August 3, 2011
Lifestyle Of Centenarians Not Always Healthier
According to researchers at Albert Einstein College of Medicine at Yeshiva University in New York, regular exercise, drinking in moderation and watching what you eat makes no difference to your chances of reaching the century mark.
Researchers studied nearly 500 people between the ages of 95 and 109 and compared them with more than 3,000 others born during the same period. They found that those who lived long lives ate, drank and smoked just as much as those who hadn't lived as long, and also had just as little exercise and were as likely to be overweight as their long-gone counterparts.
The findings, published Wednesday in the online edition of the Journal of the American Geriatrics Society, suggests that protective longevity genes may be more important than lifestyle behaviors when it comes to living a long life.
Nir Barzilai, M.D., the Ingeborg and Ira Leon Rennert Chair of Aging Research and director of the Institute for Aging Research at Einstein, and his colleagues interviewed 477 Ashkenazi Jews who were living independently and were 95 years old or older -- 75 percent of which were female. The participants were enrolled in the college's Longevity Genes Project, an ongoing study that seeks to understand why centenarians live as long as they do.
Descended from a small founder group, Ashkenazi Jews are more genetically uniform than other populations, making it easier to spot gene differences that are present.
The elderly participants were asked about their lifestyles at age 70, considered representative of the lifestyle they had followed for most of their adult lives. They answered questions on their weight and height so the researchers could calculate their body mass index (BMI). The participants also provided information about their alcohol use, smoking habits, physical activity, and their diets.
To compare these individuals with the general population, the team used data from more than 3,100 people who had been born around the same time as the centenarians and were examined between 1971 and 1975 while participating in the National Health and Nutrition Examination Survey.
The researchers found that overall, people with exceptional longevity did not have healthier lifestyle choices than the comparison group in terms of BMI, smoking, physical activity, or diet. They found that 27 percent of the elderly women and an equal percentage of women in the general population attempted to eat a low-calorie diet. Among long-living men, 24 percent consumed alcohol on a daily basis, compared with 22 percent of the general population. And only 43 percent of male centenarians reported engaging in regular exercise of moderate intensity, compared with 57 percent of men in the comparison group.
"In previous studies of our centenarians, we've identified gene variants that exert particular physiology effects, such as causing significantly elevated levels of HDL or 'good' cholesterol," said Dr. Barzilai, who is also professor of medicine and of genetics at Einstein. "This study suggests that centenarians may possess additional longevity genes that help to buffer them against the harmful effects of an unhealthy lifestyle."
The research did find, however, that overweight centenarians tended to have lower rates of obesity than the control group. Although male and female centenarians were just as likely to be overweight as their counterparts in the general population, the centenarians were significantly less likely to become obese. Only 4.5 percent of male centenarians were obese compared with 12.1 percent of controls; and for women, 9.6 percent of centenarians were obese versus 16.2 percent of controls. Both of these differences are statistically significant.
"Although this study demonstrates that centenarians can be obese, smoke and avoid exercise, those lifestyle habits are not good choices for most of us who do not have a family history of longevity," said Dr. Barzilai. "We should watch our weight, avoid smoking and be sure to exercise, since these activities have been shown to have great health benefits for the general population, including a longer lifespan."
But critics argued the individuals themselves had lived healthier lives than others, and it was this that was more important for longevity.
While longevity genes may protect centenarians from bad habits, a vast majority of the population rely heavily on healthier lifestyle choices.
Prof Barzilai emphasized that the research did not mean most people could live unhealthy lives and not expect to pay a price in the end. "Although this study demonstrates that centenarians can be obese, smoke and avoid exercise, those lifestyle habits are not good choices for most of us who do not have a family history of longevity," he told the Telegraph.
"We should watch our weight, avoid smoking and be sure to exercise, since these activities have been shown to have great health benefits for the general population, including a longer lifespan," said Barzilai, noting he was horrified when, after a television appearance, a man addressed him in Starbucks and said he would never exercise again, because his grandmother had lived to 102.
The group of centenarians in the study said they believed good genes were the main reason they were able to live a long life, followed by diet and physical activity. And surprisingly enough, "God, religion or spirituality" did not get much credit, cited by only seven percent of women and 2.5 percent of men in the study.
The US Census Bureau estimates there were nearly 425,000 people aged 95 or older in the US in 2010. That is only a fraction of the 40 million US adults over the age of 65.
On the Net:
- Albert Einstein College of Medicine
- Journal of the American Geriatrics Society
- Longevity Genes Project
- National Health and Nutrition Examination Survey