Every second on Earth, 2 million red blood cell are created and destroyed by our bodies. In a new study published today in the journal Nature Medicine, a team of scientists from the Ottawa Hospital Research Institute and the University of Ottawa found that astronauts were destroying 54% more red blood cells during their 6-month missions onboard the International Space Station, or 3 million every second.
Trudel et al. The destruction of red blood cells, known as hemolysis, is a primary effect space flight microgravity. This supports the idea that space tourist anemia should be taken into account when screening them. NASA image credit.
“Space Anemia has been consistently reported by astronauts returning to Earth from the first space missions. But we don’t know why,” stated Professor Guy Trudel. He is a rehabilitation physician and researcher at Ottawa Hospital Research Institute and University of Ottawa.
“Our study shows that upon arriving in space, more red blood cells are destroyed, and this continues for the entire duration of the astronaut’s mission.”
Before the new study, it was believed that space anemia was a quick adaptation to fluids moving into the astronaut’s upper bodies when they first arrived in orbit.
The authors discovered that red blood cell destruction is a primary consequence of being in space and not caused by fluid shifts.
They demonstrated this by directly measuring red blood cell destruction in 14 astronauts during their six-month space missions.
” “Having fewer red blood cells per square inch isn’t an issue when your body is weightless,” Professor Trudel stated.
“But when landing on Earth and potentially on other planets or moons, anemia affecting your energy, endurance, and strength can threaten mission objectives.”
” Anemia is only felt when you land. You must then deal with gravity again .”
In the study, five out of 13 astronauts were clinically anemic when they landed — one of the 14 astronauts did not have blood drawn on landing.
The researchers saw that space-related anemia was reversible, with red blood cells levels progressively returning to normal three to four months after returning to Eart