New research reveals the cause of anemia in space for astronauts

A world-first study reveals how space travel leads to a decrease in the number of red blood cells, known as "space anemia." According to a study published in Nature Medicine, scientists' analysis of the changes in the number of red blood cells in 14 astronauts during a 6-month space mission showed that in space, the number of red blood cells in their bodies is continuously destroyed, and the number of red blood cells destroyed is 54% more than on Earth.

Prior to this study, space anemia was thought to be a rapid adaptation of fluids flowing into the upper body when astronauts first arrived in space, causing the astronauts' blood vessels to lose 10 percent of their fluids. It is believed that in order to restore balance, 10% of the red blood cells in the astronaut's body are rapidly destroyed, while the body's regulation of red blood cells returns to normal after 10 days.

The research team of Dr. Guy Trudel, a rehabilitation physician and researcher at Ottawa Hospital in Canada and a professor at the University of Ottawa, found that the destruction of red blood cells is the main impact of astronauts in space, not just the transfer of body fluids.

On Earth, our bodies produce and destroy 2 million red blood cells per second. The researchers found that astronauts destroyed 54 percent more red blood cells in six months in space, or 3 million red blood cells per second. The results were not related to the gender of the astronauts. The study also found that space-related anemia is reversible, with red blood cell levels gradually returning to normal 3 to 4 months after returning to Earth.

The team repeated the same measurement a year after the astronauts returned to Earth and found that red blood cell destruction was still 30 percent higher than pre-flight levels. These results suggest that the astronaut's physiological structure may have changed in space. After a long space mission, they changed the quality control of red blood cells for up to a year.

This finding has several implications. First, it supports screening of astronauts or space tourists to check for existing blood or health conditions affected by anemia. Second, the longer the space mission, the more severe the anemia, which could affect long-term missions to the moon and Mars. Third, increasing red blood cell production will require an adapted diet for astronauts. (Intern reporter Zhang Jiaxin)

Source: Science and Technology Daily