I've been told Saif's fine. Stress is a part and parcel of our lives. The only way to cut down on stress is to not think too much about it and balance your time well.
People other than actors also lead stressful lives — even getting an education is stressful today! You have to cope and take care of yourself in the process.
As far as cutting down on smoking is concerned, I have not thought about it yet but let's see. I am quite health-conscious and control my diet. I eat right and work out regularly. I take care of myself as much as I can.