Captain America had a memorable sendoff in Avengers: Endgame, but one fan theory adds a darker element to his Marvel Cinematic Universe story. In Endgame, Captain America (Chris Evans) goes on one last journey with his Avengers team. The film showed the character was worthy of carrying Mjolnir, and he led the Avengers in their eventual win over Thanos (Josh Brolin). Then, while returning the Infinity Stones to their appropriate timelines, Captain America decides to stay in the past, only returning as an older man to pass on his shield and Captain America duties to Anthony Mackie's Falcon.

Chris Evans' character went on a long journey in the MCU. Marvel introduced the character to audiences in 2011's Captain America: The First Avenger, and Steve Rogers emerged as a leader of Marvel's superhero team in 2012's The Avengers. Ever since, Captain America became a staple of the MCU, often bringing characters together in his self-titled films, such as Captain America: Civil War. Throughout his journey, he constantly puts the wants and needs of others above his own, even if it risks his life. Captain America's self-sacrificing nature makes his ending, which reunites him with Peggy Carter (Hayley Atwell), an earned and worthy goodbye.

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Though Captain America constantly puts his life on the line for others, one theory suggests that the superhero takes ample time for himself. A viral theory (via Reddit) claims, "Captain America poops a lot." The theory essentially comes down to a line in The First Avenger. In the film, Cap tells Carter that he can't get drunk, and Hayley Atwell's Peggy Carter responds, "Your metabolism burns four times faster than the average person." It's one of the side-effects of the super serum. Because of that, the theory states Captain America needs to eat four times more than others, and he either has "massive poops that are four times the size of normal poops" or goes to the bathroom "four times" more than an average person.

Steve Rogers on a plane in Captain America

The theory stinks for Captain America. Chris Evans' character was onscreen for more than an hour in Endgame. If he relieves himself more often than other people, that could've been a challenging hour indeed. After all, Cap is usually on the move in the MCU. So when Captain America travels to the past to return the Infinity Stones, he likely wouldn't have an appropriate amount of time to sneak away for a bathroom break. And with the fate of the Multiverse on the line, holding it is likely his best option.

Of course, a faster metabolism doesn't necessarily go hand-in-hand with relieving oneself. In fact, several factors go into digestion besides metabolism (via The Cleveland Clinic), including body type, medications, types of food eaten, and stress level. As commenters on Reddit noted, Captain America's body works more efficiently than regular bodies, so he could absorb more from the food and therefore not have massive doo-doo duties in Avengers: Endgame. So, in the end, Captain America could poop just like everyone else, though that may not stop him from being the butt of potty humor.

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