(Eat this, Japan!)

American eating phenom Joey Chestnut — who finished a close second to world champion Takeru Kobayashi at last July’s hot dog-eating contest at Coney Island — has chomped right through Kobayashi’s all-time record, downing 59-1/2 hot dogs and buns last week in a regional qualifying heat in Arizona.

The stunning consumption of Chestnut — whose personal best before Saturday was 52 HDBs last July 4 — makes Kobayashi something he’s never been before: the underdog at the annual Independence Day contest at Nathan’s in Coney Island.

Some are calling Chestnut’s 59-1/2 HDB performance the greatest achievement in the history of human competition.

“It’s the greatest achievement in the history of human competition,” said George Shea, chairman of the International Federation of Competitive Eating, the governing body of all stomach-centered sports.

“I saw the 1969 Super Bowl. I saw Michael Jordan’s three-peat (although, admittedly, I was getting a sandwich during one of the peats). I saw Secretariat win the Belmont by 31 lengths. What Chestnut has done makes all those sporting achievements look like a one-run win in a pickup softball game.”

Detractors immediately suggested that Chestnut could never have chewed up such high numbers had he been competing in the heat and humidity of a normal summer day, rather than in an air-conditioned mall in suburban Tempe. Indeed, even Shea admitted that hot weather at Coney typically reduces consumption by “two to five dogs.”

“Remember that very hot July 4, 2003? Kobayashi, who had never eaten less than 50 suddenly could only down 44-1/2,” Shea said. “He still won, but he would’ve committed seppuku had we not reminded him that the steamy temps were to blame.”

Still, Shea said Chestnut’s 59-1/2 HDBs was such a “monumental” performance that the man they call “Jaws” would still have broken the record even if he’d been in a sauna.

“The true challenge will come — as it always does, like the Grim Reaper himself — on July 4 at Coney Island,” Shea added. “If he can put up numbers like that at the actual contest, he’ll go down in the history books, and I’m not talking about Wikipedia, but a real history book.”

Kobayashi did not respond to e-mails from this reporter, who (full disclosure) served as his judge and counter during his unprecedented six-in-a-row championships from 2001-2006 at the July 4 contest.

That an American now holds the world record for hot-dog-eating brings the sport of competitive gluttony back to what some call its glory days. Before the so-called “Japanese Invasion” of 1996, American eaters such as Ed “The Maspeth Monster” Krachie, Mike “The Scholar” DeVito and Frank “Hollywood” Dellarosa lorded over the champion’s table.

But none of those fabled frank-ophiles ever ate more than 22-1/4 HDBs. And ever since the diminutive Japanese phenom Hirofumi Nakajima beat the enormous Krachie in a one-on-one stuff-your-faceoff in December, 1996, the coveted Mustard Yellow International Belt has remained around thin Japanese waists for every year except 1999.

The most widely accepted explanation for the Japanese prowess is Krachie’s own “Belt of Fat” theory. The 300-pound Krachie argued in a well-researched (but ultimately rejected by the Journal of the American Medical Association) paper that his own abundant adipose tissue around his midsection prevented his stomach from expanding to hold more hot dogs, while the thin Japanese eaters had highly developed abdominus rectus muscles that allowed the stomach to stretch and contain more and more chewed-up hot dogs and buns.

Chestnut is the greatest of a new wave of lightweight American eaters — the so-called “Thin-icans” — who are leading the charge to keep the belt on American soil.

But first, Chestnut will have to win it back on July 4.

As they say in the competitive eating world, that’s a tough nut to eat 59-1/2 of.

Jaw-dropping feat

When Joey Chestnut downed 59-1/2 hot dogs and buns in 12 minutes last week, he not only set a new world record, but also took care of his eating for at least a week. Here’s how Chestnut’s stunning performance shapes up (or doesn’t shape up):

Total calories: 18,385 (9.2 days’ worth)

Total sodium: 40,698 mg (17.2 days’ worth)

Total fat: 1,195.95 g (18.4 days’ worth)

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