Driven by technological progress, human life expectancy has increased greatly since the nineteenth century. Demographic evidence has revealed an ongoing reduction in old-age mortality and a rise of the maximum age at death, which may gradually extend human longevity1,2. Together with observations that lifespan in various animal species is flexible and can be increased by genetic or pharmaceutical intervention, these results have led to suggestions that longevity may not be subject to strict, species-specific genetic constraints. Here, by analysing global demographic data, we show that improvements in survival with age tend to decline after age 100, and that the age at death of the world’s oldest person has not increased since the 1990s. Our results strongly suggest that the maximum lifespan of humans is fixed and subject to natural constraints.
We thank T. Wang for his suggestions on the statistical analysis. This study was supported by grants from the NIH to J.V. (AG017242 and AG047200), the Albert Einstein College of Medicine Institute for Aging Research/Nathan Shock Center, and the Paul F. Glenn Center for the Biology of Human Aging at the Albert Einstein College of Medicine.