Have we reached our peak longevity?

The oldest of humanity, Frenchwoman Jeanne Calment, lived to be 122 years old. What are our chances of living that long? Weak, unless there is a transformative medical breakthrough, reveals a study published Monday in the journal Nature Aging.

The study analyzed data from 1990 to 2019 on life expectancy at birth, in the countries where people live the oldest, namely Australia, South Korea, France, Hong Kong, Italy , Japan, Sweden, Switzerland and Spain. We also included the United States, although life expectancy is lower there.

Although average life expectancy increased during these 29 years in all countries, the rate of increase slowed, except in Hong Kong.

After decades of medical and technological advances that have us living longer and longer, the human race may be approaching its maximum average lifespan, researchers say.

According to him, maximum life expectancy will stabilize around 87 years – 84 years for men and 90 years for women – an average which several countries are already approaching.

During the 20th^e century, life expectancy has increased dramatically, thanks to advances like clean water and antibiotics. Some scientists believed that this rate would continue with future treatments (and prevention) of cancer, cardiovascular disease, and other deadly illnesses. Demographer James Vaupel believed that most children born in the 21st^e century would live to be 100 years old.

However, according to the new study, that will not happen. Instead of finding a higher percentage of centenarians, the researchers found a plateauing of longevity below 100 years.

Long-time skeptic

Mr. Olshansky never believed in the idea of ​​ever-increasing life expectancy. From 1990, in the magazine Sciencehe presented his theory that the human race was already nearing its maximum average life expectancy.

Today, 34 years later, his concrete data supports his theory. Even those who disagreed with him now concede merit.

In 2000, Steven Austad, a biology professor at the University of Alabama, bet Mr. Olshansky $150 that a human being alive at the time would reach the age of 150 (the money is in a investment funds). They even increased the stake to $600 in 2016. However, Mr. Austad recognizes that the article published Monday is “excellent” and “establishes without a shadow of a doubt” that the increase in life expectancy slowed down.

Jan Vijg, professor of genetics at the Albert Einstein College of Medicine in New York, who has also conducted studies on this subject, believes that Mr. Olshansky’s study is “well done.”

“Mr. Olshansky has always been considered a pessimist, but in my opinion he is also a realist,” says Jan Vijg.

According to the new study, modern medicine has allowed many humans to live to be 70, 80 and 90 years old, but it will be difficult to go much further. So, even if all deaths before age 50 are excluded from the data, the maximum average life expectancy only increases by one year for women and one and a half years for men.

“We can squeeze a little bit more into survival thanks to advances in medicine,” by reducing disparities in care and encouraging healthier lifestyles, Mr. Olshansky says.

But even if deaths from common illnesses or accidents were eliminated, people would die of old age: “The decline in organ function […] makes it virtually impossible for the body to live much longer than it does today,” says Olshansky.

Not everyone agrees. According to the D^r Luigi Ferrucci, scientific director of the National Institute on Aging, says lifespan is unlikely to increase much if nothing changes. On the other hand, investing in prevention can be a game-changer by delaying the onset of diseases, which, in turn, could lead to “reduced damage due to the biology of aging.”

Nadine Ouellette, associate professor of demography at the University of Montreal, disputes another aspect of the study. According to her, average life expectancy can “sometimes be misleading” because it is strongly influenced by deaths occurring early in life. Instead, she recommends looking at the age at which most people die, called the modal age at death, which looks more at the end of life.

Medical breakthrough to come?

Olshansky believes that only one thing could radically extend life expectancy: a medical breakthrough that would slow the aging process itself. On this subject, he says he is “optimistic”.

Mr. Austad also believes in the potential of anti-aging medicine. Besides, he still believes that a human alive today will reach 150 years old. He thinks that the study published on Monday does not change his chances of winning his bet, because it has always been based on “a breakthrough against aging itself”.

This article was published in the New York Times.

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