How dangerous is smoking?

It depends: Depends on a number of variables: what? How much? How long? And of course it is more dangerous for patients with lung disease or a strong family hx. Of emphesema, lung cancer, etc. It is always a good "bet" to stop smoking but some patients will likely live longer if they continue with nicotine for the rest of their lives.

Very: No amount of smoking anything is healthy, period. Too much or too little doesn't make a difference. There is no health reason to smoke.

Very dangerous.: There's nothing good about cigarette smoking. There are about 42 carcinogens in cigarettes,,along with various toxins. Cancer, heart disease, lung disease. Very bad habit to pick up.