When was the last time you ate so much you passed out in a “food coma?” Is such a thing really possible?
Yes, indeed. Overeating before passing out even has a scientific name: postprandial somnolence. (Try saying that three times fast.)
It isn’t really a “coma” in the technical sense since those stricken with postprandial somnolence can be roused – cautiously, like a hibernating bear. But why does gorging lead to sleeping?
When we eat, the stomach produces gastrin, a hormone that stimulates digestive juices. When food leaves the stomach and enters the small intestine, other hormones – enterogastrones – are released which influence bodily functions (e.g., regulating blood flow).
Less blood flow to the brain after eating may make you a bit woozy. It also turns out that foods full of fats or carbohydrates make you sleepy. However, a balanced meal rich in protein does not have this effect.
In addition, during digestion, the body’s parasympathetic nervous system lets us relax, while the sympathetic nervous system that acts fast in stressful situations dials itself back. When the parasympathetic system focuses its energy on the gut, you may feel chilly after “eating large.”
A glass of warm cow’s milk drunk before bed is thought to lead directly to Slumberland. This is due to the melatonin (a natural hormone that regulates our night or day rhythm) in the milk. Melatonin is secreted by the pineal gland inside the head, which is most active around three or four in the morning.
Eating a lot of sugary and high-carb food causes insulin production to reduce blood glucose back to its normal level. The insulin spike stimulates the production of brain hormones – like melatonin and serotonin (the “feel good” hormone). However, we don’t recommend eating junk food to treat insomnia.
Restless researchers continue to figure out just why pigging out can lead to nodding off. A Big Think article describes “a special system called Activity Recording CAFE (ARC) for visual tracking of the food consumption and motion of the flies.”
Although the fruit flies tested typically sleep in much smaller, more frequent periods throughout the day and night than human subjects, they are great for testing purposes, according to William Ja associate professor at Florida’s Scripps Research Institute: “Sleep is really hard to study in people since very few can sleep ‘normally’ when they’re being watched.” I totally get that.
High-protein, high-salt, large meals caused the flies to sleep up to twice as much in a 40-minute period as they typically would if they hadn’t eaten anything. Interestingly, meals high in sugar had no similar effect.
The food coma effect was stronger in the morning for the fruit flies, suggesting that the body’s circadian rhythm (internal clock) regulates the time of day (or night) that eating is likelier to slow you down.
What have we learned?
- A food coma is a real physiological reaction to overeating.
- Foods high in protein and salt, eaten in large quantities, make you the sleepiest.
- Feeding time influences the degree of food coma experienced.
If food comas are a problem for you, try eating less, obviously. Balance proteins, fats, and carbs. Take meals regularly – don’t fast and binge – and include some physical activity afterward to balance your blood sugar.
Be like celebrated American humorist Erma Bombeck, who quipped:
“I am not a glutton – I am an explorer of food.”