Lifestyle-related Thrombosis Risks

Thrombosis is a condition which causes excessive blood clotting in the body. Whilst blood clots serve to protect damaged areas of the body and promote improved healing, excessive clotting can put the body at risk.

Clots that form unnecessarily within blood vessels can block or limit the blood flow. In some cases, these clots can break free and travel to different areas of the body. This can have serious health consequences, including; heart attack, stroke and even death.

What causes Thrombosis?

There are many different things that can increase the risk of thrombosis. Although some of these are genetic factors that raise the thrombosis risk, many people also increase their personal clotting risk due to the lifestyle choices that they make. The following lifestyle choices can increase the risk of developing thrombosis or they can worsen existing thromboses.


Smoking can reduce the levels of oxygen in your blood and affect the blood chemistry. Smoking over a longer period of time irritates the cells that line the blood vessels. This irritation can cause the blood vessels walls to thicken over time, which leads to a narrowing of the vessels themselves. This reduces the amount of blood which can pass through at any given moment. It also means that a smaller clot is more likely to cause a total vessel blockage.

Smoking can cause the platelets in the blood to stick together more easily, and then become caught in the thick plaque that builds up in the narrow passages. This means that any clots will become worse very quickly. Stopping smoking will help to reduce the risks down towards standard levels. Although it is impossible to reverse the damage completely, any smoke-free periods will start to make a real difference.


Being overweight significantly increases the risk of developing a deep vein thrombosis (DVT), especially in people who are classified as being clinically obese. Although doctors are unsure about the exact medical reasons for this, there are some credible theories. In general, obese people move far less than those who maintain a healthy weight. Inactivity can result in a slower blood flow, especially in the extremities. This makes unnecessary clotting far more likely in the lower limbs. Extra fat around the waist also constricts blood flow in some blood vessels, which increases the clotting risk in the deep veins.

Other factors that link obesity and thrombosis include obesity-related medical conditions, such as diabetes, which is also known to significantly increase a person’s risk of developing DVT. Losing weight using healthy weight loss measures can help to reduce the risk of thrombosis in most people. However, if a person has already suffered from one deep vein thrombosis, losing weight is not believed to help people to reduce their risk of developing a secondary thrombosis.


Dehydration also increases clotting risks. When the blood does not contain enough fluids, it is more likely to form into harmful clots. The risks are further exacerbated by a narrowing of the blood vessels that occurs when the body needs water. Drinking enough fluid every day helps to keep the blood moving properly through the circulatory system. People must remember to increase the amount of water that they drink on hot days and when they are exercising, because this increases natural fluid loss.

Although a small amount of alcohol is actually thought to have a positive impact on the thrombosis risk, drinkers must be mindful that alcohol-induced hangovers result in the body becoming very dehydrated.


People who lead a sedentary lifestyle put themselves at risk of developing DVT. Although the primary lifestyle cause is a lack of daily exercise, inactivity-induced DVT is also something that affects long-haul air travellers. Those who are immobile because of medical reasons or surgery must also be mindful of their increased thrombosis risk

When a person is inactive for a long period of time, their blood begins to move more slowly. It can start to collect in the extremities, in particular the lower legs. The slowness of the blood flow increases the risk that a clot will start to form. Sufferers are likely to notice gradual swelling in their lower legs. Simple exercises can help to get the blood flowing again. Leg raises and ankle rolls are some of the most basic exercises which can encourage the blood to move around the legs more quickly. It is a good idea to stand up regularly whilst on long haul flights and move around the plane for a short period. Most airlines now provide a short advice leaflet detailing advice that fliers can follow to help to reduce their risk of developing DVT. Those who are forced to spend long periods of time in bed may be given physiotherapy to prevent muscle wastage and reduce the risk of blood clots due to slow blood flow.