COPD: Facts And Myths About The No. 4 Leading Cause Of Death In The U.S.

The sad fact is COPD is the fourth leading cause of death in the U.S. after heart disease, cancer, and stroke. It turns out your lungs are a precious resource -- just like your heart -- and need to be protected throughout your life. Just like heart disease, COPD can be silent for many years, until it's nearly too late. About 24 million Americans have COPD, but half of them don't know it yet. COPD includes emphysema and chronic bronchitis, and it is often a combination of the two. In emphysema, the air sacs in the lungs lose their stretchiness and don't work as well. In chronic bronchitis, irritation and inflammation lead to thick mucus and difficulty breathing. More from Health.com: 3 Ways to Manage COPD The 10 Worst Jobs for Your Lungs 8 Reasons You Can't Stop Coughing

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