What is asthma?

For nearly 31 million Americans, asthma causes debilitating and potentially life-threatening breathing complications

The number of people diagnosed with asthma has been on the rise for decades, making it one of the most widespread health threats in the nation. And no one has yet found a cure.

About a third of asthma sufferers are children. In many ways, they are the most severely affected by the disease. Asthma is the number-one cause of missed school days in the country. Children are also far more likely than adults to be hospitalized for the disease and twice as likely to die from it. And contrary to popular belief, most children do not grow out of the disease as adults.

Most asthma attacks are triggered by an immune system run amok. Rather than ignoring the particles of pollen and pet dander, mold, tobacco smoke, and auto exhaust that float into the lungs with every breath, the airways of asthmatics become inflamed. The effect is like breathing through a straw.

Instead of healing, inflammation merely stiffens the airways with scar tissue, and the severity of attacks worsens with every episode. To halt this vicious cycle, it’s best to prevent asthma attacks from happening in the first place by noticing early warning signs such as coughing or faster-than-usual breathing.

No one is certain what causes asthma, but scientists do have some ideas. One of the latest theories, says John Koostra, a Monterey pulmonary doctor and medical director of Community Hospital’s Respiratory Therapy and Pulmonary Wellness programs, is also the most controversial. “The idea is that kids these days are exposed to less dirt and live such clean lives that their immune systems are hyperresponsive to so many things when they’re older,” Koostra says. Known in some circles as the “dirt hypothesis,” this explanation remains controversial.

Koostra thinks worsening air pollution is a far more likely culprit. “More people are living in urban areas where there is a lot of pollution. That increases the risk of pulmonary problems,” Koostra says. And studies have shown that inner-city kids are twice as likely as their suburban and urban relatives to develop asthma.

Indoor air pollution may also play a role in the rising epidemic of asthma. Studies suggest that people are spending longer hours inside more tightly insulated, energy-efficient houses. Irritating fumes from carpets, gas stoves, perfumes, and wood fires get trapped and concentrated.

And because asthma often is an allergic reaction, certain foods can irritate the airways as well. Peanuts, eggs, chocolate, wheat, strawberries, pineapples, and dried fruit are some of the most common food allergies.

But of all the asthma irritants, tobacco smoke may be the most deadly. Children exposed to tobacco in the womb are born with smaller airways, which can put them at greater risk of having asthma.

The best ways to stay healthy are to understand your medications, avoid things that trigger the asthma, and develop and maintain a good rapport with your doctors.