The search for the Fountain of Youth took Ponce de Leon to the sunny climes of Florida in 1513, and many a retired snowbird has followed ever since.
But in Japan, home of the fastest-ageing society in the world, the search took me to the kitchen of Tokyo restaurant owner Yoshinari Suzuno in the ritzy Ginza shopping district. It is there that Suzuno serves up bowl after bowl of steaming nabe, or hotpot, a hearty soup of chicken, cabbage, shiitake mushrooms, onions and mizuna, a peppery mustard green.
Nabe has long been a staple of Japanese cuisine, but Suzuno's version has a special ingredient that is rumoured to keep patrons looking forever young: collagen.
The connective protein in bones, skin and cartilage, collagen provides structure and firmness to body tissue.
But we lose collagen as we age, and that allows wrinkles to form.
If we can get it back, the thinking goes, we can keep our smooth skin and baby faces that much longer.
Simply put, the Japanese are trying to eat their way back to youth.
Piled on top of the meat and vegetables in congealed mustard-yellow clumps, chicken collagen is melted down to form the broth of Suzuno's nabe, in contrast to the traditional mixture of water and chicken stock.
Although the concoction is wholly unappetising in appearance when it emerges from the kitchen, collagen is popular in Japan, especially among women eager to lap up the latest trend in the ever-burgeoning skin-care market.
Suzuno said he goes through nine eight-litre containers of collagen every day, and his is one of dozens of restaurants across the city that serve collagen nabe.
In Japan, which boasts the highest percentage of residents over 60 and the longest life spans in the world, the bid to defy the wear and tear that Father Time brings has become an industry.
Cocktails at trendy bars are infused with collagen, and small bottles of daily liquid-collagen supplements - with pink caps and wrappers aimed at attracting women - dot shelves at convenience stores, selling for about $2.50 each.
Satoshi Hirota, a spokesman for the Shiseido beauty company, which markets a popular collagen supplement, said sales were up 65% last year compared with 2007, the first year they were on the market.
That is remarkable, considering that nutritionists have been sceptical about the health benefits of eating collagen, which they say is digested by amino acids in the same way as any other protein and thus offers no special effects.
"There is no evidence that dietary collagen intake facilitates collagen biosynthesis," said Kuniko Takahashi, a nutrition scientist at Japan's Gunma University, who took a bite out of collagen's mythical power in her book Truth and Falsehood of Food Information.
"Many people cannot think critically about eating or nutrition information, so they are misled by commercial advertising," she said.
"Many companies promote collagen benefit through their marketing."
Yet in a country where women routinely carry parasols and wear long-sleeve shirts and elbow-length gloves in the summer, many are taking no chances.
Fumiyo Adachi, a health-care technician, was sitting at the bar at Suzuno's restaurant polishing off a bowl of nabe.
Ms Adachi is 35 but looks half a decade younger.
Her skin is pale, clear and blemish-free, and she credits the soup. "This is my third time here," she said.
"The first time I came because I heard it was good for skin. It was so good, I came again. I definitely think my skin looks different the next day, but it only lasts two or three days."
Nabe is most popular in the winter, but restaurants such as Yoshinari, which is named for its owner, serve it year-round.
Suzuno said he came up with the idea for a collagen broth before it became trendy because he was looking for a better-tasting soup.
Never mind that collagen is tasteless. He explained that he bought the collagen from a manufacturer and stored it in the eight-litre vats in his refrigerator for two days to let it congeal.
No preservatives are added.
The moment the dish arrives at the table can be jarring for first-timers, as it was for the colleagues who took me to Yoshinari for a welcome party shortly after I arrived in Tokyo.
They had never eaten collagen nabe, and they ogled as Suzuno brought the dish to our table and lit the gas fire under the clay pot.
Each of us sampled a small piece of congealed collagen; it tasted like salty jelly. Before long, the collagen had melted into a rich broth over the meat and vegetables, taking on a strong, salty chicken flavour.
Some of my co-workers insisted that the broth was heartier than traditional nabe broth.
After we had each had a bowl of chicken and vegetables, a waitress returned with a bowl of noodles, which were added to the broth for a second course.
So: real thing or placebo effect? I didn't think I looked any different the next day, though my colleagues and I joked about our youthful appearance.
Suzuno is a believer, though. He is 41, and he insisted that his skin is that of a younger man, thrusting his cheek towards me for inspection. Truth be told, I noticed a few crow's-feet. But I didn't have the heart to tell him.
- David Nakamura of the Los Angeles Times-Washington Post