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Fish and fish oil reduces the risk of blood clots

There are good and solid evidence for the health benefits of omega-3 fatty acids. More recently, a new scientific study from Norway published in the Journal of Nutrition shows that supplementation with fish oil either equals or was better than eating fish regarding a reduction of venous thrombosis. The combination of fish and fish oil supplements can reduce the risk of venous thrombosis by almost 50%.

The new study included about 23,500 people aged 25-97 years. Data from a previous study called Tromso 4 were used. The series of Tromsø studies were initiated in 1974 in an attempt to do something about the high mortality from cardiovascular disease in Norway.

Significant improvement with fish oil

The new Tromso study showed that a high intake of fish was associated with a slightly reduced risk of developing a venous blood clot (thromboembolism). The study participants who ate fish at least three times a week had a 22% lower risk of developing a venous thrombosis compared with those who ate fish 1-2 times a week. By supplementing with fish oil preparations, the reduced risk became more significant. Study participants who ate fish at least three times a week and additionally supplemented with a fish oil preparation, achieved a 48% reduced risk compared to those who ate fish 1-2 times a week and did not supplement with fish oil.

You have to eat 150 grams (5,3 oz) of fish to correspond to a portion. Fish and fish oil have their content of omega-3 fatty acids in common.

The mechanism by which the intake of omega-3 polyunsaturated fatty acids protect against venous thrombosis is not fully understood. Previous studies of omega-3 fatty acids indicates that they prevent cardiovascular disease due to their capacity to counteract cardiac arrhythmia, platelet clumping and lowering the content of fat in the form of triglycerides in the blood.

About venous thromboembolism

Blood clots are formed as a response to an injury to a blood vessel to prevent bleeding. Venous thromboembolism (VTE) is a blood clot in a vein, which totally or partially obstruct the blood flow. It can also be a blood clot that becomes detached, is transported around the body and finally clogs a blood vessel. These types of blood clots do not always cause symptoms, but some of them can be fatal.


Hansen-Krone IJ, et al. High Fish plus Fish Oil Intake Is Associated with Slightly Reduced Risk of Venous Thromboembolism: The Tromso Study. J Nutr 2014;144: 861-67.

Fish oil supplements - as effective as fresh fish

Scientific studies*) indicates that fish oil provides the same health benefits as eating fish every day. If you want to be sure to get a product with the highest concentration of omega-3 and the best bioavailability, choose a product with:

  • content of EPA and DHA of 70%
  • The fatty acids are easily absorbable free fatty acids
  • Added B vitamin that lowers blood levels of harmful homocysteine

*) Agren JJ, et al. Fish diet, fish oil and docosahexaenoic acid rich oil lower fasting and postprandial plasma lipid levels. Eur J Clin Nutr. 1996;50:765-71.


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