https://www.iconfinder.com/icons/2740474/personal_protection...
hope i did convey the idea.
edit: You should probably use a icon like this one https://www.iconfinder.com/icons/830113/character_figure_man... for the person instead the one i linked, since showing only the head instead of the entire body is not very clear (i used that one only for explain the emblem idea)
But even without the text it still has some problems, since without context you may think it mean body hydratation level or blood, unless you use colors (yellow, blue and red ) to distinguish between them, but even then, they are not always available/possible and pose accessibility problems, for visually impaired (is the correct word?) etc...
you could also use the text, if you target a specific locale, or also localizing the icons may make sense.
Since i don't know where this icons will be used i don't know what the best solution and i don't have a perfect solution.
I hope I have explained myself better.
edit: grammar
The context is for a fitness app.