What Causes Blood Clots? Smoking Is a Major Factor

You probably know the basics about blood clots and how they endanger your health. But what causes blood clots, and could you be putting your own health at risk?

While many risk factors for blood clots are beyond your control, some are related to your habits, meaning you can take steps toward preventing blood clots. Being overweight or obese, sitting for extended periods of time or living a sedentary lifestyle, for example, can increase your risk of developing certain types of blood clots. You can also lower your risk of blood clots by not smoking.

Why blood clots are dangerous

Blood clots in and of themselves are not dangerous. Clotting is a normal function of the body—when you experience an injury, the body forms a clot to stop the bleeding. Once the wound begins to heal, the blood clot breaks down.

But in some cases, blood clots can form when and where they shouldn’t. Your body might produce too many clots or they may linger in the body rather than breaking down. This can be dangerous, since clots clog up blood vessels and can travel to other parts of the body, creating blockages.

Blood clots can form in the arteries, in what’s known as an arterial clot, and they also affect the veins. Deep vein thrombosis is a common and potentially life-threatening type of clot within a vein, often occurring in the lower body, including the pelvis and legs.

Blood clots can also form in or move into other areas of the body, such as the lungs, brain, heart and kidneys. When this happens, dangerous and even deadly conditions can occur, including heart attack, stroke and kidney failure.

The symptoms of a blood clot depend on where in the body it occurs. A clot in the heart, for example, may cause chest pain, while one in the lungs can lead to shortness of breath. Swelling, tenderness and warmth are all common symptoms of blood clots in the arms or legs.

How smoking affects your blood

Wondering how smoking increases the risk of clots? Blood clots are made up of platelets, proteins and cells in the body that clump together.

When you smoke, your platelets are more likely to stick together. That’s because exposure to the chemicals found in cigarettes changes the surface of the platelets in your blood.

But that’s not the only reason smoking increases the risk of blood clots. Smoking also damages the lining of the walls of the body’s blood vessels, which contributes to blood clot formation.

How much more likely are blood clots among those who smoke? A 2010 study looking at a particular type of blood clot in the veins called venous thromboembolism found that smokers were up to 52% more likely to develop the condition.

Vaping is seen by some as a “safer” way to smoke, but research presented in September 2021 found that e-cigarettes also increase the risk of blood clots. The study reported that the risk of blood clots increased rapidly in the 15 minutes after smoking an e-cigarette.

Smoking is a significant risk factor for blood clots by itself, but the risk increases when smoking is combined with other risk factors. Someone who smokes and is also overweight, or who smokes and has medical conditions associated with blood clots like diabetes or cancer, is at a particularly high risk of developing dangerous clots.

How blood clots are diagnosed

If your doctor suspects you may have a blood clot, imaging tests help confirm a diagnosis and determine the clot’s exact location and size. Ultrasound can find potential blood clots in the arms and legs, while CT scans look for clots in the head, lungs, neck, chest and abdomen.

In many cases, these scans are ordered on an urgent basis, since blood clots can contribute to life-threatening health conditions. In others, though, your doctor may recommend scheduling an appointment for a CT scan or ultrasound as a precautionary measure, such as before or after a surgical procedure.

If you or a loved one require an imaging scan to check for blood clots, American Health Imaging has the technology and expertise you need, with same-day appointments and extended hours. We can step you through the process from start to finish, helping you understand what to expect every step of the way. You’ll receive fast and accurate results you can trust.

CT scans are used to detect and diagnose blood clots before they contribute to a life-threatening health issue such as stroke. Learn more about CT scans and how they work.