Nicotine is an appetite suppressant. Give it up, and your appetite comes back, as well as you replacing the hand-to-mouth action of smoking with the habit of snacking, so it's like a double whammy as far as weight gain goes. Keep a food diary if you can, try to avoid chewing gum (the artificial sweeteners in it trigger more sugar cravings, it's just replacing one dirty habit with another, lol!), try to replace your old 5-min ciggie breaks with exercise breaks. I have a treadmill in my lounge room and found it really helpful to just jump on there for 5-10 mins at a time when I was craving a cigarette... of course I'm back on the evil things now so my weight's dropped again, but hang in there You're strong enough to kick an addiction worse than heroin, you're certainly strong enough to kick that extra weight! Good luck