Introduction
It is a chronic disease that affects your airways, which are the tubes that carry air in and out of your lungs. Thus in asthma, there is swelling of the tissues in the air passages of the lung, making it tight (bronchoconstriction) thus difficult to breathe.

Causes
There are certain things that can make asthma symptoms worse and lead to asthma attacks. Some of the more common things that can worsen your asthma symptoms are exercise, allergens, irritants, and viral infections. The lists below give some examples of things that can worsen asthma symptoms.
Animal dander (from the skin, hair, or feathers of animals)
Dust mites (contained in house dust)
Cockroaches
Pollen from trees and grass
Mold (indoor and outdoor)
Cigarette smoke
Air pollution
Cold air or changes in weather
Strong odors from painting or cooking
Scented products
Strong emotional expression (including crying or laughing hard), and stress

Symptoms
Breathing gets pretty difficult, Episodes of wheezy difficulty in breathing, Narrowing of the air passages in the lungs and hence increased resistance to airflow., Rapid and considerable changes in airway obstruction, Frequent nocturnal episodes and low morning peak flow values, Symptom-free periods, Bronchial hyper-responsiveness to nonspecific stimuli such as cold air or histamine, which generally varies within short periods of time, and is sometimes reversible, either spontaneously or with treatment.

Remedy and prevention
EAT plenty of Foods rich in the B vitamins such as green leafy vegetables and pulses.
Eat plenty of Good sources of magnesium such as sunflower seeds and dried figs.
Learn about your asthma and how to control it.
Use medications as directed by your doctor to prevent or stop attacks.
Avoid things that make your asthma worse, as much as possible.
Get regular checkups from your doctor.
Follow your asthma action plan.
Babies exposed to tobacco smoke are more likely to get asthma. If a mother smokes during
pregnancy, her baby may also be more likely to get asthma.
Personal smoking may also cause asthma.

Obesity may be linked to asthma as well as other health problems.