when people say that, does it anger you? like, "oh shut up".
don't take it for granted. because once the time comes and you realize life isn't forever, your disregard for good health will quickly vanish.
we're only granted one body, take care of it the best you can. eat right and exercise guys. if you abuse it and don't use it, you will lose it.
when you reach that age when bad health habbits begin to take their toll, you will have loved ones you will want to live as long as you possibly can for - so you might as well take action now.
just a thought.