Last Living Man Born in 19th Century Likely Has Genes to Thank

Jiroemon Kimura, the world's oldest living man, celebrated his 116th birthday last Friday. Photo credit: Kyotango City Government/Getty Images

Jiroemon Kimura, the oldest living man, celebrated his 116th birthday this past Friday. Born in 1897, Kimura is the last man alive born in the 19 th century, according to the Guinness Book of World Records. The resident of Kyotango, Japan, is also the oldest man in verified history.

Should Kimura be interested, there are plenty lovely ladies in his age group to choose from. The Gerontology Research Group at UCLA lists 21 women born before New Year's Day in 1901 who are still alive and well. And the current world's oldest living woman, 115-year-old Misao Okawa, also lives in Japan.

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These golden agers are part of an elite group of seniors who have made it to their 110 th birthday and beyond. Dr. Tom Perls, the director of the New England Centenarian Study at Boston University Medical Center, estimates there are approximately 200-300 of these "supercentenarians" in the world.

So what's the secret to living long enough to blow out at least 110 candles on your birthday cake?

"People who live to that age are incredibly homogeneous, as if they have some key genetic features in common that get them to an incredibly old age," Perls said.

One commonality Perls' studies have found: Approximately 90 percent of superagers are women. He speculates that having two X chromosomes offers a certain amount of protection from disease and disability.

"If one chromosome has some less-than-desirable aging or disease genetic variance, women seem to have the ability to choose a variant on the other chromosome that is more conducive to survival," he explained.

One of Perls' studies also showed that women who conceived naturally and carried a baby to full term after age 40 are at least four times more likely than average to live to the age of 100.

As for living a clean lifestyle, Perls said the research is mixed, with one study showing approximately 20 percent of those over the age of 103 practicing truly horrendous lifelong health habits including smoking, drinking, eating junk food and avoiding exercise.

Perls recalled that the oldest woman on record, Frenchwoman Madame Jeanne Calment, who died in 1997 at the age of 122, smoked heavily until she was 100 years old and continued to smoke one cigarette a day thereafter. Perls wondered if she would have lived even longer had she kicked the habit.

However, Perls stressed that it is very rare to find a smoker who makes it past the century mark. The same holds truly of anyone who is even mildly overweight.

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Perls concedes supercentenarians, with their superior anti-aging genes, probably aren't the best lifestyle role models. Better to look to the Seventh Day Adventists, he said, a religious group whose active, vegetarian, highly social lifestyle appears to promote longevity.

"They live to an average age of 88, versus an average 78 for the rest of us," he pointed out.