Smokers have more wrinkles, and develop heart disease and hardening of the arteries much earlier than nonsmokers. This can lead to loss of limbs from gangrene, and kidney failure because of decreased blood flow. Male impotence is another common consequence of hardening of the arteries. Because they have a lower oxygen concentration in their blood, smokers are more prone to cataracts and lumbar disc degeneration. They have a propensity for poor wound healing, especially after surgery.
Many smokers develop a chronic hacking cough, which can lead to emphysema and bronchitis.
The worst cases become oxygen dependent, hooking them up to an oxygen tank for the rest of their impaired lives. Even young smokers have a decreased exercise tolerance, and perform worse than their nonsmoking counterparts on lung-function testing. I know the cigarette habit is highly addictive and that quitting is difficult, especially when everywhere you go, you see people smoking. But don't be discouraged if you've tried and started up again. For most smokers, it takes seven separate trials before they are finally able to quit.