Lung health basics

What your lungs do

Every breath carries air down the windpipe into branching airways that end in millions of tiny air sacs. There, oxygen passes into the blood and carbon dioxide passes out. The airways are lined with a thin layer of mucus and tiny hairs that trap dust and germs and sweep them upwards, which is why coughing and clearing your throat are normal protective reflexes.

What can irritate or damage the lungs

• Tobacco smoke, including second-hand smoke, the leading cause of long-term lung disease.
• Air pollution outdoors and indoors, such as traffic fumes, wood smoke, and cooking fumes.
• Dust, chemicals, and fumes at work, for example in construction, farming, or cleaning.
• Respiratory infections such as colds, flu, and pneumonia.
• Allergies and mould, which can trigger airway irritation in some people.

Common signs worth noticing

• Getting out of breath more easily than before, for example on stairs.
• A cough that keeps coming back or brings up mucus most days.
• Wheezing or a tight feeling in the chest.
• Frequent chest infections that take a long time to clear.

When to see a doctor

These signs have many possible causes, and most are manageable once properly diagnosed. A doctor can listen to your chest and arrange simple breathing tests. Seek help promptly for a cough lasting more than three weeks, coughing up blood, unexplained weight loss, or chest pain, and call emergency services for severe breathlessness.

What you can do day to day

The rest of this site focuses on habits that support your lungs alongside medical care: a smoke-free life, cleaner air at home, breathing practice, regular movement, and good nutrition.