Humans may not have reached their lifespan limit

A new way of analyzing mortality records suggests that the maximum human lifespan has not yet been reached and could start to rise in the coming decades. While human life expectancy has been increasing for decades in most countries, the record for the oldest living person has not been increasing. However, researchers from the University of Georgia in Athens found that people born after about 1910 have a lower risk of dying in any given year as they age, suggesting that the world record for the longest-lived person will increase as surviving members of these cohorts reach advanced old age. The researchers analyzed the age of death in groups of people who were born in the same year, rather than grouping people according to their year of death, which can obscure trends. The study’s lead researcher, David McCarthy, says people in these birth cohorts have benefited from improvements in medicine since the end of the second world war, but we cannot predict how long that trend might continue. Some scientists, such as Jan Vijg at the Albert Einstein College of Medicine in New York, have previously concluded that there is probably a biological limit on the maximum human lifespan, which he puts at about 115 years old. But Kaare Christensen at the University of Southern Denmark says there is good support from previous studies that the risk of death per year, which for most of our lives rises exponentially with age, starts to plateau after people reach about 105. Whether the maximum human lifespan will start to rise in the coming decades remains uncertain, as many projects hinge on models that predict what will happen in the future.