Space exploration exposes astronauts to common forms of radiation on the planet, and is linked to cancer and heart problems, but research in the United States shows that this does not significantly shorten their lives.
The researchers compared nearly 60 years of data on male astronauts in the United States and a group of men who are also more qualified, well-off, and receiving top-quality medical treatment – Peruvian athletes, and found that no group had a higher rate of overall death or premature death. Both groups tend to last longer.
Astronauts are generally educated, richer, physically fit for typical Americans, and some previous studies have linked this career to a lower risk of premature death.
But much of the previous research on mortality rates in astronauts has not been the mental and physical requirements of this career, or the so-called "healthy worker effect" that leads people with employment of any kind, usually have fewer medical problems than people who are unable to work, Research by Robert Reynolds of Mortality Research & Consulting, Inc. in the industrial city of California.
"The challenge was always to understand if the astronauts were as healthy as they would have been if they had used them differently, but they never went into space," Reynolds said in an e-mail. "To do that, we had to find a similar group of several important factors, .
The researchers compared the mortality rates of American astronauts to professional athletes from the Major League Baseball (MLB) and the National Basketball Association (NBA) between 1960 and mid-2018.
Both athletes and astronauts had a lower risk of premature death than the general population. And there was no significant difference in mortality among the NBA and MLB players.
We can not be sure from the data we have, but we speculate that cardiovascular fitness in particular is the most important factor in astronaut longevity.Robert Reynolds –
Astronauts were at higher risk of dying from accidents and other external factors, and were less likely to die from heart disease and all other natural factors, the study found.
"We can not be sure of the data we have, but we speculate that cardiovascular fitness in particular is the most important factor in astronaut longevity," Reynolds said.
More radiation on Mars missions
The results indicate that exposure to radiation in space will not lead to premature death of astronauts due to heart problems or cancer, the authors conclude. In fact, astronauts had a lower rate of death from heart disease than NBA and MLB players, and had a similar cancer mortality rate to athletes.
The study was not designed to prove whether or how space travel may directly affect human health. Nor did she examine the mortality among astronauts or female athletes.
Radiation exposure may also be much lower during the early missions to the moon than reflect what will happen to the current generation of astronauts, said Francis Cochin, a researcher at the University of Nevada, Las Vegas, who was not involved in the study.
"The missions in the past were low-dose, while the dosage would be 50 to 100 times higher for Mars's mission," Cucinotta said by email.
Astronauts generally do not smoke, which leads to a lower risk of heart disease than the general population, said Cucinotta.
Diet and exercise also put astronauts and professional athletes aside from the rest of the population, said Michael Delf, a researcher at Florida State University in Tallahassee who was not involved in the study.
"When physical fitness is a necessary part of a job, as with professional astronauts and athletes, this is a crucial factor in the healthy worker effect," Delf said in an e-mail.
Even for all of us, "Staying or being physically active and maintaining a well balanced diet significantly improve overall health and well-being, and can improve successful aging," Delp advised.