Characteristics of Centenarians
A study by the Boston University School of Medicine found that centenarians varied widely in years of education (zero years to post-graduate), socioeconomic status (very poor to very rich), religion, ethnicity and patterns of diet (strictly vegetarian to extremely rich in saturated fats), they found a number of characteristics in common:
• Few centenarians are obese. In the case of men, they are nearly always lean.
• Substantial smoking history is rare.
• Centenarians may be better able to handle stress than the majority of people.
• Not all centenarians show signs of dementia, and some had healthy-appearing brains.
• A woman who naturally has a child after the age of 40 has a four times greater chance of living to 100 compared to women who do not. A late pregnancy may be an indicator that the woman’s reproductive system is aging slowly and that the rest of her body is as well.
• At least 50 percent of centenarians have first-degree relatives and/or grandparents who also achieve extremely old age, and many have exceptionally old siblings. Male siblings of centenarians have a 17 times greater chance than other men born around the same time of reaching age 100, and female siblings have an 8.5 times greater chance than other females born around the same time of achieving age 100.
• Many of the children of centenarians (age range of 65 to 82) appear to be following in their parents’ footsteps with marked delays in cardiovascular disease, diabetes and overall mortality.
• Some families demonstrate exceptional longevity that cannot be due to chance and must be due to familial factors.
• The offspring of centenarians, compared to population norms, score low in neuroticism and high in extraversion.
The Role of Genes Versus Environment
Scientists have long debated the role of nature versus nurture: Studies of identical twins reared apart, for example, have shown 70–80 percent environmental influence and 20-30 percent genes. However, the New England Centenarian Study discovered that exceptional longevity (living over the age of 100) runs strongly in families. Other study results strongly suggest that the genetic component of exceptional longevity gets larger and larger with increasing age and is especially high for those age 106 years and older. The New England study was particularly interested in how centenarians are able to markedly delay, or in some cases escape, Alzheimer’s disease.
Researchers performed detailed and annual neuropsychological examinations on centenarians in the Boston area. The study concluded that most people have the genetic makeup to live into their mid- to late 80s in good health, and like centenarians, compress the time they are sick toward the end of their lives. Much of their ability to do so depends upon healthy behaviors, including not smoking, strength-training exercise and a diet conducive to being lean. Other studies have found that a sense of humor, playing music and a strong social system contribute to living over 100.
Recent Scientific Breakthroughs Science is making discoveries that could keep people living even longer than 100-plus. In March, Science magazine announced that a team led by an Australian researcher found that targeting a single anti-aging enzyme in the body has the potential to prevent age-related diseases and extend lifespan. This means that a whole new class of anti-aging drugs could ultimately prevent cancer, Alzheimer’s disease and Type 2 diabetes.
“The target enzyme, SIRT1, is switched on naturally by calorie restriction and exercise, but it can also be enhanced through activators. The most common naturally-occurring activator is resveratrol, which is found in small quantities in red wine, but synthetic activators with much stronger activity are already being developed.”
In May, a team of 70 scientists from the United States, China, Australia and Japan reported that it sequenced and annotated the genome of the lotus plant, which is believed to have a genetic system that repairs genetic defects and may hold secrets about aging successfully (“Research may help scientists learn anti-aging secrets of sacred lotus,” Medical.net).
“The lotus genome is an ancient one, and we now know its ABCs,” says Jane Shen-Miller, one of the researchers and a senior scientist with UCLA’s Center for the Study of Evolution and the Origin of Life. “Molecular biologists can now more easily study how its genes are turned on and off during times of stress and why this plant’s seeds can live for 1,300 years. This is a step toward learning what anti-aging secrets the sacred lotus plant may offer.”
Longevity research seems to be increasingly aimed not at getting people to live longer but, if they are going to live longer, to stay healthy. In the New England study, nonagenarians (subjects in their 90s), centenarians (ages 100–104), semi-supercentenarians (ages 105–109) and supercentenarians (ages 110+) had progressively shorter periods of their lives spent with age-related diseases. These findings support the hypothesis, known as the compression of morbidity, that as one approaches the limits of lifespan, diseases (morbidity) must be delayed (or escaped) toward the end of these longest lived, and that there truly is a limit to human life span and that this limit is around 110–125 years.
Despite this finding, the field of increasing our lifespan, known as life extension science, is a large one and appears to be growing.