Post by Bozur on Nov 13, 2005 14:11:32 GMT -5
For Centenarians, It All Begins at Birth
By HENRY FOUNTAIN
Published: October 30, 2005
CENTENARIANS are different from the rest of us, and it's not just that they are a lot older. They are a select group, having persisted through wars, diseases, disasters and accidents that kill tens of millions of ordinary mortals every year.
Leo Espinosa
www.agingresearch.org/calculator/
Longevity Calculator (Alliance for Aging Research)
In looking at what makes a 100-year-old so special - fewer than 2 in every 10,000 Americans live to that age or older - those who study aging cite factors like genetics (particularly having two X chromosomes, as 85 percent of centenarians are women) and environmental influences like good nutrition and health habits.
But a statistical study of centenarians by researchers at the University of Chicago has found some other potential predictors of extreme longevity. Women and men who were the first born in large families, the study found, were two to three times more likely to make it to 100 than later-born children. Those raised in the rural West had a better chance of reaching that age. And people of advanced age who were born in October and November had longer life expectancy than those born in April through June.
So if you are a fall baby, the first child of a farming couple from Boise, are you a safe bet to make it to 100?
Hardly, experts say. Factors like birth order and birth month play a small role, at best, in the likelihood of reaching advanced age, and are overwhelmed by others.
"You have to remember, this is for populations, not for individuals," said S. Jay Olshansky, a professor in the school of public health at the University of Illinois at Chicago, commenting on the study. "For an individual, the month you were born is going to be largely irrelevant. What really will matter is the lifestyle you lead and the genetics you inherited."
Still, odd predictors like birth month may say some interesting things about what makes one person live so long.
"In the case of birth order, we were really surprised," said Leonid A. Gavrilov of the National Opinion Research Center at the University of Chicago, who with his wife, Natalia S. Gavrilova, sifted 75 million computerized genealogical records to identify centenarians born from 1875 to 1899, and then consulted Social Security death records and census data to find more about the circumstances of their lives. The study was prepared for the Society of Actuaries.
Other studies of different age groups have shown that birth order can be a factor. "There are a lot of observations that first-born children have an advantage both in health status and even in educational achievement," Mr. Gavrilov said.
What may improve the chances of first-borns reaching 100 is that in general they are born of relatively young parents. Sperm and eggs can become damaged over time, so children of older parents may have more health problems related to genetics.
Similarly, birth month, which has also been correlated to life expectancy in other studies, may be an indication of seasonal vitamin deficiencies or seasonal illnesses like flu or diarrheal diseases that affect childhood health, with an impact later in life.
In the United States, those health problems were more serious a century ago, when current centenarians were born, than now, when foods are fortified, fresh vegetables are available year round, vaccines are commonplace and sanitation is improved.
"Those are things that we just wouldn't experience these days," said Thomas Perls, a professor at Boston University Medical Center and director of the New England Centenarian Study. "That was a time when people lost a quarter of their kids to childhood illnesses."
So birth month, even if it had some importance in the late 19th century, may no longer have much of a role in longevity. If so, those who study the very old will have plenty of chances to find out, since the number of centenarians is booming. From the approximately 50,000 centenarians counted in the 2000 census, demographers expect the number to soar; one census estimate is that there will be about 800,000 by the middle of the century.
Whatever the number, Mr. Olshansky said, centenarians are going to seem less extraordinary as improvements in medicine and other factors make it easier to live longer. "Centenarians today had to survive an incredible array of environmental insults and infections that make them a much more highly selected group of individuals than we're going to see in the future," he said.
Dr. Perls likened living to 100 to winning the lottery. "Say you need six numbers," he said. One may be not being obese, one being a woman, another not getting heart disease, and the like.
"In the past, we've left all these lottery numbers up to chance," Dr. Perls said. Now, through better health care and other improvements, he said, "we're doing a better job of predetermining those numbers.
"It's much more easy to win the lottery than it was."
By HENRY FOUNTAIN
Published: October 30, 2005
CENTENARIANS are different from the rest of us, and it's not just that they are a lot older. They are a select group, having persisted through wars, diseases, disasters and accidents that kill tens of millions of ordinary mortals every year.
Leo Espinosa
www.agingresearch.org/calculator/
Longevity Calculator (Alliance for Aging Research)
In looking at what makes a 100-year-old so special - fewer than 2 in every 10,000 Americans live to that age or older - those who study aging cite factors like genetics (particularly having two X chromosomes, as 85 percent of centenarians are women) and environmental influences like good nutrition and health habits.
But a statistical study of centenarians by researchers at the University of Chicago has found some other potential predictors of extreme longevity. Women and men who were the first born in large families, the study found, were two to three times more likely to make it to 100 than later-born children. Those raised in the rural West had a better chance of reaching that age. And people of advanced age who were born in October and November had longer life expectancy than those born in April through June.
So if you are a fall baby, the first child of a farming couple from Boise, are you a safe bet to make it to 100?
Hardly, experts say. Factors like birth order and birth month play a small role, at best, in the likelihood of reaching advanced age, and are overwhelmed by others.
"You have to remember, this is for populations, not for individuals," said S. Jay Olshansky, a professor in the school of public health at the University of Illinois at Chicago, commenting on the study. "For an individual, the month you were born is going to be largely irrelevant. What really will matter is the lifestyle you lead and the genetics you inherited."
Still, odd predictors like birth month may say some interesting things about what makes one person live so long.
"In the case of birth order, we were really surprised," said Leonid A. Gavrilov of the National Opinion Research Center at the University of Chicago, who with his wife, Natalia S. Gavrilova, sifted 75 million computerized genealogical records to identify centenarians born from 1875 to 1899, and then consulted Social Security death records and census data to find more about the circumstances of their lives. The study was prepared for the Society of Actuaries.
Other studies of different age groups have shown that birth order can be a factor. "There are a lot of observations that first-born children have an advantage both in health status and even in educational achievement," Mr. Gavrilov said.
What may improve the chances of first-borns reaching 100 is that in general they are born of relatively young parents. Sperm and eggs can become damaged over time, so children of older parents may have more health problems related to genetics.
Similarly, birth month, which has also been correlated to life expectancy in other studies, may be an indication of seasonal vitamin deficiencies or seasonal illnesses like flu or diarrheal diseases that affect childhood health, with an impact later in life.
In the United States, those health problems were more serious a century ago, when current centenarians were born, than now, when foods are fortified, fresh vegetables are available year round, vaccines are commonplace and sanitation is improved.
"Those are things that we just wouldn't experience these days," said Thomas Perls, a professor at Boston University Medical Center and director of the New England Centenarian Study. "That was a time when people lost a quarter of their kids to childhood illnesses."
So birth month, even if it had some importance in the late 19th century, may no longer have much of a role in longevity. If so, those who study the very old will have plenty of chances to find out, since the number of centenarians is booming. From the approximately 50,000 centenarians counted in the 2000 census, demographers expect the number to soar; one census estimate is that there will be about 800,000 by the middle of the century.
Whatever the number, Mr. Olshansky said, centenarians are going to seem less extraordinary as improvements in medicine and other factors make it easier to live longer. "Centenarians today had to survive an incredible array of environmental insults and infections that make them a much more highly selected group of individuals than we're going to see in the future," he said.
Dr. Perls likened living to 100 to winning the lottery. "Say you need six numbers," he said. One may be not being obese, one being a woman, another not getting heart disease, and the like.
"In the past, we've left all these lottery numbers up to chance," Dr. Perls said. Now, through better health care and other improvements, he said, "we're doing a better job of predetermining those numbers.
"It's much more easy to win the lottery than it was."