How old can you get?
DON’T EXPECT OUR LIFESPANS TO GET ANY LONGER
SHE IS NOT MERELY THE ONLY VERIFIED 122-YEAR-OLD IN HUMAN HISTORY; SHE IS STILL ITS ONLY 121-YEAR-OLD AND ITS ONLY 120-YEAR-OLD. — COLUMNIST COLBY COSH
Do you remember Jeanne Calment, the French woman who lived to be 122 years old? The Arlésienne died in 1997; as the person who lived to the greatest verifiable age, she enjoyed an unusually long time in the media spotlight as the senior member of our species. She is remembered for having sold pencil crayons to Vincent van Gogh, whom she remembered as “dirty” and “disagreeable,” and for having smoked cigarettes for 96 years, surely a record in itself.
I am sure you probably do remember Jeanne Calment if you are old enough. Stories of what gerontologists call “supercentenarians” — people who breeze past their 110th birthdays — have been clickbait since before we called it that. Today’s quasiofficial oldest living person is Emma Morano, a chatty, ambulatory Italian scheduled to turn 117 on Nov. 29. There are, as always, other contenders, whose families insist they are older. But for now, Morano is the last identifiable human alive who was definitely born in the 1800s.
Since Jeanne Calment died, supercentenarian research, once left mostly up to the Guinness Book of Records, has gained an organized framework, much as baseball history did when publishers started compiling statistical encyclopedias. There are now multiple international groups working to collect, validate and study extreme lifespans. If you are an enthusiast of this subject, this has gradually turned Calment from a sly, wonderful curiosity, into something more sinister — a figure standing at the gates of the afterlife, taunting us.
It would be natural to expect her lifespan record to have been challenged and beaten sometime in the last two decades. Instead, she remains supreme, a Beamonesque outlier. She is not merely the only verified 122-year-old in human history; she is still its only 121-year-old and its only 120-year-old.
The international Gerontology Research Group (GLG), founded at the University of California, Los Angeles, and now a worldwide network of pro-am age detectives, maintains a table of all confirmed supercentenarians.
As often happens with mass death data of any kind, it is upsettingly regular in shape. The most recent version of the table, updated on New Year’s Day 2014, lists 764 people confirmed from good public records and other corroborating information to have died at the age of 110. At 111, the number drops to a little more than half that: 416 people. At 112, the number drops again by a bit less than half. By the time we reach age 117, there are only two people. There is one 119-year-old in the table, Sarah (Clark) Knauss (1880-1999) of Pennsylvania. Beyond that, there’s only Jeanne Calment, defying all challengers.
A new study in Nature magazine, performed by number-crunchers from the Albert Einstein College of Medicine in New York, delves deeper into mortality statistics and confirms the troubling picture of a possible inherent, or at least very intractable, limit to human lifespan.
The overall human life expectancy — the mean amount of time an average person may expect to live — increased rapidly throughout the past century, with downturns that coincided with global wars. It is still rising impressively. The largest gains were, at first, accounted for by public-health improvements like plumbing and antibiotics, which had their biggest impact among babies and children. Then, medicine in the developed countries started solving the more complex ills of the middle-aged and elderly.
The Einstein College doctors made a plot of the age at which people in each calendar year experienced the biggest gains in life expectancy. They document that in the countries with the best health care and the best mortality data, that age is now well above 100. In Canada — as well as Denmark, Japan, Sweden and other developed countries — the line marking the age of greatest survival benefit plateaued around 1980 at about 104 for both sexes, and it is stuck there.
Going forward, countries like ours can expect to have many more centenarians, and they will be in ever better health. But so far, we have not succeeded in increasing the life expectancy of supercentenarians to any significant degree. A separate analysis, taken from the GLG’s data and other similar data sets, suggests that the highest attainable age is not rising over time and may, if anything, be in decline.
These inferences are taken from fairly small samples, and the dismal message is obviously subject to a sudden breakthrough in the understanding of human aging. But that is the whole point: such breakthroughs have been arguably quite late in arriving. The very old still often die without an attributable cause, as Calment did.
Most gerontologists are now pretty sure that human cells or genes do not harbour evolutionary switches, “deliberately” installed by nature, that shut us off to make room for descendants. But they are still not collectively certain whether aging is, at the extremes, a matter of entropy — of the natural tendency for organized matter to fall apart — or of concealed diseases that might be treatable. Of course, I still personally hope to look back on that sentence in the year 2500 and laugh …