious health complications.
“Hedonic hunger may powerfully stimulate overeating in an environment where highly palatable foods are present, and contribute to the surge in obesity,” said lead study author Palmiero Monteleone in a statement. “Understanding the physiological mechanisms underlying this eating behavior may shed some light on the obesity epidemic.”
But this study was just a pilot, and focused only on healthy individuals with normal body masses. Monteleone believes that further research could confirm and extend its results. By looking at patients with obesity or other eating disorders, scientists could come to better understand hedonic hunger, and how exactly it plays into our relationships with food, patterns of eating, and weight.