Nerves in the stomach act as a circadian clock that tell us how much to eat and when, a new study finds.
Have you ever wondered why your stomach automatically starts growling as meal time approaches? Or why you can't consume even a morsel more, despite wanting to? A new study conducted by University of Adelaide researchers may have an answer.
The study is the first of its kind to state that nerves in the stomach act as a circadian clock, telling us when to eat and in what quantity, according to a press release.
"These nerves are responsible for letting the brain know how much food we have eaten and when to stop eating," said Dr Kentish, who is the lead author of the paper. "What we've found is that the nerves in the gut are at their least sensitive at time periods associated with being awake. This means more food can be consumed before we feel full at times of high activity, when more energy is required.
Researchers also found that the amount of food you can consume largely depends on the time of the day. They stated that as the time for you to sleep nears, the nerves in your stomach become more sensitive to even the slightest stretch and signal fullness to the brain quicker than during the day. This limits food intake as the night approaches. This mechanism is repeated every 24 hours, like a circadian clock.
Though these findings were made in laboratory studies and not tested on humans, researchers speculate that it is the same in humans too because they have the same nerve responses in their stomach.
"We know that shift workers, for example, are more prone to disruptions in sleep and eating behaviour, leading to obesity and other health problems. We are now conducting further research to see what kind of impact such changes to the circadian rhythm will have on eating behaviour, and how the nerves in the stomach react to those changes," Associate Professor Page said.
Findings of the study will help researchers better understand how and when the gut sends signals to the brain that we're full and how changes in this circadian clock can affect an individual's eating habits.
This is not the first time researchers have compared the mechanism of the human anatomy to that of a clock. In a study conducted in October, researchers uncovered the presence of an internal biological "clock" that proved helpful in aiding scientists measure the age of most human tissues. With the help of this clock, researchers were able to determine that breast tissues age faster than any other tissue in the body.
Findings of the new study were published in The Journal of Neuroscience, December 5, 2013.
