Ur Eyes will water at my incredible bite. What am I ?

Size of my fist or size of dust,
Color of night, rainbow or white
If I check health,
I'm unhealthy myself.
I can be hot.
Ur eyes will water,
At my incredible bite.

What am I?

Click here for Answer

Pepper (Pepper fruit/grain, red/green/yellow/black/white pepper, Dr Pepper, Chili Pepper and Pepper spray)