After the recent space journey of non-professional individuals, a study suggests that women may be more immune resilient than men to zero gravity.

As the second Frenchwoman, Sophie Adenot, is about to embark on a space journey, a study reveals that the immune system of women may better withstand these trips. Geraldine Zamansky, a journalist at the Health Magazine on France 5, explains the findings.

This discovery was made by a small team of “space tourists”? Indeed. In 2021, for the first time, 4 civilians went into space for 3 days funded by a billionaire. This crew, consisting of two men and two women, underwent numerous examinations before, during, and after their adventure. Blood samples showed changes in immune defenses, even in such a short time. Surprisingly, the cells responsible for fighting infections were more disrupted in the male adventurers. Professor Christopher Mason, who recently published the results of this research conducted at Weill Cornell Medicine in New York in the journal Nature, explains this.

Does a space stay not only damage the bones and muscles of astronauts but also their immune defenses? Professor Mason indeed highlights the dangers of space travel for the human body. The most well-known is zero gravity, which weakens bones and muscles. But the absence of gravity outside also alters our internal balances. Our body contains about 65% water: these fluids move differently in space! To help understand the severity of this change, Christopher Mason uses the image of a cascade. We often talk about the crucial balance of bacteria in the gut, for example, the microbiome. Now, imagine cascading movements that the immune defenses must deal with. It can be quite disruptive. They can also be affected by the toxic radiation from cosmic rays.

Is the body less protected against infections? This is one of the observed effects. Some white blood cells become less capable of detecting a microbe, for example. According to the analysis of the first 4 “space tourists,” this impairment is more significant and longer-lasting in men. The main hypothesis of the researchers is that the female immune system is designed to cope with another incredible internal reorganization: pregnancy. Thus, it may have better adaptive capacities.

In conclusion, this study sheds light on the surprising differences in immune resilience between men and women in space travel. Further research in this field could help improve the health and safety of future space travelers, regardless of gender. It is essential to consider these findings in the planning and execution of long-duration space missions to ensure the well-being of astronauts.