Capillaries are delicate blood vessels that deliver blood, nutrients and oxygen to cells throughout the body. They work in different ways to support organs and system functioning.
Capillaries are delicate blood vessels that exist throughout your body. They transport blood, nutrients and oxygen to cells in your organs and body systems. Capillaries are the smallest blood vessels in your vascular system.
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Capillaries complete the circulatory system by connecting arteries to veins:
Read more about how blood flows through the body.
Capillaries also support a variety of organs and systems. They support the:
Most capillaries are only about 8 to 10 micrometers in diameter (a micrometer is 0.001 mm). They’re so tiny that red blood cells have to pass through in a single file line.
Capillaries contain two layers of cells:
Capillaries have three different shapes, which help them carry out various functions:
Broken capillaries are common. They can occur with severe coughing or vomiting. This causes little red dots on your skin that often heal on their own.
Other conditions affecting the capillaries include:
You can take care of your capillaries by maximizing your vascular health.
You should also work with your healthcare provider to manage conditions that can affect vascular health.
When should I call a doctor about my capillaries?
It may not be necessary to contact your healthcare provider about capillary disease. They may detect problems before you experience symptoms. This makes it possible to start treatments to prevent them from getting worse. It is especially true if you stay current with preventive care, such as annual physical exams.
Contact your healthcare provider if you experience signs of vascular disease. These include:
A note from Cleveland Clinic
Capillaries are delicate blood vessels that deliver blood, nutrients and oxygen to cells. It can be challenging to detect the early signs of capillary issues. Staying current with preventive care and chronic condition treatments can lower your risk.
Last reviewed by a Cleveland Clinic medical professional on 10/05/2021.
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