What Causes a Food Coma?

Though the phrase “food coma” has become just another way of saying “I ate entirely too much,” it’s a real phenomenon. There’s even a term for it: “postprandial somnolence.” So why do we frequently feel like we need a three-hour nap after demolishing a burger and fries for lunch? It’s not just from overeating — protein and salt could help contribute to that feeling of post-meal fatigue, a new study indicates.

Researchers from Bowling Green State University in Ohio and Florida’s Scripps Research Institute recently set out to study the cause of food comas, investigating the neurobiological connections between fruit flies’ eating and sleeping patterns.

As ScienceDaily explains, “The cause of the food coma turned out to be protein and salt, along with the time of day the food was consumed. Surprisingly, sugar did not seem to play a role, according to the study.”

One of the researchers, Dr. Robert Huber, suggests that it could be because of the relative rarity — and value — of protein, an “expensive commodity.” In short, more energy needs to be put into extracting the goods out of protein or salt, resulting in that post-burger naptime. Moral of the story: Maybe avoid a a gigantic burger if you’ve got an important meeting after lunch.

The team behind the study are still looking into the exact explanation for why sleep is helpful after eating protein or salt (as far as fruit flies are concerned, anyway). Now if only a scientist would tackle the meat sweats.

• Neuroscientist Probes Fruit Fly to discover Sleep/Eating Connection [ScienceDaily]
• Protein, Salt Drive Post-Meal Sleepiness [ScienceDaily]
• More Science Coverage [E]