i was a smoker for 35 started age of 12 now i am 47 ,i noticed within 14 days of quitting the quality life coming back and smells of food and outdoor smells quickly returned,but my addiction to it was not nicotine. it was the habit .the motions of the hand and mental parts of it ,i got on Chantix and it really worked for me made cigs taste like crap the first day i used it 5 days later i was done the smell and the taste really was gross. so it made it so easy to turn the smoking habit off.and yes the lungs do repair them selfs but any damage done such as scaring etc will never go away.so to quit before that happens. it`s a big plus in making a 100% recovery.its never to late to quit!!!