Blood Circulation: How It Affects Your Health

Your circulatory system is what keeps your organs and tissues healthy and functioning. But what exactly is it, and what happens if it gets damaged?

“Your entire health is intimately related to circulation,” says Anahita Dua, MD, a Mass General Brigham vascular surgeon. “Disruption of circulation — whether it’s a problem with the heart unable to push blood, or within the blood vessel that doesn't allow blood to move — all has a serious impact.”

Dr. Dua cares for patients at Massachusetts General Hospital. Here, she explains how circulation works and how it’s important for understanding how to protect your health.

What is blood circulation?

Your circulatory system consists of your heart and all the blood vessels throughout your body.

As the heart pumps, blood pushes out into arteries. These strong, smooth blood vessels carry blood at high pressure to all parts of your body. They branch out to all the different parts of your body, thinning as they go. The smallest arteries are in your feet, the furthest distance from your heart.

After blood delivers nutrients and oxygen to organs and tissues, it travels back to the heart through veins. These are thinner and weaker than arteries since the blood pressure is much lower.

Causes of poor circulation

Certain medical conditions and lifestyle choices can interfere with this process by causing atherosclerosis, fatty deposits (plaques) that stick to the arterial walls and interfere with blood flow. Common causes of atherosclerosis include:

• Diabetes: High blood sugar (glucose) levels can damage blood vessels.
• High blood pressure (hypertension): Higher pressure on your artery walls can damage them.
• High cholesterol: High levels of cholesterol cause fatty buildup (plaque) along artery walls.
• Obesity: Excess weight can strain your heart by making it work harder. Fat can also build up in arteries, resulting in high blood pressure or high cholesterol.
• Smoking: The chemicals in tobacco products damage blood vessels.
• Diet: Eating foods high in fat can increase cholesterol levels. In addition, foods with a high salt content can cause your body to retain water, which results in higher blood pressure.

Some disorders can interfere with blood flow. For instance, Raynaud’s syndrome causes spasms in small blood vessels, causing them to contract and limit blood flow.

How poor circulation affects your health

The impact of poor circulation depends on which part of the circulatory system is affected.

When blood flow is restricted in the arteries, oxygen-rich blood struggles to get to tissues and organs. “What that primary major impact is, is that whatever the end organ was of that blood pathway, it does not get the oxygen and nutrition that it needs to function,” says Dr. Dua. Depriving tissues of oxygen can quickly become an emergency, she adds, because there is a limited amount of time before damage occurs.

Damage to veins often has a slower, less serious impact. Weakened veins struggle to transport blood back to the heart, sometimes forming clots that can lead to complications.

Conditions caused by poor blood circulation

The effects of poor circulation can be felt throughout your body. Early warning signs include pain, cold fingers or toes, or numbness. If left untreated, serious conditions can arise, such as:

• Chronic venous insufficiency (CVI): Severe blood pooling in the veins causes swelling, skin changes, and pain
• Deep vein thrombosis (DVT): Blood clots that partially or completely block blood flow, causing pain or swelling
• Ischemia: A lack of blood supply that can cause organs and tissues to die
• Peripheral artery disease (PAD): The narrowing of the artery that delivers blood to the legs or arms, causing pain with movement
• Varicose veins: Weakened veins that stretch and bulge, resulting in blood backing up or pooling

In some cases, a blood clot can break free. If it becomes lodged in the lungs (pulmonary embolism), heart (heart attack), or brain (stroke), it can completely block blood flow. This is an emergency that requires immediate attention.

If you experience symptoms of poor circulation or have conditions that put you at risk, talk with your doctor. They can recommend lifestyle changes, medications, or surgical procedures to improve blood flow.