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Space Anaemia


Since the beginning of crewed flights, astronauts have returned from space with anaemia, a condition in which the body does not produce enough red blood cells to transport oxygen to the body's tissues. In a healthy adult human body there are more than 35 trillion red blood cells.

Anemia is only one of the health challenges that astronauts face. Health professionals were baffled as to how this occurred, but a recent research published in Nature financed by the Canadian Space Agency (CSA) shows the factors that lead to this potentially dangerous illness.

Every second, at least 2 million red blood cells are generated and hemolyzed (or destroyed).

However, in space, over 3 million red blood cells are lost every second, leading astronauts to lose approximately 54% more blood cells than they would on Earth. Trudel's research shows that this process does not end in space, but that the anaemia persists for the following six months. According to a recent research, the effects last long even after astronauts return to Earth.

This phenomenon, known as space anaemia, Is not new it was previously known to scientists, but they anticipated it to resolve over time as astronauts' bodies adapted to the space environment. For the first time, the new research proved that this is not the case, a discovery that might have major ramifications for long-term space flight.

Astronauts are loosing 3 million red blood cells every second in space

Scientists believe it's because of how microgravity affects bone marrow. MARROW, a Canadian experiment that was recently sent to the International Space Station, has investigated the consequences.

If you have less red blood cells, you may be more quickly exhausted and have diminished strength, cognitive capacity, and cardiac function, said Dr. Guy Trudel, a professor at the University of Ottawa in Canada, who led the study.

Furthermore, if red blood cell production is insufficient, crew members may be unable to respond adequately to a bleeding accident. They would also struggle to execute responsibilities if they returned to a gravitational environment, such as landing on Mars or returning to Earth.


As humanity prepares interplanetary travel, it will be vital to understand the health consequences of space flight in order to design safe missions. One critical component of such comprehensive studies is determining if astronauts' bone marrow composition and blood cell production can be restored to pre-flight levels when they return to Earth or land on another planet.

The findings from such studies may aid in the development of specialised countermeasures, such as exercise,as well as pharmacological or genetic therapies and preventative interventions.


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