The New York Times asks whether a person could live to 200: in 2000 the biologist Austad predicted that the first person to reach 150 is probably already alive; the gerontologist de Grey gives today's 40-year-old a better than 50% chance of never dying of old age; the epidemiologist Olshansky says a promise of 50 extra years would take 50 years to check
The New York Times asks whether a person could live to 200: in 2000 the biologist Austad predicted that the first person to reach 150 is probably already alive; the gerontologist de Grey gives today's 40-year-old a better than 50% chance of never dying of old age; the epidemiologist Olshansky says a promise of 50 extra years would take 50 years to check
On October 14, Christie Aschwanden published an article that asks how realistic such forecasts are.
In 2000 the biologist Steven Austad said: "The first 150-year-old person is probably alive right now." The epidemiologist Jay Olshansky bet $150 that Austad was wrong. The gerontologist Aubrey de Grey holds that there is a better than 50% chance that a person who is 40 today will never die of old age.
The record for documented age has stood since 1997, when Jeanne Calment died at 122 (her age is disputed). "Since then nobody has lived even to 120," says Austad himself.
In 2024 Olshansky and his coauthors reported in Nature Aging that in the eight longest-lived countries, Hong Kong and the United States, gains in life expectancy during the 2010s were smaller everywhere than in the 1990s. The authors conclude that life expectancy is approaching a "soft" limit, one that could be moved by changing the rate of biological aging. They see grounds for expecting a "second longevity revolution" in efforts to slow aging. However, as long as the rate of aging in humans cannot be changed, radical life extension within this century remains implausible.
Jamie Justice, executive director of the XPRIZE Healthspan competition for extending healthy life, describes aging as the point at which the body stops repairing damage as fast as the damage accumulates. Scientists have identified about a dozen hallmarks of aging. Some resemble wear and tear: with every cell division the telomeres, the protective ends of chromosomes, get shorter, and once they become too short the cell stops dividing. Others involve cells in a "zombie state", which do not die but stop working properly; some of these cells release substances that sustain inflammation.
In laboratory animals researchers can slow some of the processes of aging, says John Newman of the Buck Institute for Research on Aging. Senolytics, a class of experimental drugs, are meant to clear out the cells in the "zombie state". Epigenetic reprogramming changes the marks on DNA that switch genes on and off, so that cells behave as if they were younger; companies are already testing drugs based on this approach.
Most longevity research aims at healthy life up to the age of 80 to 100. A promise to extend life itself can only be checked by waiting: "If someone says they have something that will let you live 50 years longer, you will have to wait 50 years to find out whether it is true," Olshansky explains. The bet works the same way: the money goes to the winner or the winner's descendants only in 2150. Austad is trying to shorten this kind of wait: in September he and his colleagues proposed 12 measures of the rate of aging that should reveal a slowdown of aging in mice sooner.
Coleen Murphy of Princeton University describes aging as a set of interacting systems: "If you fix one, there is always another." Kidneys, hearts and knees are already being replaced, but "some cells cannot regenerate," Murphy says, and these include most muscle cells and brain cells.
The brain, according to Austad, poses a particular difficulty: most people will not want to live past 100 unless their mind stays intact. If a new brain were transplanted, it is unclear whether the person would still be the same person. The bet sets the same condition: Austad wins only if the 150-year-old is of sound mind.