Further to what Little Hawk said, you have these little microscopic hairy things in your respiratory tract called cillia. The sort of swish the junk up out of your lungs. Smoking destroys them and your body's ability to get that junk out and can result in chronic bronchitis and all the gross stuff associated with it. (coughing up gunk, gurgly lungs.) When you quit smoking, the cillia start growing back and pushing stuff out again. The small nerves in your nose, mouth, throat and lungs start growing back and working again too. Not only do things taste and smell better, but you may feel more irritation than you have for a long time. All of this passes, but it's a sign that you're healing.

Sunflower seeds are great. I think it takes about as much in calories to get the suckers open as they contain. Toothpicks work, sugar free gum if your fillings don't come out, drinking lots of water, occasional deep breathing, walks, playing an instrument are some things I can think of doing instead of smoking.