Quick Facts: Overview of the Lungs - MSD Manual Consumer Version (2024)

• Breathing is air going in and out of your lungs

• You get oxygen when you breathe in (inhale) and get rid of carbon dioxide when you breath out (exhale)

All the cells Cells Cells are the basic building blocks of the body. All tissues and organs are made of billions of different cells. Human cells vary in size, but all are quite small. Even the largest, a fertilized... read more in your body need oxygen to turn food into energy. The process of turning food into energy creates waste in the form of carbon dioxide, which must be released from your body.

• Your brain monitors the levels of oxygen, carbon dioxide, and acid in your blood

• These levels determine how fast and deep your brain makes you breathe

• Contraction of your rib and diaphragm muscles expands your chest and pulls air in

• When these muscles relax, your chest gets smaller and you exhale

Problems that involve your brain, like a stroke Stroke A stroke is a sudden brain problem that happens when a blood vessel in your brain either gets blocked or breaks open and bleeds. As with all organs in the body, the brain needs oxygen and nutrients... read more , drug overdose, or extreme alcohol intoxication, can interfere with the part of your brain that controls breathing. These problems can make you breathe too slowly or even stop breathing.

Your airways and lungs can become infected, resulting in bronchitis Acute Bronchitis Your bronchi are the tubes that carry air into your lungs. Bronchitis is when the bronchi become swollen and irritated. Acute bronchitis starts suddenly, usually over a few days. Acute bronchitis... read more , bronchiolitis Bronchiolitis Bronchiolitis is inflammation of the small airways in the lungs in babies and children under 2 years old. The inflammation makes it hard for them to breathe. Bronchiolitis is caused by an infection... read more , or pneumonia Pneumonia Pneumonia is an infection deep in your lungs. The infection involves the small air sacs in your lungs (alveoli). Pneumonia is different from infection of the air passages (bronchi) in your lungs... read more , depending on where the infection is. Pneumonia is infection in the alveoli.

The airways can become narrowed by asthma Asthma Asthma is a condition in which the breathing passages (airways) in your lungs get narrow. When the airways are narrow, it's hard to breathe. Breathing often makes a squeaky sound called wheezing... read more or blocked by a foreign body such as a piece of food.

Blood vessels inside your lungs can be blocked by blood clots, called a pulmonary embolism Pulmonary Embolism (PE) A pulmonary embolism is a clump of material (usually a blood clot) that gets stuck while moving through your bloodstream and blocks a blood vessel in your lungs. A pulmonary embolism blocks... read more .