Get Away from the Road
That is, if you live too close to a freeway or major road. One of the strongest toxins in the air—PM2.5—nearly doubles the risk of death stemming from respiratory causes. The biggest factor for PM2.5 other than mites inside your home: traffic density. That's why we recommend that you live at least 100 meters and preferably 300 meters from a major road (300 meters is about the size of three football fields). At the same time, encourage tougher government standards on pollution by writing the EPA, your senator, and your representative. More stringent guidelines for certain pollution (particles in the 2.5 to 10 micron range often produced by coal plants and diesel fuel) provide reasonable goals for most urban environments.
Magnesium—a mineral that relaxes the bronchial tubes—can help with asthma. Take 400 milligrams a day. If you routinely produce mucus from your lungs (you cough it up, rather than mucus coming out when you blow your nose, which is usually from a sinus conditions), consider N-acetyl-cysteine. It's a substance that loosens mucus and boosts production of one of your natural antioxidant scavengers called glutathione, which helps prevent damage in lung tissue. We recommend 500 milligrams twice daily. Even caffeine can help people with asthma. Caffeine seems to stabilize and shrink the lining of the airways and dilate bronchial tubes to help make breathing easier.