NASA and Soviet studies on hygiene in preparation for space station missions do not support this conclusion,[28] and no mechanism of action for how the sebaceous glands below the skin detect sebum levels in hair has been proposed.
The given reference #28 seems to be chapter 10 of Packing for Mars... I can't find anything in that book chapter which matches the claim made in the Wikipedia article that no poo and specifically the reduction in sebum has been debunked by both NASA & Russia. The closest passage seems to be
...The head in general is a proble
This is the public group instrumental rationality diary for May 1-15.
Thanks to cata for starting the Group Rationality Diary posts, and to commenters for participating!
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