Look . . . in . . . the . . . dictionary.
A dictionary is an attempt to define a word using other words. There is an inherent problem with this in that not all words can be defined using other words.
And as I already pointed out to you in the definition, the word used is tending to promote health. And there is a reason the dictionary used "tending", because it means something akin to "leaning towards"
"He tends to be more liberal than conservative."
This does not mean he is completely liberal.
Just like hygiene does not mean it must promote health to fall in the category of hygiene. Indeed, what exactly promotes health is questionable.
Having lived speaking English for 33 years, and being quite good at it, might I add, as well as having read extensively my whole life, including dozens if not hundreds of college level texts, I know how to use the word "hygiene" correctly.
Yes it is, but hygiene was also correct. I could have said it is just basic grooming, but I didn't, because that word was not on the tip of my tongue.AE's suggestion of grooming is appropriate.