Smoking over a long period of time can cause many health problems, not the least of which is a coarsening of the facial skin. Premature wrinkles have been noted in those who smoke heavily, and since smoking causes a loss of circulation, the facial coloring may look pale or jaundiced. Because cigarette smoke increases the amount of carbon dioxide in the blood, the result is dry and dull-looking skin. Loss of circulation may also cause hair loss, since a healthy blood supply to the scalp helps keep the hair follicles healthy. Smoking also can cause discoloration of the teeth, and cracking of the lips from constant exposure to cured paper on cigarettes. Smoking may also turn the fingers yellow on a permanent basis, and cause yellowing of the fingernails.