I want to begin by making it clear that I shower at least once per day, wear deodorant at all times, and while I am not a neat freak, I take care of my personal hygiene. I am asking this question out of curiosity, not in an attempt to justify being filthy.
I would imagine that humans have been in the habit of bathing frequently for a relatively short period of time, and that prehistoric humans rarely, if ever, bathed their entire bodies, and only washed specific parts of their bodies when it was actually necessary (i.e., if they had to remove mud, blood, etc).
Even today, we tend to bathe for reasons that have nothing to do with health. We do it out of habit, and for social reasons (e.g., not wanting to smell bad). These are aesthetic and cultural motivations, not related to health.
To be clear, I am not asking about washing hands, which obviously does have positive effects; I am interested in the question of whether bathing the entire body is beneficial or detrimental.
Is there any health benefit or detriment, whether related to skin health, hair care, internal health, or anything else, from bathing the entire body?