A plot where a character is inspired to go vegetarian, but finds themself back to their original omnivorous diet again by the end of the episode.
There are several common reasons that lead to a character deciding to do so. The characters might have learned how meat is produced and became so disgusted that they decided to abstain from meat for good. It might have been done for health reasons (since vegetarians are typically healthier than non-vegetarians), in which case this might overlap with a Diet Episode.
- In an Archie Comics story, Big Eater Jughead decides to become a vegetarian, or at least a "health food nut". Consequently, malt-shop owner Pop Tate converts his store into a health bar (since Jughead formerly bought enough hamburgers there to keep him in business). When Pops asks Jug how carrot juice and such makes him feel, Jughead pleads for a hamburger or six, and everything's back to the status quo.
- In The Murder of Roger Ackroyd, Caroline prepares only vegetarian meals whenever Poirot visits, in order to impress him. Of course, he figures out that Caroline is not actually vegetarian.
- The first time the team tries out their wolf morph, Cassie smells bacon on Rachel, who'd apparently mentioned going vegetarian earlier.
- Inverted in a later episode where the team infiltrate a meat-packing plant. Most of the story (written from Ax's perspective) was a pro-vegetarian screed by a ghostwriter, so the ending features everyone ordering big, juicy, greasy hamburgers.
- One episode of Friends had the vegetarian Phoebe craving meat during her pregnancy. Joey helped her deal with it by offering to go vegetarian himself but begins having meat cravings as well.
- In the Black Books episode "Hello Sun", Fran falls under the influence of her Granola Girl friend and tries to go on a vegan diet. After her new healthy lifestyle wreaks havoc on her friendship with Bernard and Manny, she goes back to her old habits.
- This occurs in the 3rd Rock from the Sun episode "I Brake for Dick" when hitting a chipmunk with his car inspires Dick to engage in various Animal Wrongs Group antics, including forcing the whole family to follow a vegan lifestyle. In the end, the chipmunk, after being nursed back to health, is released into the wild, only to immediately become prey for a peregrine falcon. Realizing that Nature Is Not Nice, Dick gives up the vegan lifestyle.
- That '70s Show: After Red suffers a heart attack, his wife Kitty, a registered nurse, makes him go without meat, cheese, or beer. Naturally, Red hates this, so when he's on his own, he tries to sneak in a cheeseburger and fries till Hyde finds out. Later, during dinner, he has to have rice while everybody else gets fried chicken, which leads him to say "This isn't food, this is what food eats!".
- In The Nostalgia Critic's review of Suicide Squad (2016), this trope is brought up when Diablo, who supposedly sworn off violence for years, drops this oath after a few moments of touching him against his will.
Deadshot: Is that really all it took to get you back into violence?Diablo: Yeah, I know...Captain Boomerang: Years of pacifism destroyed by tapping on your head?Diablo: I just don't like people touching my head, okay?! It's annoying!Deadshot: (snicker) Well, we "appreciate" your "sacrifice".Captain Boomerang: Yeah, it's like one of those guys going vegan for a day.Deadshot: I know, right? Pussy.
- Jacksfilms went vegan for an hour and live-streamed it.
- Played with in Braceface. In the fifth episode, "The Meat of the Matter," Sharon decides to become a vegetarian after seeing the unsavory conditions of her new job at a meatpacking plant. Sharon ultimately stays a vegetarian for the rest of the series, but almost gave it up in the second-to-last episode, "Vegging Out," after she develops an iron-deficiency anemia and some of her friends suggest that Sharon should start eating meat again to boost her iron levels. However, vegetarianism is too important to Sharon for her to give it up, so she decides to stay a vegetarian while looking for ways to put more iron in her diet.
- In the aptly named Teen Titans Go! episode "Vegetables", Beast Boy finally manages to convince the others to try vegetables. It went horribly right and caused them to summon the Monster of the Week.
- In the Arthur episode, "Sue Ellen Vegges Out", Sue Ellen becomes a vegetarian (and has remained that way ever since). When she announces her decision to her friends, Sue Ellen explains that she's thought about going vegetarian for a while—in the episode's intro, it's shown that what ultimately pushed Sue Ellen into finally going full vegetarian was befriending a female pig named Sally. In the same episode, Muffy and Francine get into a competition about who can last longer as a vegetarian: Muffy tries going vegetarian because a celebrity she likes becomes a vegetarian, then she goes back to eating meat when the celebrity adopts a bologna-diet. Francine then decides to become a vegetarian just to show up Muffy, but Muffy does her best to sabotage Francine. Sue Ellen soon gets fed up with her friends' behavior and explains that the main reason she decided to become a vegetarian was that she considers animals her friends, so she lost her taste for eating them. In the end, Francine and Muffy decide that vegetarianism just isn't for them and apologize to Sue Ellen for how they acted, and they both promise to be supportive of her decision to be a vegetarian; they even help make more vegetarian options and “Meatless Mondays” in their school's cafeteria.
- In one episode of Kenny the Shark Kat decides to go vegetarian after watching a documentary on lions. She tries to get her pet shark to be too. It backfires as expected.
- Stan from South Park ends up becoming vegetarian in "Fun with Veal". He quits after contracting Vaginitis from not eating meat. The joke references Cartman earlier saying "If you don't eat meat you become a pussy" and the disease has the individual literally breaking out with vagina-like sores all over their body.
- The Simpsons:
- Averted in the "Lisa the Vegetarian'" episode. Despite her young age and her parents trying to stop her, Lisa stays vegetarian and has consistently been depicted as such since. The reason why Lisa remains a vegetarian after that episode is because Paul McCartney agreed to make a Special Guest appearance in that episode on the condition that Lisa would not have a Snap Back after this episode.
- In "A Star Is Torn", when the Simpsons weren't able to go dinner shopping at the Kwik-E-Mart, Lisa sees the Spucklers' produce stand next door, she suggests that the family has an organic vegetarian meal for dinner. The family enjoys the meal at first, with Homer declaring that he doesn't miss meat at all. However, since the family (minus Lisa) is so used to eating processed foods, everyone (except for Lisa) comes down with a really bad case of food poisoning. The morning after, the family's feeling better and are through with vegetables. Notably, Lisa doesn't mind their decision, being relieved that they're at least recovering.
Bart: From now on, I'm only eating food that I know had a soul.
- In the Avatar: The Last Airbender episode "Bitter Work," Sokka gets stuck in a hole chasing a baby saber-tooth moose-lion cub. He pleads with the universe, promising to never eat meat or be sarcastic ever again if it will just let him out. Of course, once his friends rescue him, he immediately decides to do no such thing.
- King of the Hill: In "And They Call It Bobby Love, Bobby temporarily became vegetarian in order to impress a girl, who was not interested in him in that way. He later runs into her at a steakhouse after they broke up and participated in a steak-eating contest (and won) just to spite her.
- Christian fasting:
- Catholics, Anglicans, and Methodists are expected to abstain from meat on Fridays during Lent as a commemoration of Jesus' crucifixion on that day. Prior to the 1960s, it was every Friday year-round.
- Very traditionalist Orthodox and Coptic Christians have so many rules regarding fasting (which, in the Christian tradition, is more about abstaining from luxuries rather than not eating at all), that many of them would be essentially eating vegan (or very close to it) for a whole third of the year. Orthodox Christians, for example, have four major fastsnote ; every Wednesday and Friday for almost the entire year note , and several more one-day fastsnote .
- "Meatless Monday" is a variation in which a usually omnivorous person goes without meat every Monday (though it doesn't have to be specifically on a Monday) to cut down on their meat consumption.
- According to this study 84% of vegans and vegetarians eventually return to eating animal products (at least on a semi-regular basis) making this trope Truth in Television more often than not.
- Some people just don't feel like eating meat during the summer, making them vegetarians for a couple of months.
- Some women go vegetarian or vegan while pregnant for the health of their baby, then return to eating meat once they've given birth.
- And conversely - many vegan women crave meat during pregnancy and give in to their cravings. Generally pregnant women tend to crave things that are not part of their everyday diet.