Human lifespan has hit its natural limit, research suggests

Humans are unlikely to ever blow out more than 125 candles on their birthday cake, according to research that suggests that our lifespan has already hit its natural limit.

The oldest human who ever lived, according to official records, was 122-year-old Frenchwoman Jeanne Louise Calment, who died in 1997.

Now a team of American researchers suggest Calment is unlikely to lose the top spot any time soon, as their research shows that though more people reach old age each year, the ceiling for human lifespan appears to be stuck at around 115 years.

“The chances are very high that we [have] really reached our maximum allotted lifespan for the first time,” said Jan Vijg, co-author of the research from the Albert Einstein College of Medicine in New York.

Figures such as Aubrey de Grey, chief scientific officer at the Strategies for Engineered Negligible Senescence (Sens) Research Foundation, have previously claimed that the first person to reach 1,000 years old is likely to be alive today.

But the new study suggests that is highly unlikely. The upshot, says Vijg, is that people should focus on enjoying life and staying healthy for as long as possible. “That’s where we have to invest our money,” he said.

The notion of extending the human lifespan has captured imaginations for millennia. Among scientists, enthusiasm for the idea has grown in recent years with a host of Silicon Valley companies springing up to join academic institutions in attempting to chip away at issue of longevity - among them Google’s California Life Company, or Calico, as it is known – with big-buck prizes such as the Palo Alto Longevity Prize adding to the clamour.

But the researchers, writing in the journal Nature, describe how analysis of records from a number of international databases suggests there is a limit to human lifespan, and that we have already hit it.

Using data for 41 countries and territories from the Human Mortality Database, the team found that life expectancy at birth has increased over the last century. That, says Vijg, is down to a number of factors, including advances in childbirth and maternity care, clean water, the development of antibiotics and vaccines and other health measures.

But while the proportion of people surviving to 70 and over has risen since 1900, the rate of improvements in survival differ greatly between levels of old age. Large gains are seen for ages 70 and up, but for ages 100 or more the rate of improvement drops rapidly. “[For] the oldest old people, we are still not very good at reducing their mortality rates,” said Vijg.

What’s more, in 88% of the countries, the ages showing the greatest rate of improvement have not changed since 1980. 

The researchers then turned to the International Database on Longevity and analysed data from France, UK, the US and Japan - four countries with a high proportion of those aged 110 or above - so-called “supercentenarians”.

Read more https://www.theguardian.com/science/2016/oct/05/human-lifespan-has-hit-its-natural-limit-research-suggests

Courtesy of Guardian News & Media Ltd