LECTURE/Longevity expert talks about what it really takes to reach the age of 100.

Secrets to living longer—a lot longer

Living to 100 may seem like quite an achievement, but according to longevity expert Thomas Perls, centenarians are the fastest growing segment of the population. Reaching 105, though, is “really very special” says Perls, an associate professor of medicine at Boston University Medical Center and director of the New England Centenarian Study.

Perls, who spoke here Jan. 12 as part of the Institute on Aging’s Visiting Scholar Series, has been studying centenarians since 1995 and now directs the largest such study in the world. The vast majority of centenarians, he says, are 100 years old. Getting to 105 is in another league altogether, and reaching 110—becoming a “supercentenarian”—is very rare indeed. The oldest person in Perls’ study was Sarah Knauss, a resident of Allentown, PA, who lived to 119.

There’s a commonly held assumption, said Perls, that centenarians must all be demented, sick and “at death’s door.” The idea that, “the older you get the sicker you get” is simply not true, he said. In fact, it’s almost the reverse. “The older you get, the healthier you’ve been.” At 102, he said, 50 percent of men and 33 percent of women are still able to function independently. “That doesn’t sound so great,” said Perls, “but if you go back to the age of 92 we see 100 percent of men and 88 percent of women” functioning independently. In other words, old people not only live longer, they also have a much shorter period when they are sick and dependent on others.

Living to an advanced age in good health sounds pretty good. So how do you do it? Genes clearly play a role, and women tend to have a natural advantage, but according to Perls lifestyle choices are also a huge factor. Studies have shown that Seventh Day Adventists—who are all vegetarians, neither drink nor smoke, exercise frequently and set aside time for spiritual activities—have the highest life expectancy of any group. “If we all became like Seventh Day Adventists,” said Perls, “the health payoff to the public would be enormous.”
Perls has noticed his centenarians—”these people I love and adore”—possess certain personality traits in common. They score low in neuroticism, are able to manage stress and tend not to dwell on things or internalize problems. They are rarely depressed and are notably outgoing and humorous.

“Does it help to be married?” asked one audience member. Most female centenarians are not married, said Perls, while almost all men who reach 100 are married. Though many of the women were widowed by spouses who died in their 70s or 80s, that’s not the whole story. Perls found that 18 percent of the women in his study had never been married. “Maybe it’s because they’re unusually assertive and independent. Most said they didn’t want to get married, they just weren’t interested.”

Perls continues to explore why women live longer. Now that estrogen is no longer thought to be the reason, Perls is looking into “interesting literature” that iron plays an important role in cells’ ability to produce free radicals, the unstable atoms that can damage cells and lead to age-related diseases. Having less iron may produce fewer free radicals. Perhaps, then, because women menstruate for 40 to 50 years they have less iron and fewer free radicals.

Perls is sufficiently convinced by the theory to give a pint of his own blood every eight weeks at a nearby hospital to make himself “more female.”