Elevated blood pressure, a problem many people have without knowing it, is the major cause of early death. Our lifestyle and what we eat play an enormous role and according to a new meta-analysis that is published in Journal of the American Heart Association, daily intake of three grams of omega-3 fatty acids can reduce your blood pressure. It is possible to get this amount of omega-3 by consuming a serving of oily fish like herring or taking a high-quality fish oil supplement.
Elevated blood pressure occurs when the heart pumps blood through the arteries at higher-than-normal pressure. This can be a result of clogged arteries, and the increased pressure due to reduced blood flow exposes the heart to wear and tear that can eventually cause a thickening and stiffening of the heart muscle. Many people suffer from elevated blood pressure without having any noticeable symptoms. In some cases, problems like headaches, visual disturbances, heart palpitations, breathing difficulty, or nosebleed may occur. Left untreated, elevated blood pressure can lead to stroke or cerebral hemorrhage, coronary infarction, and early death.
It also appears that many people in anti-hypertensive therapy continue to suffer from elevated blood pressure. It is therefore a good idea to have your blood pressure checked every now and then.
Ageing, diet, lifestyle, and waist circumference play a critical role in determining our risk of elevated blood pressure, and we can do a lot as individuals to prevent the problem. Science also points to omega-3 fatty acids as having a positive effect, but only if we consume enough.
Facts about measuring blood pressure
- Blood pressure is measured in mmHg (millimeters of mercury)
- The systolic blood pressure is the pressure caused when the heart contracts and pushes blood into the arteries
- The diastolic blood pressure is the pressure that occurs when the heart relaxes and fills with blood
- Normal systolic/diastolic blood pressure in adults at rest is around 120/80
- Blood pressure automatically goes up with stress to prepare the body for the fight-or-flight reaction
- If the systolic blood pressure is above 140 mmHg and/or the diastolic reading is higher than 90 mmHg, the blood pressure is too high
- It is important to perform several blood pressure measurements after each other to get a reliable picture
Omega-3 fatty acids and their effect
Omega-3 fatty acids are essential, and we have to get them from our diet. Our cell membranes contain two types of omega-3 called EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) that have a host of physiological functions in the body, one of which is to keep cell membranes pliable.
Oily fish are rich in both EPA and DHA, and these two types of omega-3 are easy for the body to utilize. According to the FDA (Food and Drug Administration), adults need around 1.1 – 1.6 grams of omega-3 each day depending on age and gender. Although some studies have shown that omega-3 fatty acids can lower blood pressure, it is not until now that science has been able to pinpoint the amount with the optimal effect, and it seems that it takes more than previously thought to effectively lower blood pressure.
Three grams of fish oil daily delivered the best effect
In the new meta-analysis, which is published in Journal of the American Heart Association, the scientists studied the results of 71 clinical studies that were published in the period between 1987 and 2020. All studies looked at the relation between elevated blood pressure and the intake of EPA and DHA. Around 5,000 people aged 22-86 were included in the studies, some of which had elevated blood pressure and cholesterol levels, while others did not.
The analysis showed the following:
- In participants who consumed 2-3 grams of EPA and DHA daily (from food and/or supplements), systolic and diastolic blood pressure, respectively, was 2 mmHg lower on average than in the participants that did not consume EPA and DHA.
- Participants with elevated blood pressure who got three grams of omega-3 fatty acids daily experienced a 4.5 mmHg drop in systolic blood pressure. Participants without elevated blood pressure had a 2 mmHg drop in systolic blood pressure.
- Participants with elevated blood pressure who got five grams of fish oil (EPA and DHA) daily had a 4 mmHg drop in systolic blood pressure, while those without elevated blood pressure had a 1 mmHg decrease.
- The omega-3 fatty acids had the same positive effect on participants with elevated levels of cholesterol and other blood lipids
As seen in the study, daily intake of three grams of omega-3 fatty acids from food or supplements has the best effect on blood pressure, and people who already have elevated blood pressure levels seem to benefit the most.
How to get three grams of EPA and DHA every day
EPA and DHA are mainly found in oily fish such as tuna, wild salmon, mackerel, herring, and anchovies. Beware that tuna and certain other types of fish contain more heavy metals. It is also important to stress that farmed salmon contains far less EPA and DHA because of the unnatural fodder they get. You can get three grams of omega-3 fatty acids by eating a serving of oily fish like herring or wild salmon or by taking a high-quality fish oil supplement.
More useful tips on foods that help reduce blood pressure
In the following article you can read more about how to lower your blood pressure by reducing your intake of sodium and eating more potassium from fruit and vegetables.
Xin Zhang et al. Omega-3 Polyunsaturated Fatty Acids Intake and Blood Pressure. A Dose-response Meta-Analysis of Randomized Controlled Trials. Journal of the American Heart Association. June 2022
Peer-Reviewed Publication. About 3 grams a day of omega-3 fatty acids may lower blood pressure, more research needed. EurekAlert 1-june-2022
Nikolai Hoffmann-Petersen, Torsten Lauritzen, Jesper Nørgaard Bech og Erling Bjerregaard Pedersen: High Prevalence of Hypertension in Danish Population Telemedical Home Measurement of Blood Pressure in Citizens Aged 55-64 Years in Holstebro County. American Journal of Hypertension. 2015
Houston M.C. The importance of potassium in managing hypertension. Curr. Hypertens. Rep. 2011. PubMed
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