Scientifically, there are a number of reasons why this happens, from activity inside the body to the production of insulin. In fiction, however, a food coma is typically a result of pigging out on food, particularly fatty foods like meat. There is a biochemical case for this portrayal too; meat contains tons of protein, and when this is broken down, one of the amino acids obtained is tryptophan. This amino acid, among other functions, is crucial for the production of the hormones serotonin - the feel-good hormone - and melatonin. Both hormones are utilised to help you relax and sleep, so it makes sense that eating foods rich in tryptophan would help you drop off.
This is a common Sitcom trope; it invariably comes into play in a festive or holiday episode, when the family have just had the major annual blowout (Thanksgiving in American sitcoms, Christmas in British) and the camera pans around a room full of comatose and happy people. Farting or Faceplanting into Food may be added for extra laughs.
Needless to say, this is Truth in Television. See Acid Reflux Nightmare, Balloon Belly, and Death by Gluttony for other negative effects of eating too much. Compare with Brain Freeze for another type of negative consequence after eating.
- Bobobo-bo Bo-bobo: In Chapter 39, Bobobo makes Suzu eat an entire coelacanth, which the latter does quickly and with no hesitation. She smugly tells Bobobo that she managed to eat it all when he turns his attention back to her, but Suzu is so heavily bloated that she winds up passing out seconds later.
- Ace in One Piece has a habit of falling asleep while eating, often to the shock of onlookers.
- This is... actually more or less the entire premise of Marvel's limited series Night of the Living Deadpool. After one of his usual bloody missions, the merc with the mouth chows down on enough tacos to put him into a food coma. Upon waking up, he discovers the world is overrun by zombies, with the Avengers along with all of Earth's other heroes long dead. Wade Wilson must team up with a ragtag group of survivors to combat the plague. Or... it's just a really bad dream caused by his taco coma.
- Cloudy with a Chance of Meatballs: Cal, the son of the police officer, goes into a coma from eating too much junk food and Manny the retired doctor diagnoses him with a "food coma". He manages to wake Cal by breaking a celery in front of his face, but then Cal throws up.
- In The Lorax, some bar-ba-loots and the Lorax himself are seen looking groggy after eating nine servings of pancakes.
- Tremors 3: Back to Perfection: While their previous stage, the Shriekers, multiply if they eat, the Ass-blasters go into a food coma when they eat too much. Nancy and Mindy are able to capture one because of this. This leads to a scene where Burt destroys his entire house and everything in it to kill an Ass-blaster before it can get to his supply of MREs (Meals-Ready-To-Eat), fearing that like the Shriekers the creature will vastly multiply when it eats enough food, only to learn afterwards that letting the creature stuff itself would have actually incapacitated it.
- In Ralph S. Mouse, Ralph eats beans from a mosaic painting, but this makes him sleepy and he falls asleep.
- Downplayed in Bugs Bunny: Too Many Carrots, which is a book based on Looney Tunes. After their Eating Contest, Bugs and Hogitall both look a little groggy but only for one page.
- In the Xanth series of books, this trope is referenced by Smash Ogre, during a story where his intelligence was greatly enhanced by an Eye Queue vine. At one point, he found himself in an unfamiliar area, where there were many things that ogres love to eat. Due to his new intellect, this made him suspicious, and he reflected that if he was still a dumb ogre his instinct would have been to eat all he could, at which point he'd like get drowsy and fall asleep. He decided to not eat anything and stay hungry and alert until he could figure out what was going on.
- Poor Stuffy Pete in the O. Henry short story "Two Thanksgiving Day Gentlemen" qualifies after he guilt-trips himself into eating two huge Thanksgiving dinners in immediate succession provided by mutually unaware benefactors.
"Around the first corner Stuffy turned, and stood for one minute. Then he seemed to puff out his rags as an owl puffs out his feathers, and fell to the sidewalk like a sunstricken horse."
- In Howard Mohr's How to Talk Minnesotan, he instructs the following, concerning being invited over for Sunday dinner:
If you are invited to Sunday dinner in Minnesota, don't make plans for later in the day. After you eat you are obliged to move into the living room for conversation conducted through yawns. If there's no football game on TV or you can't hold your eyes open any longer or you are listing in the lounger more than forty-five degrees, you should go someplace where you can lose consciousness without drawing attention to yourself with unusual body noises."After a meal like that, a guy gets logy.""Why don't you take that back bedroom? There's a comforter in the closet behind the card table."By 3:45, everybody will be strung around the house sawing logs. Don't just lie down and read magazines or snoop in the drawers. Take off your shoes and go to sleep. You should have crease marks on your face from the bedspread when you come back out around 5:30 or 6.
- In an episode of Barney & Friends, B.J. notes that while he usually doesn't take naps anymore, he may take one today as his "square meal" he had after the square dance (the episode was all about squares and they added the meal and the dance as sort of a joke) has made him sleepy.
- In an episode of Star Trek: Voyager, there are some aliens who don't use furniture when they eat because they can lie down and take a nap after eating.
- The Dark Crystal: Age of Resistance: The Chamberlain returns to the castle from a LONG and arduous trek after losing Rian only to find his fellow Skeksis have fallen into one of these after decimating the uprising of the Castle guard and devouring the combined life essence of all the gefling thereof.
- The Mythbusters tested this in the episode "Food Fables". The myth that the tryptophan in turkey, traditionally served on Thanksgiving, is what makes people sleepy was busted. Tory and Grant were given some tryptophan as a control, its effects were identical to the amount of turkey they ate as well as the mashed potatoes mixed with protein powder (but no tryptophan), which was resulted in this trope. However, when given that same amount of turkey and smaller portions of the other sides, they had plenty of energy to move around.
- Very common after a meal at Howard's house on The Big Bang Theory, as his mom is a Supreme Chef who specializes in briskets, roasts, casseroles, and other comfort foods, and happily feeds her son and all his friends until they're stuffed. Soon after she dies, a power outage forces Howard and Bernadette to either throw out all the food she had saved in the freezer... or invite their friends over, warm the food up in the gas stove, and enjoy her cooking one last time. In a moment that is both funny and heartwarming, the last scene shows all the main characters collapsed around the living room, completely ready to fall asleep from all the carbs they ate.
- Discussed on Roseanne, Darlene confesses to almost leaving home after a fight with Roseanne about college. Roseanne indignantly says she's been watching her like a hawk all week, to which Darlene dryly replies, "Hawks don't usually pass out on the couch after eating a quart of ice cream."
- Chappelle's Show: A Season 2 episode features a sketch where Dave, restless because of a big meeting the next day, is offered a sleep aid called Ribs.
- "Once ingested, Ribs go to work on your stomach, spreading barbecue sauce and greasy porkiness throughout, creating an age-old condition called 'The Itis.' You'll feel sluggish, drowsy, and should be asleep in a matter of minutes."
- Friends: In "The One With All The Thanksgivings", everyone is collapsed into chairs after the meal, groaning from how much they've eaten. They're so lethargic that no-one is willing to reach for the controls to turn the TV on, not even Phoebe, who is right next to them. Although they're all so stuffed they feel they can't eat another bite, Joey is still craving something sweet.
Phoebe: Monica, your remote doesn't work.
Monica: Phoebe, you have to lift it and point.
Phoebe: Oh. Aw, forget it.
- House of Anubis: In one episode, Eddie talks Jerome into a bet that involves Jerome eating several gallons of creamed carrot, all in one sitting. After a montage of Jerome forcing himself to choke down the food and nearly throwing up at the end, we next see him lying down in his bed, feeling sick and exhausted.
- Taz-Mania (SNES, 1993): At the end of each level when the sufficient amount of Kiwi are eaten, Taz will get stuffed and drift off to sleep with his mouth open, at which point all the "collected" Kiwi (as well as any eaten bird, Bushrat, and whatever food powerup Digeri handed to him for some reason) escape from his mouth unharmed.
- Yandere Simulator: All the rivals from the 1980's mode state that they sometimes fall asleep after eating too much.
- My Little Pony: Equestria Girls Digital Series: In the Pinkie Pie ending of "Wake-Up!", Sunset and Pinkie both end up in one after gorging on sweets, with Sunset having a massive stomachache and suffering nausea.
Rainbow Dash: Nobody should try to keep up with Pinkie Pie.Applejack: Not even Pinkie Pie.
- PONY.MOV: Applejack ends up in a coma as a result of eating too many apples that lasts until the very last episode of the series where she not only recovers from her coma, but returns from another dimension she ended up in from it.
- Red vs. Blue: In Season 15, the Blood Gulch Crew travel to Earth to fight the Blues and Reds. Grif eats a ton of the meth-methshrooms he found when the BGC were living on the planet they were native to in order to take out a lot of the grunts, only to wind up crashing and falling asleep a few minutes later when Carolina radios him to help out the others.
- In a Chainsawsuit post-Thanksgiving comic, a character suffers a "gastriac arrest", so the doctors have to stabilize him by putting him in a "medically-induced food coma".
- Grace of El Goonish Shive went into a "pancake coma" for a few hours shortly after eating a huge meal (shown here) at a pancake house.
- There are several online lists, including this one, of lists of excuses parents can give if they forget to move the Elf on the Shelf. One common one is "The elf ate too much and got too sleepy to move".
- Neopets: The Turmaculus is a Turmac that ate too much food. Not only has he become massive as a result, but he spends most of his time asleep- the game with him involves attempting to wake him up.
- Sailor Moon Abridged has The Movie mention that Serena fell into one for seven years and when she woke up, she had a daughter. Best not to think how that came to be.
- The Boondocks episode "The Itis" not only popularized its titular slang term, it also served as a ruthless mockery of this trope, as well as soul food in general. The itis becomes a recurring sight at the Freeman family dinner thanks to Robert's obscenely unhealthy food, with everyone but Huey falling asleep from eating it. Noticing a business opportunity, Ed Wuncler Sr. helps Robert open a soul food restaurant called "The Itis" revolving around the concept. Hilarity Ensues as the food proves not only fattening, but also incredibly addictive, and soon the area around it is riddled with obesity and crime. In the end, the restaurant is shut down due to legal issues, and the Freeman family switches to healthier food.
- Family Guy: In "The Fat Guy Strangler", Peter and his friends go to a steakhouse and become lethargic after eating, with Peter managing to eat seven 16oz steaks!. They then make fun of Joe for not being able to finish one.
Joe: Oh, I can't do it. I'm... I'm so full.
Peter: Full of what? Estrogen?
- Jellystone!: The episode "Gorilla in our Midst" has Grape Ape falling asleep in the middle of the city from eating too much spaghetti and meatballs, causing huge destruction in the process. Yogi, Boo Boo, and Cindy work to try and wake him up by removing a giant meatball in his stomach and concocting "wake up juice" before Jellystone starts devolving into more panic and chaos.
- Kid vs. Kat: Invoked in "How The Test Was Won", where Kat prepares turkey and warm milk for Coop to eat so he will be so sleepy that he will be unable to study or make it to school in time for a test he has to take to get his grades up. Sure enough, Coop gets completely knocked out by it and wakes up the next morning in Old Lady Munson's birdbath.
- The Loud House:
- In "Snow Way Out", the Loud kids eat three burgers each to try to find a winning ticket, and after their third burger, they all look groggy. They perk up pretty quickly, though.
- In "The Loudest Thanksgiving", Lincoln remembers that in previous Thanksgivings, he always ate too much and fell asleep, so this time he's trying not to.
- Invoked in the Mega Man: Fully Charged: episode "Trust Your Guts, Man" when Mega Man defeated Guts Man (who gains power from eating) by overfeeding him, causing him to collapse.
- Phineas and Ferb:
- In "Candace's Big Day," Doofenshmirtz keeps eating vegetables dipped in greasy food additives thinking it'll make him healthy, and he gets so bloated and unhealthy that he passes out in the grease vat.
- Exploited in "Gi-Ants" when Doofenshmirtz makes a Turkey-inator to turn things into giant roasted turkeys, so once everyone eats the turkey, the effect of tryptophan will tire them out and Doofenshmirtz can take over the Tri-State Area.
- Total Drama:
- Before revealing the true challenge in "The Big Sleep", Chris makes the campers run twenty kilometers and surprises them with a delicious turkey buffet. It is only then that everyone gets the nasty surprise that they'll be holding a contest who can stay awake the longest. The exercise and the turkey meat are to ensure the contest won't take too long.
- Dinner in "The Treasure Island of Doctor McLean" consists of a pasta dish with mutant turkey meat. The mutant meat knocks everyone out cold, which is the intended effect so that the campers can be set adrift on rafts for the challenge the next morning.
- In the VeggieTales episode Lord of the Beans, Ahem tells Toto that he lost the wishing bean while in a sugar coma caused by eating a 200-pound marshmallow Peep.