All other things being equal, which makes your life unhealthier?

Extrapolate a bit: Compare if you smoked three cigarettes a day vs eating three donuts ( assume 1000 calories total) a day.

Eating an extra 1000 calories a day will cause you to put on weight quite rapidly (remember all things being equal – no extra exercising to burn off the extra calories).

Will three cigarettes significantly increase your risk of lung cancer or emphysema?