"Drinking water before and during a meal helps keep you hydrated and can make you feel full on fewer calories. Drinking water satisfies the craving for having something to put in your mouth instead of a cigarette. One recent study showed that sipping cold water through a straw triggers the release of dopamine, a feel-good hormone in the brain that may counteract stress."

http://www.webmd.com/smoking-cessation/quit-smoking-10/avoid-weight-gain?ecd=wnl_lbt_122210&v=PFX&p=UNK