What is non-verbal communication? does it indicate our health status at all?

Certainly!: If you look at someone and they are not breathing. That communicates something to you, right? Start CPR! If a person is more pale or more flushed, sweating more than usual, pupils too big or too small, frowning, smiling, shuffling or staggering when walking, or leaping with joy, etc., all those things can communicate a state of mind, a mood, or an illness, even.