"In Space, Aging Slows Down"... Aging Delayed but Reaction Speed Drops Sharply

SOMA Project Analyzes Astronaut Health
'Aging-Related' Telomeres Lengthen in Space
Women Recover Faster After Returning to Earth

A study has revealed that the human body placed in the space environment undergoes rapid changes in just three days. While the aging process slowed down significantly in space, the body showed notable changes such as decreased bone density, reduced muscle strength, and slower reaction times. With the advent of a civilian-led space aviation era, related research is expected to continue.

Recently, the international joint project 'SOMA (Space Omics and Medical Atlas),' led by the Weill Cornell Medical College in the United States, analyzed the effects of the space environment on health by studying civilians who went on space tourism and astronauts who stayed on the International Space Station (ISS). The findings were published in the international academic journals Nature and Nature Communications.

SOMA is a project that analyzes and digitizes physiological changes in living organisms in the space environment. The research team analyzed medical data from four civilian astronauts who toured space through SpaceX's civilian space project 'Inspiration4' and 64 astronauts who stayed on the ISS for six months to one year. This is the largest project to date analyzing astronaut health.

In 2021, SpaceX became the first in the world to send four civilians aboard the manned spacecraft Crew Dragon to an altitude of 585 km. They stayed in space for three days before returning to Earth. The researchers collected blood, urine, feces, and saliva samples from the four individuals to analyze bodily changes. The New York Times (NYT) evaluated the study results by stating, "Three days in space was enough to change the bodies and minds of the four civilian astronauts."

The most notable change was that the 'telomeres,' genes known to regulate the aging process, lengthened in space. Telomeres protect genes from damage, and longer telomeres mean cells age more slowly. All four civilians experienced telomere lengthening in space. However, after returning to Earth, their telomere lengths reverted to previous levels, and some even showed shortened telomeres, suggesting a potential acceleration of aging. The researchers speculate that the lengthening occurred as a result of repairing telomeres damaged by radiation.

Research also indicated a higher likelihood of kidney stone formation due to molecular changes in the kidneys in space. Although the four civilians who toured space on Inspiration4 stayed only three days, the researchers believe that longer stays could lead to kidney stone problems, necessitating the development of treatment methods. Bone density decreased, muscle strength declined, and the immune system showed temporary instability.

Additionally, astronauts exhibited significantly slower reaction times while in space. Both civilian astronauts and professional astronauts participated in various cognitive tests using iPads to measure cognitive function in space. One test involved suddenly displaying a stopwatch on the screen and measuring the time taken to tap it, which was slower than on Earth. The NYT described this as a "temporary cognitive decline." Another related study found decreases in visual search ability and working memory.

After experiencing these physical changes, the four civilian astronauts recovered in their daily lives upon returning to Earth. Most of their bodies returned to pre-spaceflight conditions. Recovery was faster in women; the two female astronauts in Inspiration4 returned to their previous health states more quickly than the two male astronauts. The researchers interpreted this as women’s greater flexibility in enduring changes and stress, such as those experienced during space travel, possibly due to their reproductive capabilities.

As interest and investment in civilian space tourism grow, such research is expected to accelerate. Afshin Beheshti, a researcher at NASA Ames Research Center, said, "This study has gradually allowed us to find correlations in bodily changes. The puzzle pieces are beginning to come together, which will make it easier to establish countermeasures."