Is there a physical limit to how much food you can eat in one sitting?

If you had to pick the world’s greatest ever athlete, who would you put on your shortlist? Usain Bolt, Serena Williams, Muhammad Ali, Tiger Woods, Roger Federer, or Michael Phelps?

No doubt they have all dominated their sports at various times, but what about Joey Chestnut?

Most people have probably never heard of him; but for the 2 million viewers who tune in to what must be the weirdest event of the US sporting calendar, Joey “Jaws” Chestnut is a bona fide legend.

Chestnut is the undisputed champion of competitive eating and has utterly dominated the hundred-year-old ‘Nathan’s Famous Fourth of July International Hot Dog Eating Contest’ – an event that has become the must-see event for Major League Eating fans everywhere (yes, seriously).

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Every summer, frankfurter-guzzling heavyweights fly in from all corners of the globe to stuff themselves silly for ten minutes in front of a crowd of 40,000 screaming spectators, each hoping to return home with the victor’s Mustard Belt.

Chestnut, a 100kg food hoover has been toppled only once since 2007. He has broken more world records than any other competitor, and at this year’s event he broke his own world record (again) by ingesting a gut-busting 76 hotdogs (buns included) in ten minutes – one more than he did at the 2020 socially-distanced event.

You might scoff at the idea that this grotesque gladiatorial spectacle could be considered the world’s fastest-growing ‘sport’, but this rapidly ballooning industry has just birthed some serious and thought-provoking science research.

An investigation published in the respected academic journal Biological Letters, has deduced that the 10-minute record will never exceed 84 hotdogs – this is the absolute human limit. According to the paper’s author, Dr James Smoliga, not even Chestnut could eat any more.

This is undoubtedly click-bait science of the highest order, hitting the tabloid headlines, and it carries the distinct whiff of fast food industry-funding. Rest easy though, any worries that Big Hotdog are taking a bite out of independent science research are unfounded.

Chatting with the slim-framed Dr Smoliga one lunchtime, he explained to me that the annual hotdog eating contest has been a “guilty pleasure” for him since the 1990s. He told me that this investigation was a natural evolution from his previous track-and-field performance research: “It just dawned on me: I bet the hotdog competition follows the same pattern [of performance seen in other sports]”.

Taking the baton on from other scholars who have used statistics and high-level mathematics to predict the limits of human physical abilities – such as the theory that the marathon will never be run in under 1hr 58.05 seconds – Smoliga plugged in 39 years’ worth of Hotdog Eating Contest data to these sophisticated mathematical models.

Plotting the results on a graph, it was “very clear”, he says, that competitive eating abilities have improved on a trajectory that almost exactly mirrors that of other sports.

Throughout the 1980s, hot dog eating records improved only slightly year-on-year – equivalent to other, more conventional, sports before they turned professional. Victors of the burgeoning event were a mostly “bunch of objectively obese men”, Smoliga explained, capable of forcing down about one hot dog per minute.

This all changed in 2001 when highly trained Japanese eaters suddenly burst onto the scene, rapidly devouring the competition. Leading the pack was super-eater Takeru Kobayashi, who made light work of the competition, doubling the then world record from 25 to 50 hotdogs on his first appearance.

Ding-dong battles between Kobayashi and America’s best eaters saw a flood of sponsorship money and the curious competition quickly turned professional. With greater incentives comes greater participation, improved training techniques and strategy.

The early 2000s in competitive eating parallel the huge gains made in athletics in the 1970s and 1980s. The new generation of competitive eaters train themselves hard. Realising that excess fat stifles the stomach’s ability to rapidly inflate, competitors exercise to keep themselves trim, and train their bodies to tolerate ever-increasing amounts of food without gagging.

By regularly slurping vast amounts of soup, a competitive eater can progressively stretch their stomach, much like how ear lobes can be stretched to extraordinary proportions with gauge earrings.

Smoliga’s analysis deduced that the absolute maximal ‘active consumption rate’ (ACR) – the amount of fresh matter than can be consumed in given time – would be 832 grams per minute. Not content to leave it there, he went on to compare human food gobbling abilities with other animals.

“I thought that this is going to be a really interesting topic to write about and to explore the underlying science,” said Dr Smoliga. In the league table of motor mouths, Homo sapiens are on par with Grizzly bears, faster than coyotes but not even Joey Jaws himself could bolt food faster than a wolf (which can consume over a kilogram of meat per minute).

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Top competitive eaters’ abilities are astonishing – Chestnut wolfed down nearly 7.5 kilos of food (22,000 calories – enough for ten days’ worth of food) in his 2020 triumph. This is roughly equivalent to him inflating the stomach to the size of a nine-month pregnant uterus!

The science may show that competitive eating serves as a curious thought experiment for understanding human abilities, it doesn’t offer us an easy answer on whether you consider this potentially dangerous discipline is a true sport.

“I’m not sure I want to be on the record either way,” Smoliga tells me, “but if I had to choose, I would call it a sport – if Bass fishing is a sport, then this is a sport – although I wouldn’t recommend it!”.