Why Do You Get Sleepy After Eating? These Are the Top Theories

If eating makes you tired, you’ve got something in common with most people—and, for that matter, with most living things. Researchers have turned up evidence of “postprandial sleepiness,” also known as a food coma, in insects, snakes, worms and rats. “The conservation of this behavior across species suggests that it’s really important for something,” says William Ja, an associate professor of neuroscience at the Scripps Research Institute in Florida who has studied this food coma phenomenon. Some experts have hypothesized that animals—humans included—have built-in “vigilance signals” that keep them awake and alert when hungry. These signals help them locate and acquire food. It follows that once an animal (or a human) has eaten a lot, these vigilance signals dissipate and are replaced by feelings of fatigue. Others have theorized that post-meal changes in blood circulation could explain why eating makes some people sleepy. Blood flow to the small intestine “dramatically increases” after a person eats, says Dr. Tomonori Kishino, a professor of health science at Japan’s Kyorin University. And as blood is pumped into the gut to fuel digestion, a corresponding drop in blood flow to the brain could trigger feelings of sleepiness, he says. Some past research into this hypothesis concluded that blood flow to the brain does not change after a person eats a meal. But some of Kishino’s recent w...
Source: TIME: Health - Category: Consumer Health News Authors: Tags: Uncategorized Diet/Nutrition Source Type: news