Smoking is directly responsible for the majority of lung cancer cases (87 percent), emphysema cases, and chronic bronchitis cases.

When you smoke, toxins are carried by your blood to every organ in your body. At the same time, the carbon monoxide in cigarette smoke keeps red blood cells from carrying as much oxygen as normal.

One recent 11-year study found that those with COPD were more likely to develop lung cancer than those without COPD.

Fewer than a quarter of those who attempt to quit are able to make it beyond three months before resuming smoking. Women usually find it harder to quit than do men, even though women have a higher risk of smoking-related diseases. The following suggestions can help you kick the habit, again, for good.

By using nicotine replacement therapy to reduce withdrawal symptoms, smokers who try to quit have a better chance of succeeding.

Secondhand smoke threatens everyone who inhales it, especially kids. Secondhand smoke is not only smoke given off by the burning end of a cigarette, pipe or cigar, but also smoke exhaled by smokers.

“Quitting smoking was just about the toughest thing I’ve ever done,” says S. Epatha Merkerson. “But the struggle was certainly worth it."