Eating Fish And High Blood Pressure

Fish oil is one of the most effective natural remedies for high blood pressure. Many trials show that high dose fish oils (above 3g per day) can lower blood pressure, but latest research suggests that lower doses of fish oil, which are easily achieved by eating more fish, are also worthwhile.

Fish oil lowers blood pressure

Over 300 volunteers with high blood pressure were asked to take a fish oil that provided either 0.7g or 1.8g of the long-chain omega-3s (EPA and DHA), or a control oil, during three separate periods of 8 weeks, with a washout period in-between. This showed the effect of each dose of fish oil on each person’s blood pressure readings, compared to the control oil.

In those with systolic hypertension (upper reading greater than 140mmHg), daily doses of 0.7 g EPA+DHA lowered their blood pressure by 5mmHg – enough to reduce the risk of heart attack or stroke by 20%. There were no significant changes in diastolic blood pressure (the lower reading) however.

How does fish oil lower blood pressure?

The long-chain omega-3s, EPA and DHA, are though to increase the production of signalling molecules that have beneficial effects on heart rate, heart work load and arterial dilation. DHA appears to be more important for heart health than EPA. This study, for example, used a fish oil that supplied DHA:EPA in a ratio of 1.4to 1 – roughly the same as is naturally found in marine sourced fish oils.

While DHA and EPA enriched fish oils, and algae extracts, are available in supplement form, you can obtain this lower level of EPA and DHA by eating two or three portions of oily fish per week, such as mackerel, herring, salmon, trout, sardines, pilchards, fresh tuna (not tinned), as shown in the table below.

Type of Fish

Portion size (grams)

DHA + EPA per portion (grams)

Kippers 150g 3.89 g
Salmon 150g 3.25g
Mackerel 150g 2.89g
Pilchards (in tomato sauce) 110g 2.86g
Herring 150g 1.97g
FRESH Tuna 150g 1.95g
Trout 150g 1.73g
Tinned sardines  100g 1.67g
Plaice 150g 0.45g
Cod 150g 0.38g
Haddock 150g 0.24g
TINNED Tuna (in oil, drained) 45g 0.17g
TINNED Tuna (in brine, drained) 45g 0.08g


Other sources of omega-3s (some of which are converted into EPA + DHA in the body) include wild game meat such as venison and buffalo, grass-fed beef and omega-3 enriched eggs.

For more information on how fish oils can lower your blood pressure, visit omega-3 fish oil.

Image credit: foodonwhite/shutterstock

About Dr Sarah Brewer

QUORA EXPERT - TOP WRITER 2018 Dr Sarah Brewer MSc (Nutr Med), MA (Cantab), MB, BChir, RNutr, MBANT, CNHC qualified from Cambridge University with degrees in Natural Sciences, Medicine and Surgery. After working in general practice, she gained a master's degree in nutritional medicine from the University of Surrey. Sarah is a registered Medical Doctor, a registered Nutritionist and a registered Nutritional Therapist. She is an award winning author of over 60 popular self-help books and a columnist for Prima magazine.

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10 thoughts on “Eating Fish And High Blood Pressure

  • Robert

    I really had to read this because I have been taking fish oil for about 10 years now. A few months ago my heart would flutter and make me cough which alarmed me because people on both sides of the family have heart problems so I had a whole bunch of cardio tests done where they use these different machines that look like they come from an episode of Star Trek or something lol. You Doc, would obviously know wayyy more than I on what they were, lol. Anyway, they said everything looked eXcellent and told me that I was just drinking to much coffee, I had to confess . But it did give me confidence in my heart that they found nothing ! If something happens now then so be it, lol. The only thing I do different is get the eccentric coated caps because I went through a whole gigantic bottle of the standard caps and talk about fish burrrps, whew. Thanks for this post and you have a beautiful site Dr Sarah Brewer ; )

  • carl

    Hello Sarah,
    This is a very interesting post and it’s close to my heart.

    For some time |I have been in a position where I am having to re-learn my lifestyle choices due to age, and I have recently come to terms with the need to stop living like I am still 30.

    The changes I have made have been in the amount of veg and the choice of cooking styles, where I am basically eating steamed veg and fish, and possibly some white meat.

    In your view, do you think there is anything to be said for the growing believe that vegetarianism or in fact a vegan diet is worth pursuing in terms of general health?

    many thanks for your help


  • Yvonne

    Hi there,

    I eat salmon 2-3 times a week. It is a must-have fish for me so it’s great to know that it has DHA and EPA. I read in your reply to another comment that “If eating canned tuna, opt for versions canned in olive oil or springwater – not sunflower oil or brine.” How is olive oil or springwater better than tuna canned in sunflower oil or brine?

    • DrSarahBrewer

      Hi Yvonne, brine is no good if you have high blood pressure as it is salt water, and contains sodium Spring water is better as it is plain water with some beneficial minerals. Olive oil is a good source of monounsaturated fats and is an important component of the heart-healthy Mediterranean diet. Sunflower oil is high in omega-6s a type of oil that promotes inflammation and which is widely present in processed foods. Most of us would benefit from cutting back on omega-6s and increasing our omega-3s. Hope that helps – if not drop me another line!

  • Daryl Roberts

    Isn’t fish good for reducing cholesterol levels as well? I seem to remember a Channel 4 documentary with the Van Tulliken twins (both doctors) looking at how a fish diet was responsible for low levels of heart disease and cancer in Inuit communities and, since the introduction of processed foods, they;re now succumbing to the same aging diseases as are prevalent in the Western world.

    • DrSarahBrewer

      FIsh oil has a neutral effect on total cholesterol level but may improve the balance so that the good HDL form goes up and the ‘bad’ LDL-form comes down. The most lprotective effects related to reduced inflammation and the blood thinning effect. Few people following a western style diet eat enough fish to gain full heart protection however, which is why I believe an omega-3 supplement is a good idea.

  • ido barnoam

    As a Tuna lover, Its great to know that Tuna also supplements Omega 3.
    all though its in relatively small quantities, its feels good to know that Tuna is very contributing and healthy.

    How many dishes of Tuna you would recommend a week, based on the table?

    What I’m really interested in is how much is too much? 🙂

    • DrSarahBrewer

      Variety is key. There is some concern about mercury build up in deep sea fish, so you might want to follow the advice for pregnant women which is to limit intakes to no more than 2 tuna steaks a week (170g raw each) or no more than 4 cans of medium-sized cans of tuna a week. I can’t think that anyone would want to eat more than that anyway! If eating canned tuna, opt for versions canned in olive oil or springwater – not sunflower oil or brine. No-drain versions are also available.