When they create the successor to the ISS, they should throw a little dirt in there https://phys.org/news/2025-02-iss-overly-sterile-dirtier-astronaut.html

The Farcaster formerly known as Kchamp. Books, beats, bodybuilding, bright ideas and beautiful things.

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Most of the root causes of inflammatory surge in space comes from a degradation in mitochondrial performance and instability of mRNA. Also degrade NK cell function (macrophages go defunct). 
Now with the sterility, you basically wipe out any beneficial bacteria. 
(Reason for doing the sterility is that some microbes like Salmonalla I think are more pathogenic in space.)
“Like this study showed, it also increases IL-6 levels hence more inflammatory.

You can add beneficial microbes, but problem is that most either degrade or lead to biofilms and more virulent. 

Notable mentions have been deinococcus as an option and also engineered lactobacillus comparing ‘artificial dirt’. Also targeted immunomodulators (Quercetin, natural killer cells stabilizers) are on the horizon, think of them like pre-space shots similar to when going to a region with meningitis.

Dr Omar is a member of the Aerospace Medical Association and has amazing insight on this in the replies

Dr Omar is a member of the Aerospace Medical Association and has amazing insight on this in the replies https://warpcast.com/dromar.eth/0x0700bed3