In the modern world of cigarettes, automobiles, and heavy industry, it seems hardly surprising that people face increasing rates of lung diseases. However, it’s surprisingly difficult to nail down the cause of asthma—a chronic condition that causes sudden, unexpected narrowing in the airways of the lungs.
Contrary to what you might think, asthma isn’t caused by toxins in the air, but from your body’s overactive response—often, to otherwise minor irritants like dust, mold, and animal dander. During a severe asthma flare-up, the muscle tissue that lines the airways in your lungs can become so swollen that it chokes off your air supply.
The mystery of asthma is why it’s so common in the rich, industrialized countries of the Western world. The reason remains elusive. Some suggest that it’s a side effect of modern living in tightly closed spaces (and, by extension, the build-up of indoor air pollutants). Other researchers support the hygiene hypothesis, which argues that our clean living habits limit our exposure to infection and allergens early in life. Current research is contradictory—some studies suggest that early exposure to allergens can trigger lifelong asthma, while others point to lower asthma rates in environments filled with germs and irritants (daycare centers, families with many children, crowded living spaces, and so on).
Whatever the case, if you experience symptoms of asthma, such as occasional trouble breathing or a nagging shortness of breath, head to your doctor for a lung-function test. Even if your asthma isn’t severe enough to cut off your oxygen supply, the prolonged inflammation can gradually damage your lungs if you don’t manage your asthma with medication. (And no, asthma inhalers cannot cause obesity, even if they contain steroids.
They act directly on the lungs to expand air passageways or reduce inflammation.)
If you have asthma, you may be able to reduce your symptoms by controlling house dust and indoor air pollutants. The key is to identify your personal asthma triggers and work to reduce them.
Source of Information : Oreilly - Your Body Missing Manual