- [Host] What's it like to eat 58 hot dogs in ten minutes?

- I mean, it is kind of fun.

I think one time I gained like 25 pounds in ten minutes.

I dunno if it's fun, but it's kind of insane to think about it.

- [Host] So what happens inside the bodies of competitive eaters as they tackle pounds of food in just minutes?

- The stomach has a fascinating organ.

It's really two organs in one.

The top part of the stomach is a receptacle and the bottom part of the stomach is a grinder.

- [Host] When food lands in the upper part of the stomach, the stomach naturally relaxes and expands.

The pressure on the other organ sends a signal to the brain, "I'm full and need to burp."

This is your body signal that you should stop eating.

Competitive eaters can dramatically relax and stretch their stomachs.

That stretching allows them to eat more without feeling full and they also train themselves to push past the feeling of fullness.

- The speed eater just has a bigger capacity at complete relaxation and a less of a stimulus to, "I'm feeling full and I need to stop."

- [Host] This is where the speed eater's unique ability comes into play.

- The way we look at the stomach, it's just like a big muscle and I think a resting stomach of an above average eater can maybe hold three quarters of a gallon or six to eight pounds, but we can hold sizeably more than that.

- [Host] The ability to expand the stomach is likely a combination of innate ability and dedicated training.

- But it's similar to somebody who might have a genetic tendency towards sprinting or towards marathoning.

They have muscle fiber types that might lend themselves to either races that are intense and short and super fast, or long and steady.

However, you can't get to the elite class of either kind of races without training.

- So the normal preparation for competitions is practice with the food, which sounds good, but it's not great.

And then you just drink a large amount of liquid to try to expand your stomach.

- You have to always be trying to get a little bit more food in than you could in the past.

That's the only way to really grow.

- [Host] Even with training and innate physiological advantages, the most seasoned speed eater will get tired during a competition.

- You do a contest, it may only be eight minutes, it may only be ten or 12.

It doesn't sound like a lot of time, but when you're spending that entire time just shoveling food down at a really quick rate, it feels like a marathon.

- It is really taxing on the body and a lot of the times, you're just really pushing your body to the limit and you end up like sweating a lot, which is a little odd because you're eating, but it is pretty physical.

- [Host] So what happens in the body when you put that much strain on it?

Typically as food moves into the lower part of the stomach, it mixes with gastric juices and then gradually empties into the small intestine; a process that usually takes about four hours.

But experts say that consuming larger quantities of food at a time may complicate digestion.

- Undigested matter can stay in the gastrointestinal tract for days, disrupting the gut microbiome.

For example, there's risk of small intestinal bacterial overgrowth, abdominal pain and diarrhea, and associated symptoms.

- [Host] Consuming massive amounts of food in a short period can also cause it to sit in the esophagus as it waits to enter the top part of the stomach.

The food piled up can cause vomiting or suffocation.

It may also cause longer term harm to the esophagus and the stomach.

- If you get a tremendous expansion and rupture, you can actually rupture and tear the esophagus, which is called a Boerhaave Syndrome, in which case all those contents leak into the chest and become septic, and it can be really dangerous.

In theory, I think you could potentially rupture the stomach if you just stretch it out far enough.

- [Host] Research on how much the stomach and esophagus can stretch, and whether the stomach can fully return to its original size, is limited.

Scientists are uncertain but they're concerned about permanent loss of stomach elasticity.

- The stomach will relax and expand, and now the question is, can the stomach un-relax and sort of get back to its normal size?

Can those muscles get damaged so much that they don't work properly?

- [Host] If those muscles are permanently damaged, it could cause a disorder called gastroparesis.

This essentially means the stomach muscles are paralyzed, leading to issues like poor digestion, bloating and acid reflux.

To counteract the short-term effects of speed eating, some competitive eaters may try to eat healthy foods, exercise regularly or fast before and after competitions.

Still, participating in training and events does often take a toll on metabolism, muscle health and the body's ability to recognize the feeling of fullness.

- The day after a contest, because you have just had that giant stretch, it is really hard to feel full after that with a normal meal.

And so that part is a lot of like, training your brain to stop eating at a normal time even though you have no sensation of fullness for like, the next week or so.

'Cause you've stretched that out and it's gotta kind of bounce back to normal.

- Through the years, my hunger and my metabolism has definitely slowed down, but I think it's all been pretty relative.

- [Host] Whether or not it takes a lasting toll, competitive eating is certainly extreme.

- I don't think it's terribly unhealthy, but I don't think it's something that I personally would recommend.

I play golf.

(gentle music) - You're still here?

You must really like what you just saw.

If you really did like it that much, take a look at the channel memberships we have.

You can get custom emojis and badges, access to content before it releases, members-only invites to live events and more.

And the money you give actually comes back here to Nova so we can keep making this amazing content for you.

Click the join button now to check it out.

Thanks for watching Nova, and see you again next time.