smoke ranger this is good info and ur dad being a doc.It has been found not to cause lung cancer though.This is a recent release of this finding.What I respect is being told the truth,good and bad about weed.Yeh,I get a little dingy when smoking.So if a body is going to drink a "cocktail" to "wind down".then what's the deal w/smokin a reefer to "wind down".Personally I would rather have my kids smokin weed then drinking booze,driving around and hiding what they r doing.About the smoke in the lungs,well pnenomia left my lungs scarred from age 3. Also you can overdo anything,all things in moderation.