WIKIMEDIA, LOTUS HEADA chronic high-fat diet is thought to desensitize the brain to the feeling of satisfaction that one normally gets from a meal, causing a person to overeat in order to achieve the same high again. New research published today (August 15) in Science, however, suggests that this desensitization actually begins in the gut itself, where production of a satiety factor, which normally tells the brain to stop eating, becomes dialed down by the repeated intake of high-fat food.
“It’s really fantastic work,” said Paul Kenny, a professor of molecular therapeutics at The Scripps Research Institute in Jupiter, Florida, who was not involved in the study. “It could be a so-called missing link between gut and brain signaling, which has been something of a mystery.”
While pork belly, ice cream, and other high-fat foods produce an endorphin response in the brain when they hit the taste buds, according to Kenny, the gut also sends signals directly to the brain to control our feeding behavior. Indeed, mice nourished via gastric feeding tubes, which bypass the mouth, exhibit a surge in dopamine—a neurotransmitter promoting reinforcement in the brain’s reward circuitry—similar to that experienced by those eating normally.
This dopamine surge occurs in response to feeding in ...