Every year, on the Fourth of July, Americans eat hot dogs. A lot of hot dogs. According to the National Hot Dog and Sausage Council (yes, such a thing exists), 150 million of them, to be exact -- enough to stretch from Washington D.C. to Los Angeles over five times. Independence Day just wouldn't be the same without them.
But there is a small group of people who eat a whole lot more hot dogs than the rest of us on July 4. They are the contestants of Nathan's Famous Fourth of July International Hot Dog Eating Contest, an annual competition held in the Coney Island neighborhood of Brooklyn, New York that attracts 40,000 fans and is broadcast on ESPN to nearly two million viewers nationwide.
Competitive eater Joey Chestnut currently holds the official world record for eating 68 hot dogs and buns in 10 minutes. He'll seek his sixth straight win this year, during the men's championship round at noon on Wednesday. Sonya Thomas, who ate 40 hot dogs and buns in 10 minutes last year in the first-ever women's championship, will defend her title at 11:30 a.m.
This year, the gorge-fest will air at 3 p.m. on ESPN (to accommodate Wimbledon coverage), and while it certainly provides entertainment, it also raises some questions, namely, what are the effects on the body of eating so much in so little time.
First, a look at the basics: According to nutrition facts listed on the Nathan's website, each hot dog packs 290 calories, 17 grams of fat and 710 milligrams of sodium. That means chowing through 68 hot dogs provides almost enough calories as someone on a 2,000-calorie-a-day diet would need in ten days.
Very little research exists surrounding the effects of competitive eating on the body, mainly because so few people are compelled to stuff their faces for a living. But one study remains the most commonly-cited reference whenever the topic comes up, as it seems to each year when the hot dog eating contest rolls around.
A team of radiologists and gastroenterologists published the study in 2007 in the American Journal of Roentgenology. They had 29-year-old competitive eater, Tim Janus (as part of a National Geographic special), and a 35-year-old male control eater eat as many hot dogs as they could in 12 minutes, and then performed a series of stomach scans to see how both men handled all those dogs. (Click over to the study to see photos of the scans.)
The regular eater finished seven hot dogs before he tapped out; the competitive eater ate 36 before the researchers said he could stop, they had seen enough. His abdomen, which had appeared flat before the eating began, now "protruded enough to create the distinct impression of a developing intrauterine pregnancy," the researchers wrote, while the average eater's stomach appeared just as it had before.
"Normally, the upper stomach expands to accept the food," Dr. David C. Metz, one of the co-authors of the study, and a professor of medicine in the division of gastroenterology at the Perelman School of Medicine at the University of Pennsylvania tells The Huffington Post. "The muscles relax to receive the food and that increases the volume of food you can put into it without increasing pressure." As pressure increases in the average person's stomach, they burp, experience nausea or even vomit. "Our hypothesis became that [competitive eaters] have the ability to relax their stomachs to such a degree that they can just eat and eat until you and I would be ready to pop."
Metz compares the average human stomach size to that of two fists, able to contain maybe a liter or so in volume at rest, he says. There hasn't been any research to quantify how much more a competitive eater's stomach can expand, but Metz offers the following analogy: While eating, the average person's stomach may expand to hold two or three liters, he imagines, whereas a competitive eater's may expand to hold six or seven.
There hasn't been any research into how competitive eaters come to react this way. Metz believes it's a combination of nature and nurture. Many are probably born with an innate ability to relax the stomach so they never seem to reach a point of feeling full, but they also probably train themselves to expand their stomachs even larger, he says.
Janus indeed told Metz and his colleagues that he didn't feel full during the experiment -- or ever. Instead, he avoided gaining weight by measuring portions of food and resisting the temptation to indulge in seconds. While this self-discipline has kept him trim and fit until now, the researchers wrote, "It is easy to envision a scenario in which aging speed eaters lose their willpower and engage in chronic binge eating because they never feel sated."
But, in fact, the majority of the successful eaters on the professional circuit aren't morbidly obese.
The thinking goes that thinner people have the advantage because their stomachs can expand with less fat pushing against the organ, ABC News reported. To stay in competitive shape, though, requires training -- and not just sitting around and eating.
"The new generation of eaters is interested in weight lifting, running," Jason Fagone, who followed competitive eaters to write "Horseman of the Esophagus" told CNN. "They have more athletic body types than the old generation." He said competitive eaters liken an annual hot dog eating competition to running a marathon -- yes, both are stresses to the body as it is pushed to the extreme, but they are occasional ones.
Chestnut himself detailed some of what goes into this training to WebMD, saying about once a week he eats a whole bunch of whatever food is up next on his competitive circuit to "slowly make my body adapt to my goal." He'll also drink a gallon of milk in one sitting to train his stomach to expand.
"Psychologically, I like to go in hungry," he told the website. "If I see on the scale that I have dropped weight, I can easily imagine an enormous amount of food inside me." That's why he says he sticks to protein supplements in the days before an event. He also goes back to supplements for a day or two after an event or a training session as his stomach empties out.
And what about for those watching at home? Eating competitions can "send a message to spectators that going hog wild with food is not a big deal," American Dietetic Association spokesman and nutritionist Milton Stokes told WebMD.
"It's like magic -- a magical American myth," Adrienne Rose Johnson, a doctorate student at Stanford, told GOOD. Johnson wrote a paper called "Magic Metabolisms: Competitive Eating and the Formation of an American Bodily Idea." "I think it speaks to people suffering from literal and symbolic consequences of consumerism.”
Metz agrees. Humans are hard-wired to seek out food and eat as much of it as possible, stemming from an age when food was less available and we didn't always know when we could expect our next meal. But now that food is so accessible and those genetic tendencies still remain, our waistlines are continuously growing.
Not to mention, there are tremendous risks associated with stuffing the stomach to its capacity, even just one time -- like rupturing the stomach, he says. "Make sure the public knows not to try this at home."
With a sample size of only one, the researchers acknowledge that their results, for now, are only speculative. But they conclude that the glory of winning the Mustard Belt may not outweigh the serious health risks:
A chronically dilated, flaccid stomach may eventually decompensate, so that it becomes an enormous sac incapable of shrinking to its original size and incapable of peristalsing or emptying solid food. If this happens, long-term competitive speed eaters ultimately could develop intractable nausea and vomiting, necessitating a partial or total gastrectomy to relieve their symptoms and restore their ability to eat. Thus, speed eating is a potentially self-destructive form of behavior that over time could lead to morbid obesity, intractable nausea and vomiting, and even the need for gastric surgery.
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