Smoking is believed to cause 87 percent of all cases of lung cancer and is a contributing factor in as many as 30 percent of all cancer deaths.
Smoking is a major cause of coronary artery disease and stroke.
It has been linked to an array of other disorders, ranging from slowed wound healing, impotence, infertility, and peptic ulcers to fragile bones in older women. An estimated 430,700 Americans die each year from diseases caused by smoking. Smoking is responsible for an estimated one in five U.S. deaths. Smoking also affects others besides the smoker. Smoking in pregnancy accounts for an estimated 20 to 30 percent of low-birth weight babies, up to 14 percent of preterm deliveries, and some 10 percent of all infant deaths.