A new report by the U.S. Surgeon-General says that smoking causes immediate damage to a person's lungs and DNA. It says even inhaling very small amounts of second hand smoke is harmful.

Tobacco companies come in for heavy criticism, accused of engineering cigarettes to be addictive, and portraying new products as safer.

The report says quitting smoking can reverse a great deal of the damage over time. Cigarettes kill 443-thousand people every year in the US, causing cancer, heart disease, lung disease and other illnesses.

Dr. Regina Benjamin, U.S. Surgeon General, said, "The chemicals in the tobacco smoke damages the delicate lining of your lungs and can cause permanent damage, and that reduced your lung's ability to exchange air efficiently. And that's what causes the COP, or the chronic obstructive lung disease, which includes emphysema."