Who lives the longest?

What is the secret of a long life? Everyone wants to know — especially Thomas Perls, a School of Medicine associate professor of geriatrics. Perls, who believes longevity is a combination of heredity and lifestyle, is heading the Long Life Family Study at the BU Medical Center (BUMC). BU is one of five universities collaborating on the $18 million National Institutes of Health study.

BUMC, Columbia University, the University of Pittsburgh, the University of Southern Denmark, and Washington University will each sign up 250 families with many members in their 80s, 90s, and 100s to glean information on what contributes to a long life. Many researchers have found that living to an old age is determined about 30 percent by genes, but Perls is also looking for other factors. Mailings went out in May to a random sample of people on the U.S. government’s Medicare list, and those who choose to participate are answering questions about their health and lifestyle during a two-hour session.

For the study, which is expected to take about five years for surveying and analysis, researchers will also request a blood sample to obtain information about participants’ genes. Perls is also the director of the New England Centenarian Study at BUMC, the largest comprehensive genetic study of people over 100 years old in the world. In this landmark study, which began in 1994 and has involved 1,500 subjects to date, Perls found that brothers of centenarians are 17 times more likely — and sisters 8 times more likely — to reach 100 than their counterparts in the general population.

These people aren’t drinking from the fountain of youth, Perls says, but they are enjoying the benefits of what he likes to call “the fountain of aging well.” In 1999, Perls and Margery Silver, a MED assistant professor of geriatrics, wrote a book titled Living to 100: Lessons in Living to Your Maximum Potential at Any Age, detailing their conclusion that several factors can contribute to extending maximum lifespan, including limiting dietary intake. “The only thing we really know that can really slow down aging, and perhaps delay the diseases associated with aging, is caloric restriction,” says Perls. Indeed, many uncontrollable factors affect the length of life, but the fact remains that obesity is rare among centenarians. Those who live to 100 also tend to be nonsmokers and score low in a domain of personality testing called neuroticism — meaning they tend to be “stress shedders” and immune to “unhealthy feelings, like anger, fear, guilt, and sadness,” he says. “If people can emulate centenarians, either through stress reduction programs, alternative approaches like yoga, or a regular physical exercise program, we believe they stand a much better chance of coping with the mental and physical problems of old age.”

It’s no secret that survival advantage is prevalent in some families because of genetics, Perls says, especially after his research team at the New England Centenarian Study, in analyzing the genomes of 308 centenarians and their siblings, discovered a “genetic booster rocket” for longevity. They pinpointed a region on human chromosome 4 that is likely to contain a gene or genes associated with extraordinary life expectancy. “With scientists at a company called Centagenetix in Cambridge, we’ve been working to find the gene that plays a role in lifespan,” he says. Exploring the gene’s biochemical pathways could lead to the development of age-slowing and disease-retarding drugs, and Perls believes that the Long Life Family Study could play an important role in this quest.

The Long Life Family Study is not only the largest-ever federally funded study of longevity in families, but is also the first to attempt to pinpoint the environmental, lifestyle, and genetic issues involved, rather than focusing on just one factor.

The average life expectancy in the United States is 79.9 years for women and 74.5 years for men. It is projected that for people born in 1910, only 7 of every 10,000 women and 3 of every 10,000 men will live to see their 100th birthday. But most of us have what it takes to get to our mid- to late-80s in good health — with or without a genetic booster rocket — if we regularly exercise, maintain a lean body mass, and don’t smoke, according to Perls. “Doing those things will enable most of us to preserve our health and vitality,” he says.