A recent study provided clues as to why people, even when overweight, crave and consume rich foods despite the negative consequences. The answer is that in this circumstance the brain needs increasingly greater amounts of rich foods just to be satisfied. It’s a vicious cycle — eating rich foods begets cravings for even more rich food. In this experiment, the more an animals’ diet consisted of these rich foods, the more they ate, in fact twice as much as animals given other diets. Okay, so at this point, nothing surprising — perhaps the rich foods tasted better and therefore the animals ate more.
This is where the interesting part of this study comes in — the consumption of rich foods itself produced a biological need to eat even more rich food just to be satisfied. The biological need was demonstrated by measuring activity in the reward centers of the brain. As rats continued to eat this rich-food diet, for any given amount of food consumed there was less activation of the reward center. Increasing amounts of food became required just to reach a minimum satisfaction level.
In fact, this drive became so strong it was undeterred even by shocking the feet of these rats — they just kept eating the rich foods. Similar findings have been seen in cocaine addiction. In the case of food addiction, normalization of reward center responsiveness took even longer to occur when diets were changed back to healthier ones compared to how long it took in the animal models of cocaine addiction when cocaine ingestion was stopped. The specific biological basis of the change in reward center responsiveness involved the chemical messenger Dopamine, and the Dopamine docking stations, or receptors, in that area of the brain. The animals stopped producing as many of these receptors, so more and more activity was required to achieve the same effect.
So if anyone thinks it’s easy to lose weight… A successful weight management program may include medication support in addition to dietary and activity level modifications.
Regards, Dr. Ranen (Psychiatrist Baltimore, Baltimore County, Owings Mills) DrNealRanenBaltimorePsychiatrist.com