We hear a lot about the risks of lung cancer — but less about a lung condition that’s just as common and debilitating, called COPD. This term, which stands for chronic obstructive pulmonary disease, refers to a combination of two conditions, emphysema and chronic obstructive bronchitis, both of which are caused by lung damage from smoking or exposure to other lung irritants, such as asbestos. Whether you’re a smoker, a former smoker, or just unlucky, you can develop COPD as a result of damage to your lungs that gradually limits their ability to take in oxygen.

When your lungs aren’t functioning at full capacity, symptoms begin to appear that are sometimes so subtle that you may not recognize them as such. And because COPD is a progressive disease that can’t be slowed without treatment — and because it’s the fourth leading cause of death in the U.S. — it’s critical to catch it as soon as possible. Here, seven signs that your lungs are trying to tell you they’re in trouble.

1. Shortness of breath

“Many people start to experience shortness of breath, and they just think "I'm old, I’m out of shape,’ and they don’t do anything about it other than cutting back their activity level,” says Byron Thomashow, a physician and professor at Columbia University Medical Center and chairman of the board of the COPD Foundation. “Then when you have shortness of breath just getting to the bathroom, all of a sudden you take notice.”

The problem with this, Thomashow says, is that the lung damage that constitutes COPD can’t be reversed; all you can do is halt or slow the progression of the disease. And if you don’t start treating it until you’re already out of breath just walking around the house, you’ve got a lot less to work with. Not only that, but cutting back is the last thing you want to do to prevent COPD progression; maintaining and even increasing your activity level is key to keeping the lung function that you have.

One thing to look for: When you’re climbing steps or exercising, do you have trouble inhaling a deep breath? An even more telltale sign: Do you take the elevator instead of the stairs to avoid this feeling? Experiment with different activities to see if you have shortness of breath when you increase your level of exertion, and note if there have been any changes over time. “I ask people, how’s your breathing compared to last year — can you do what you used to do a year ago?” says Thomashow. If you feel your ability to draw a deep breath is declining, ask your doctor to perform lung function tests to give you a clear picture of your lung health.

2. Frequent or worsening coughs

Everyone gets a cough once in awhile, but if you seem to be getting them more frequently, or they linger for a long time or become chronic, it’s time to talk to your doctor. COPD inflames the bronchial tubes and the tiny sacs called alveoli that line the lungs, making them less flexible and elastic. When that happens, the walls of the airways thicken and produce more mucus than usual, which clogs them up.

What you’ll notice is a phlegmy cough that feels like the type that usually accompanies the flu — except you don’t have other flu symptoms. If you cough up mucus that’s any other color than clear, that can be a sign your condition is worsening, says Byron Thomashow of Columbia and the COPD Foundation. The mucus may be yellow, green, or even have blood in it.

One interesting fact to be aware of: If you’re still smoking, your sputum production may not increase despite advancing COPD, whereas sputum production tends to increase after you quit.

Continue to Care2.com to read more warning signs of COPD.

Report a Typo