Essentially everyone smokes in Istanbul. Women, men, kids (well, not really kids) all seem to be always smoking. Technically smoking isn't allowed inside (everyone posts a no smoking sign), but because of a recent crackdown on outdoor tables at bars and restaurants, you'll find yourself coming home smelling like a cigarette after going out. To escape from the smoke, try avoiding the cheapest bars and nightclubs, and look for places (for instance in Asmalimescit) that are have a lot of fresh air and open windows.