What’s The Difference: Arteries, Veins, and Capillaries?

The network of blood vessels in your body is over 60,000 miles long, and it is made up of three different types of blood vessels: arteries, veins, and capillaries. Each of these blood vessels is crucial for the movement of blood throughout your body.

What’s the Difference: Arteries, Veins, Capillaries?

How can you tell if a blood vessel is an artery, vein, or capillary? Blood vessels are tiny tube-like structures that transport blood inside your body. You can differentiate the three based on a few traits.

What are Arteries?

Arteries are the largest type of blood vessels in your body, carrying oxygenated blood away from your heart. They have thick walls and a muscular layer that keeps your blood flowing.

The largest artery in your body, the aorta, transports blood from your heart to your organs. Both arteries and arterioles alter in size to maintain a healthy blood pressure level in your body.

Arteries have the following characteristics:

With the exception of pulmonary blood vessels, arteries carry oxygenated blood away from the heart and veins carry deoxygenated blood toward the heart. In contrast to the arteries, veins have thinner walls and need valves to keep your blood flowing.

Arteries are only found deep inside your muscles, while capillaries are found inside tissues throughout your body.

What are Veins?

Because veins lack a muscle layer like arteries do, they must rely on valves to keep your blood flowing. Veins begin as small blood vessels called venules, which get larger as they approach your heart. Veins transport deoxygenated blood towards your heart and are frequently found near your skin.

Vein traits:

• Compressible, unlike arteries
• Less muscle and elastic tissue
• Have wide lumen
• Have narrow walls
• Include valves that maintain blood flow
• Usually low pressure

The walls of a vein are thinner than those of an artery. Veins carry blood from your organs and towards your heart, while arteries carry blood away from your heart. Veins are closer to the surface of your body than arteries are deep inside your muscles.

The difference between a vein and a capillary is that veins have thicker walls than capillaries, but capillaries lack valves and disperse blood and nutrients between veins and arteries.

What are Capillaries?

Capillaries, the smallest form of the blood vessel, connect your arteries to your veins. They can be as small as 5 micrometers, or less than a third of the width of a hair.

Endothelial cells make up a capillary wall, which is only one cell thick and permits oxygen, nutrients, and waste to move to and from tissue cells.

Capillary properties:

• Are found inside every tissue
• Possess a thin wall
• Transport blood between arteries and veins
• Transport blood that is both oxygenated and deoxygenated
• Have no muscular tissue
• Have no valves

Compared to arteries, which are big and muscular blood vessels found deep inside your muscles, capillaries are relatively small blood vessels distributed throughout your body.

Both capillaries and veins can occasionally be seen through the skin. But veins are bigger and thicker than capillaries. Whereas most veins only carry deoxygenated blood, capillaries can also carry oxygenated blood.

How Can I Maintain Healthy Blood Vessels?

Keep your blood vessels robust with healthy lifestyle choices, since these can help prevent blood vessel problems like high blood pressure and blood clots.

Here’s what you can do:

• Keep your weight in a healthy range
• Avoid smoking
• Limit your alcohol consumption
• Follow a diet reduced in saturated fat, salt, and cholesterol
• Monitor your blood pressure
• Maintain healthy cholesterol levels
• Engage in regular exercise

Your arteries, veins, and capillaries serve as an essential road map for the movement of your blood. Consult your doctor on how to improve or maintain good heart health. 

Learn more about Heart Health here.