Dear friend, you can smoke less to make the whites of your eyes whiter. We know that the smokes can tint the whites of our eyes and make our eyes look yellow. But the yellow on the whites of our eyes will disappear slowly if we smoke less or give up smoking. Don't worry. This will not affect your vision.
I will suggest you to give up smoking too. The smokes will tint the whites of our eyes and make our eyes yellow. My father is a heavy smoker. He often smokes in the bedroom and tint the white wall of the room. My mother has yellow spots on her whites of eyes. I think it is caused by smokes. So I suggest my father to smoke in the outside and smoke less during the night.