Your two lungs make oxygen available to your body and remove gases like carbon dioxide. There are many conditions that can affect your lungs. Not smoking may help you prevent some illnesses.


A step-by-step explanation of how your lungs work.

What are your lungs?

Your lungs make up a large part of your respiratory system, which is the network of organs and tissues that allow you to breathe.

You have two lungs, one on each side of your chest, which is also called the thorax. Your thorax is the area of your body between your neck and your abdomen.

Right lung

The lung on your right side is divided into three lobes: the superior, the middle and the inferior. It’s shorter than your left lung, but also wider than your left lung. Both of your lungs are covered with a protective covering called pleural tissue.

Left lung

Your left lung has two lobes: the superior and the interior. Your left lung is smaller than the right because your heart is where the middle lobe on your left lung would be. Your left lung has two parts that your right lung doesn’t have: the cardiac notch (where your heart fits) and the lingula, an extension of the superior lobe.


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What do lungs do?

Your lungs make oxygen available to your body and remove other gases, such as carbon dioxide, from your body. This process takes place 12 to 20 times per minute.

When you inhale through your nose or mouth, air travels down your pharynx (back of your throat), passes through your larynx (voice box) and into your trachea (windpipe).

Your trachea is divided into two air passages called bronchial tubes. One bronchial tube leads to your left lung, the other to your right lung. For your lungs to perform their best, your airways need to be open when you inhale and when you exhale. They also need to be free from inflammation (swelling) and abnormal amounts of mucus.

Your bronchial tubes lead to smaller air passages called bronchi, and then into bronchioles. The bronchioles end in tiny air sacs called alveoli, where oxygen is transferred from the inhaled air to your blood. Alveoli look like clusters of small round fruits.

After absorbing oxygen, the blood leaves your lungs and is carried to your heart. From there, it’s pumped through your body to provide oxygen to the cells of your tissues and organs.

When cells use oxygen, they produce carbon dioxide and transfer it to your blood. Your bloodstream carries the carbon dioxide back to your lungs. When you exhale, you remove the carbon dioxide.

Your respiratory system prevents harmful substances from entering your lungs by using:

  • Small hairs in your nose that act as an air-cleaning system and help filter out large particles.
  • Mucus produced in your trachea and bronchial tubes to keep air passages moist and help catch dust, bacteria and other substances.
  • The sweeping motion of cilia (small hairs in your respiratory tract) to keep air passages clean. One of the reasons that cigarette smoke is dangerous is that it stops cilia from working properly.

Interesting facts about your lungs

  • You can have lobes of your lung removed and live. You can even live with only one lung.
  • Lungs are the only organs in your body that will float.
  • Exercise can help you increase your lung capacity.
  • A typical adult has 300 million to 500 million alveoli.


Where are your lungs located?

Your lungs are located in your chest (your thorax). Your thoracic cavity is the name of the space that contains your lungs and other organs. Your lungs rest on a muscle called your diaphragm.


What do lungs look like?

Healthy lungs are pinkish-gray in color. You’ve probably seen photographs that compare the lungs of people who smoke to the lungs of people who don’t. Damaged lungs are darker gray and can have black spots in them.

Your triangularly shaped right and left lungs look a little bit like the ears of an elephant.

A typical lung in a human adult lung weighs about 2.2 pounds and is a little longer than 9 inches when you’re breathing normally, and about 10.5 inches when your lungs are completely expanded.

Conditions and Disorders

What are the common conditions and disorders that affect your lungs?

There are many different lung conditions. Some are minor and temporary, while others are chronic and more severe.

  • Asbestosis: Inhaling asbestos fibers causes scars on your lungs and pleural tissue.
  • Asthma: Airway tightening makes breathing difficult.
  • Bronchiectasis: Inflamed bronchi cause you to cough up mucus and have trouble breathing.
  • Bronchitis: The main characteristic of this condition is coughing. Bronchitis can be acute or chronic.
  • Chronic obstructive pulmonary disease (COPD): This is a progressive breathing disorder that can’t be reversed.
  • COVID-19: This infection can cause mild or severe respiratory illness.
  • Croup: This respiratory infection happens in children under the age of 5.
  • Cystic fibrosis: This inherited condition causes sticky mucus to build up in your lungs and other organs.
  • Influenza: This lung disease, known as the flu, is caused by a virus.
  • Lung cancer: A major risk factor for developing lung cancer is smoking cigarettes.
  • Mesothelioma: This type of cancer is mainly caused by breathing in asbestos fibers.
  • Pneumonia: This lung infection causes fluid in your lungs and can lead to hospitalization.
  • Pulmonary fibrosis: Scarring of your lungs causes breathing difficulty. It isn’t curable.
  • Pulmonary nodules: These growths in your lungs are mainly benign (noncancerous).
  • Respiratory syncytial virus (RSV): This respiratory infection can happen in children and adults.
  • Tuberculosis: This infection affects your lungs, but can also affect other body parts.


What are some common signs or symptoms of lung conditions?

Common signs and symptoms of lung conditions include:

What are some common tests to check the health of your lungs?

Your healthcare provider can tell certain things during a physical examination. They can:

  • Listen for sounds in your lungs, including those that indicate a problem, including crackles (also called rales), wheezing and stridor (a high-pitched noise).
  • Count the number of breaths you take (your respirations).
  • Hear a change in your voice while they’re listening to your lungs.
  • Use a device called a pulse oximeter to measure the oxygen levels in your blood.

In addition to a physical examination, your provider may order different kinds of tests, including:

Imaging tests show your provider what your lungs look like

Lung function tests (also called pulmonary function tests) tell your provider how well your lungs are working

Procedures that may require sedatives or anesthesia

  • Bronchoscopy or endobronchial ultrasound bronchoscopy (EBUS).
  • Lung biopsy.
  • Thoractomy. Your surgeon makes a cut in between your ribs so they can diagnose or treat body parts located in your chest.

What are common treatments for lung conditions?

If you have a lung condition, your treatment will depend on your actual condition, as well as your health status. Types of treatments may include medications, exercises, devices and surgeries.

Medications may be offered as inhalers, nebulizer solutions, oral products or injections (shots)

  • Steroids to reduce inflammation (swelling) in airways.
  • Antibiotics to treat infections.
  • Bronchodilators to open up airways. These come in long-acting and short-acting versions.
  • Mucolytics to make mucus thinner so it’s easier to cough up and out.
  • Oxygen therapy to improve your oxygen levels.
  • Chemotherapy and/or radiation to treat cancers.
  • Vaccines to help prevent infections.

Exercises and devices


  • Lobectomy, the removal of one lobe of the lung.
  • Bilobectomy, the removal of two lobes of the lung.
  • Removal of sections of lungs.
  • Thoracentesis, a procedure to drain fluid from your lungs.
  • Thoracotomy.
  • Pneumonectomy, the removal of one lung.
  • Lung transplant.


What can I do to keep my lungs healthy?

There are many things you can do to keep your lungs healthy or to help manage lung conditions.

  1. The first thing you can do is to stop smoking and vaping.
  2. Try to reach and maintain a healthy weight. People with obesity have less space for lung expansion.
  3. Exercise regularly. Check with your provider before you start exercising.
  4. Eat healthy foods in moderation.
  5. Stay hydrated, unless your provider gives you a limit on how much liquid you can drink.
  6. Get the vaccines that your provider suggests.
  7. Wash your hands well to avoid infections.
  8. Limit your exposure to people who are sick.

A note from Cleveland Clinic

Even though your respiratory system has ways to protect the body, your lungs can still get sick. Some conditions aren’t serious and are over quickly. Other conditions are more serious and long-lasting. If you have a chronic lung illness, your regular healthcare provider may refer you to a pulmonologist. It’s important to follow the suggestions from your healthcare team so you can breathe easily.

Medically Reviewed

Last reviewed on 08/15/2022.

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