The gross-out science of hot dog eating contests

Goes down smooth.
Goes down smooth.
Image: AP Photo/Tina Fineberg
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Monday (July 4), Americans will celebrate their independence from Britain with a quintessentially American competition: the 100th annual Nathan’s Hot Dog Eating contest on Coney Island in New York.

Last year’s reigning champion, Matthew Stonie, 24, wolfed down 62 hot dogs with buns in 10 minutes; the current record of 69, held by 32-year-old Joey Chestnut, was set in 2013. If a contestant breaks that record this year, their nutritional consumption would look something like this:

On any given day, most adults should consume between 1,200 to 2,000 calories; winners of hot dog eating contests eat 10 days worth of energy.

More concerning is how much sodium they consume. We need sodium to function; it plays a role in chemical signaling, blood pressure, and muscle contraction. But we really don’t need more than 1,500 to 2,300 milligrams per day (most Americans eat 3,400 milligrams). Americans get 75% of their sodium from processed and restaurant foods; a teaspoon of table salt contains 2,300 milligrams.

Too much sodium is hard on our kidneys, which filter our blood. To balance extra sodium in our blood, our bodies hold onto extra water. Extra water makes our cells larger (has it ever been hard to take your rings off after eating a really salty meal?), but it also increases the amount of blood in our veins. More blood means more work for our hearts and blood vessels. Over time, the added stress can cause vessels to thicken, which can cause high blood pressure, heart attack, stroke, and general heart failure.

Salt makes us thirsty as our body tries to take in more water, but this can be a double-edged sword: More water exacerbates swelling, and not enough means our bodies try to take salt from other cells, leading to dehydration.

In most cases, your body will balance out its sodium levels on its own. You may feel swollen, bloated, and thirsty, after a few hot dogs this weekend, but after drinking water and taking a break from eating, your body’s levels will even out.

Balancing salt and water becomes trickier in competitive eating. Competitive eaters often will use water to flush food down their gullets. ”In some cases, there’s a concern that if [competitive eaters] drink a lot of water in order to push the food down, and they might get water toxicity,” said Nieca Goldberg, a cardiologist at NYU Langone Medical Center. Water toxicity, or hyponatremia, develops we don’t have enough salt in our cells and they swell up with extra water.

The sheer volume of food can also overwhelm the gastrointestinal tract, causing it to malfunction. On the one hand, Goldberg explained, eating that much that quickly may force food through our systems faster than we have time to absorb all the nutrients and calories from it. But sometimes, inexplicably, the reverse happens.

“These people kind of stun the system. We call it call it gastroporesis, where the motility really slows down,” she said. If you keep eating without pushing food down, eventually your stomach may stretch to the point where you’re forced to retch, which damages your esophagus and teeth by forcibly exposing them to undigested food and stomach acid.

Sometimes, the esophagus can tear from throwing up, which can be deadly. “The partially digested contents can go and be aspirated into the lungs, resulting in an inflammatory condition like a pneumonia,” Goldberg said.

Undigested food in the lungs? No thank you.

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