A recent study published in the Journal of Neuroscience by authors Peggy Mason, PhD, professor of neurobiology, and Hayley Foo, PhD, research associate professor of neurobiology at the University of Chicago, is the first to show that while ingesting food or drink, a powerful painkilling effect occurs.
They found a region in the brainstem called the raphe mangus (known to blunt pain during sleep and urination) that regulates this pain response. The brainstem is what controls our breathing and perspiration subconsciously.
In their experiment on rats, they found the animals didn’t lift their paws off a hot light bulb under their cages when they were eating a chocolate chip or drinking sugar water. They were even more surprised to find that even when they replaced the sugar water with regular water; the rats also delayed lifting their paws off the hot cage floor.
When they gave the animals bitter quinine; they found the rats made a “gape that’s akin to a child’s expression of ‘yuck.’” And they reacted to the heat under their cages quickly. So, the researchers concluded that only pleasurable food triggers pain relief.
Surprisingly enough, when the rats were ill; the chocolate chip didn't delay the pain response, only plain water delayed the pain under all conditions.
Mason believes this effect is in humans as well, previous studies showed sugar water reduced pain in infants getting booster shots.
This brainstem controlled pain relief effect might have been a natural blessing for animals in the wild. The brainstem trigger made sure they would eat as much as possible (when the food is non-toxic and pleasurable) and not be distracted by pain while they were eating.
The researchers though consider this natural pain killing effect, a problem for modernized humans because of the large quantities of pleasurable foods available to us around the clock. The brainstem (which functions subconsciously) will trigger you to eat the entire bag of (pleasurable) potato chips until its empty, even though the conscious mind knows it’s full and should stop.
Should obesity be blamed on our brainstems triggers?
No. Since the research shows plain water triggers the same effect as hedonistic foods.
Peggy Mason concludes: "Ingestion is a painkiller but we don't need the sugar, so replace the doctor's lollipop with a drink of water."
