How many hot dogs can a human eat in 10 minutes?

All I ever wanted as a scientist was to work on interesting problems. I’ve also long contended that almost any subject is interesting if you approach it from the right angle. I’d argue that James Smoliga feels the same way. Smoliga, a physiologist and physiotherapist, recently conducted a study of historical data from Nathan’s Famous Coney Island Hot Dog Eating Contest to scientifically assess the long term performance increase of these “elite athletes.”

Essentially all competitive sports exhibit a long term improvement that will plateau at some point. Take sprinters, for instance. It is possible to use physiology to determine the maximum theoretical speed that a human could possibly run. Usain Bolt is famously the fastest runner ever officially clocked, with a peak speed during the 100 meter sprint of 27.51 mph. Scientists estimate that humans have a peak sprint speed of between 35 and 40 mph, which is about half the top speed of the fastest quadrupeds. It is reasonable to expect that over time, with improved nutrition and biological sciences, humans will get faster and faster, but will plateau somewhere around 40 mph.

It seems that competitive hot dog eating has undergone a similar trend in just 40 years, and that humans might be reaching the plateau very quickly. The limit to how many hot dogs a human can eat in 10 minutes is dominated by how far a human stomach and stretch to take on an ungodly amount of sausage. (With running, the limiting factor is how fast human leg muscles can move, which is based on the rate that muscles can contract and expand, so in a way it’s a very similar problem.) A more scientific term for stomach stretchiness is “gut plasticity,” and Smoliga has calculated that maximum human gut plasticity is equivalent to eating 84 hot dogs in 10 minutes. The thing is, the present world record is 75 hot dogs in 10 minutes. If you plot the “active consumption rate” of hot dogs – defined as hot dogs per minute – in the Nathan’s contest since 1980 you get the following chart.

The circles are data from 10 minutes competitions, and the squares are from 12 minutes competitions. In 1980 it was pretty much one hot dog per minute, or 10 hot dogs in 10 minutes. And that is what is so incredible. Every physical sport has this shape of curve, but the time between the low point and the plateau is usually much longer. As fast as Usain Bolt is, he is nowhere near the theoretical maximum human speed. Joey Chestnut, who holds the present record at 75 hot dogs in 10 minutes, is very close to the theoretical maximum of 84. This leads to an interesting question: Why are competitive eaters progressing up the curve so much faster than other athletes?

Smoliga proposes an answer. In competitive running, an athlete must train their body to undergo an intense physical strain. This training turns them into a very specialized, and highly adapted, peak physical specimen. A competitive eater must also train their body, but rather than improving physical fitness, what might actually be happening is a chronic form of damage. It’s a lot easier to break something than it is to fix it, and that may be exactly what competitive eaters are doing to their own guts. Smoliga argues that high performance competitive eaters haven’t been around long enough to assess the long term health implications of this sport, but in general increased gut plasticity to the point that normal gut plasticity is no longer possible would not be good for long term health. It’s not a shock that routine binge eating (“training”) is probably not good for you.

So there you have it. Nathan’s Famous Coney Island Hot Dog Eating Contest is a great case study for a weird bit of human physiology. And you probably thought it was just a silly sport.