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Should You Really Be Taking Fish Oil?


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Fish oil might not be the cure-all it’s often advertised to be, and in some cases, it may even cause problems.

is fish oil bad for you?
Is there any real value in taking fish oil? DmitriyDanilchenko/iStock/Thinkstock

Note: This article was originally published in June 2015 and was updated in January 2017 to include the latest research. My original recommendations still stand, and the case for high-dose fish oil supplementation has become even weaker.  

Fish oil supplements continue to gain in popularity, but the research supporting their efficacy is shaky.

For over a decade, fish oil has been touted by doctors, nutritionists, and armchair health enthusiasts alike as a near cure-all for health. Whether you have heart disease, depression, diabetes, or joint or skin problems, or you just want to stay healthy and prevent nutrient deficiencies, somebody has probably told you to take a fish oil supplement.

The general notion was that it might help, and at the very least, it couldn’t hurt. Unfortunately, that isn’t necessarily the case.

Does Fish Oil Really Prevent Heart Disease?

It’s safe to say that the benefits of fish oil supplementation for heart health have been significantly overstated. As I mentioned earlier, studies initially found that fish oil was beneficial for heart disease, particularly over the short term and for secondary prevention. (1)

But a majority of the evidence available now suggests that fish oil provides no benefits for preventing or improving heart disease.

For example, two randomized controlled trials (RCTs) published in 2010 found that in adults with preexisting heart disease, long-term supplementation (three-plus years) with fish oil had no significant impact on cardiovascular end points. (2, 3)

A few other trials looked at the effect of short-term fish oil supplementation on atrial fibrillation, and none of them found that fish oil improved patient outcomes. (4, 5, 6)

A meta-analysis of RCTs in 2012, focusing on cardiovascular end-points, found that fish oil did not reduce cardiovascular events or death and concluded that the evidence does not support using fish oil supplements for the secondary prevention of heart disease. (7)

Three other meta-analyses published since then came to similar conclusions. (8, 9, 10)

Some studies do still come up with positive results. For example, one meta-analysis published in 2013 found a protective effect of fish oil for preventing cardiac death, sudden death, and myocardial infarction. (11)

Is it possible that fish oil is beneficial for one person and harmful for another? #fishoil

But there are also studies with negative results. Back in 2010, I wrote an article highlighting one study where long-term fish oil supplementation resulted in an increase in heart disease and sudden death and another that found increased LDL levels and insulin resistance in people who took 3g per day of fish oil. (12, 13)

Overall, the majority of studies show neither benefit nor harm from supplementing with fish oil for heart disease.

Does Fish Oil Improve Metabolic Syndrome?

Metabolic syndrome is a collection of symptoms and biomarkers that often precedes heart disease or diabetes.

On the positive side, a recently published RCT found that in adults with metabolic syndrome, supplementation with 3g/d of fish oil along with 10 mL/d of olive oil for 90 days improved several blood markers. This includes a statistically significant lowering of triglycerides and LDL cholesterol, an improvement in LDL/HDL ratio, and improved markers of oxidative stress. (14)

It’s interesting to note that the fish oil plus olive oil group had better results than either the fish oil or olive oil group alone. One possible reason for this is that olive oil is rich in antioxidants and may have protected against the potentially greater risk of oxidative damage from consuming more polyunsaturated fat.

On the negative side, a recent study in women with metabolic syndrome found that 3g/d of fish oil resulted in an increase in LDL cholesterol, blood glucose, and markers for insulin resistance after 90 days, although they did observe a decrease in blood pressure. (15)

And in overweight men, supplementation with 5g per day of krill and salmon oil resulted in increased insulin resistance after eight weeks, compared with a canola oil control. (16)

Finally, an impressively large RCT involving over 12,500 patients with diabetes, elevated fasting glucose, or impaired glucose tolerance found that supplementation with 1g/d of omega-3s for six years did not reduce disease endpoints compared to placebo. Endpoints measured included incidence of cardiovascular events, death from cardiovascular events, and death from all causes. (17)

As you can see, the evidence for fish oil supplementation for metabolic syndrome is mixed, with some studies showing a benefit, others showing harm, and still others showing no significant effect either way.

Can Fish Oil Prevent Cancer? Or Does Fish Oil Cause Cancer?

Many of you probably recall headlines from 2013 proclaiming that fish oil may increase the risk of prostate cancer (18). But despite the extensive media attention garnered by the study, it’s actually one of the weaker cases that have been brought against fish oil.

Believe it or not, the study in question actually had nothing to do with fish oil, or even omega-3 supplements. The researchers simply measured circulating levels of omega-3 fatty acids in men with and without prostate cancer and found that men with prostate cancer tended to have higher concentrations of omega-3s in their blood.

There are several reasons this could be the case; for instance, some evidence indicates that having prostate cancer might itself increase blood levels of omega-3s, or that certain genetic polymorphisms can increase both circulating omega-3s and cancer risk.

It didn’t take long for other researchers to publish a slew of comments pointing out these possibilities, but the media had already taken the “fish oil causes cancer” stance and run with it.

More recently, a meta-analysis found that in general, omega-3 consumption is associated with a decreased risk of prostate cancer, but that the correlation is too weak to be statistically significant. (19) In 2016, a massive meta-analysis looked at 44 studies and concluded overall that higher omega-3 supplementation had no effect on prostate cancer mortality (20).

A handful of reviews found that fish oil intake was associated with a lower risk of breast cancer, although no distinction was made between fish oil supplements and fish consumption. (21, 22) And one RCT published in 2012 found that supplementation with 600mg of omega-3s per day had no effect on cancer risk in men, but increased cancer risk in women. (23)

As with heart disease and metabolic syndrome, the research on omega-3 and fish oil supplementation on cancer is decidedly mixed.

High Levels of Oxidative Products Found in Fish Oil Supplements

Recently, attention has been drawn to the quality of over-the-counter fish oil supplements. Long-chain polyunsaturated fatty acids, including DHA and EPA, are especially susceptible to oxidation due to double carbon bonds at multiple locations.  Light, oxygen exposure, and heat can all contribute to oxidation. Oxidized lipids have been linked to a number of health issues, including organ toxicity and accelerated atherosclerosis—the exact opposite outcomes usually desired by those who supplement with fish oil. (24)

In 2016, the top three selling fish oil supplements in the United States were shown to have oxidation levels up to four times higher than recommended “safe” levels. (25) One caveat of this alarming study is that oxidation levels were normalized per 1g of omega-3s in the supplements, instead of the industry standard of normalizing per 1g of fish oil. Although this does inflate their three measures of oxidation, all three fish oil brands were still above acceptable levels of peroxidase and TOTOX levels, while one (instead of the study’s reported two) was above acceptable anisidine levels if instead normalized per 1g of fish oil.

As oxidation level measurements of omega-3 supplements have increased over the last several years, this has been the common finding. Studies examining fish oil supplements available around the world, including in Canada, New Zealand, and South Africa, consistently show that a vast majority (up to 80 percent!) exceed at least one of the measures of acceptable oxidation levels. (26, 24, 27) Also noteworthy is that most of these supplements contain lower levels of DHA and EPA than the labels claim, probably partly due to oxidation.

Furthermore, the most recent study from 2016 demonstrated that over-the-counter omega-3 supplements had a decreased ability to inhibit small, dense LDL oxidation in a laboratory setting compared to pure omega-3 fatty acids. (25) This means that whatever supposed benefits omega-3 supplements should have on blood lipids could likely be completely counteracted by the oxidized lipids also contained in the pills. Overall, I am quite wary of most over-the-counter products out there.

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Should You Take Fish Oil?

To avoid making this article so long that nobody will read it, I haven’t included research on fish oil and other aspects of health, including mental health, skin health, pregnancy, and cognitive function. As you might imagine, the research on fish oil supplementation to prevent or improve these conditions is also somewhat mixed, with some studies showing significant benefit and others showing no change.

This is certainly an important topic, and I’m glad to see such a strong interest in it in the research community. I will continue to follow the literature and update my recommendations if and when new evidence comes to light, but for the time being this is what I would suggest:

If you are generally healthy, the best strategy is to consume about 12 to 16 ounces of cold-water fatty fish or shellfish each week. When possible, whole foods are always my first recommendation. Most studies show an inverse relationship between fish consumption and heart disease and mortality, so while fish oil may not protect you, eating fish does seem to. Perhaps this is because fish and shellfish contain many other beneficial nutrients that fish oil does not, including selenium, zinc, iron, and highly absorbable protein. (Fortunately, most cold-water fatty fish and shellfish are also low in mercury and other toxins, and mercury in fish may not be as big a problem as some have led us to believe.)

If you don’t eat fish (for whatever reason), I’d suggest supplementing with 1 teaspoon of high-vitamin cod liver oil. In addition to about 1.2 g of EPA + DHA, it is rich in the active forms of vitamin A and vitamin D, both of which are difficult to obtain elsewhere in the diet. There are very few studies suggesting the possibility of harm from supplementation with 1 gram or less of fish oil per day, and so I think one teaspoon of cod liver oil a day is likely to be safe even for those eating fish regularly—and beneficial for those not eating liver or other foods that contain active vitamin A. My current favorite cod liver oil is Rosita Extra Virgin Cod Liver Oil, as this company has consistently demonstrated very low levels of oxidative products from independent laboratory testing.

Based on the evidence I’ve reviewed in this article, I would not recommend consuming high doses of fish oil (i.e., more than 3g/day) over the long term. If you do choose to take a higher dose of fish oil, I would make sure to consume plenty of antioxidant-rich foods, like olive oil; blueberries; nuts; dark, leafy greens; and dark chocolate.

I think we still have a lot to learn about this subject. One of the challenges is that the effects of polyunsaturated fats on overall physiology are complex and probably depend on multiple factors that can vary individually, including uncontrolled oxidation, eicosanoid production, cell membrane effects, and signal transduction via specialized fatty acid receptors (i.e., PPAR receptors).

This could explain why we see such a wide variation in study results. Is it possible that 3g/d of fish oil is beneficial for one person and harmful for another? Absolutely. Unfortunately, at this point it’s difficult to predict that individual response with accuracy and certainty, so I think the conservative approach I suggested above is probably the most sensible until we learn more.

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Join the conversation

  1. I’m kind of.. fishiovore..

    I live in coastal town in Turkey and I eat 300 gr around mostly sardines, anchovies, european seabass every dinner on my IF/Paleo way and I think it’s not necessary but I’m still thinking about fish oil supplementing to boost my heart health.

  2. Great article, but very interesting that FCLO (Fermented Cod Liver Oil) is not mentioned as a superb alternative. At least the products from Green Pasture. Their products are sold worldwide, and they are recommended by the Weston A. Price Foundation.

  3. Sorry, I couldn’t even open myself up to this. It’s unfortunate that I’m overwhelmed with all the changing information about food and supplements. Maybe another day I will process this.

    • Hi Jessica. Completely understand. See my response below and it helps to take a step back and simply eat nutrionally dense foods :))

  4. It was suggested to me 5 years ago to take fish oil because i was always coming down with colds and viruses and i havent had these conditions since

  5. One missing factor in this is the ratio between omega-6 and omega-3 fatty acids in a person’s diet. There is plenty of evidence that humans evolved on a diets with a ratio of around 2. Western-type diets typically have many-fold more omega-6 than this. Could it be that where fish oil has given positive results, it is counteracting excess omega-6 intake. For those with low omega-6 intake, a moderate to high intake of fish oil could balance the omega-6 or even induce an omega-6 deficiency. See for example Gibson et al. Maternal and Child Nutrition 7 (suppl 2) 17-26 (2011).

  6. You should read the books and articles published by Dr Barry Sears. He commonly skewers many of the negative studies on omega 3.

  7. I was taking about 4.5g of a liquid fish oil (recommended dose on the bottle) when I was pregnant with my third. I ended up having what is quite a normal bleed from the edge of the placenta, but the trouble was, it didn’t clot. It pooled into my womb and then formed a large 10cm clot. The doctors told me that when my body tried to break that clot down, it released the same hormone that induces labour. I started contractions at 22 weeks and 6 days. Thankfully it stopped and with 4.5 weeks bed rest and stopping the fish oil, I managed to hold the pregnancy and even lasted till full term. There was no definite cause identified. I was healthy, fit, had no history of clotting disorders anywhere in my family and I had had two very normal healthy pregnancies already. The only thing that made sense to me was the one article I found that said more than 3g/day of fish oil can cause clotting issues. It freaked me out to the point that I can’t bring myself to take it anymore, even though I don’t plan to get pregnant again. I run a home nutrition business now and just try and get the balance I need through the foods I eat.

  8. My functional medicine doctor wants me to take almost 5 g of fish oil daily, due to familial hypercholesterolemia. When I take about half that amount, I notice a lot of blood thinning effect.

    Any advice? Thanks.

      • Um, thanks. I was already aware that fish oil (or a diet very high in fish) increases the risk of bleeding/stroke. But it’s always interesting to see why.

        I was really looking for advice regarding the familial hypercholesterolemia, and whether the benefit of fish oil outweighs the risk in that situation.

        • Well that’s an interesting question. From the Framingham study, those with the highest cholesterol actually where more fit and survived longer and healthier so one wonders why it needs “treatment” in the first place.

        • It’s a very rare disease (1 in 500) so are you sure of the diagnosis and have the genetic testing to say it’s real?

          • I personally only know of one family member who had the genetic testing to confirm (I should mention that it is the heterozygous form). Multiple family members on that side have cholesterol numbers which typically make our doctors panic (one is in the 700s despite healthy diet, being very active, and thin). Every doctor I’ve seen has said based on my lipid numbers and family history, it is familial hypercholesterolemia. Although I am aware it’s possible for other health issues to raise cholesterol levels, it just doesn’t seem likely to be the main cause in this case.

            As for why treat it in the first place, I would have to say the answer is fairly complicated, but with my personal numbers being very high, and a strong family history of atherosclerois, heart disease, and early death, it isn’t something I can ignore. I realize that for most people, oxidized cholesterol is the problem, not cholesterol itself. With extremely high total cholesterol and high LDL particle numbers, and only half of my LDL receptors in working order, it seems quite likely that the LDL particles are in circulation for plenty of time for oxidation to happen.

            1 in 500 might be rare, but at least it seems almost everyone has heard of it. I have a different disease that is considered rare, and took quite a while to get diagnosed as many of the doctors I went to had never seen it.

            Thanks for your input, it is always nice to find out more information and more opinions never hurt when making health decisions.

  9. Chris,

    Do you think the source of the fish oil might have a significant effect on the outcome of some of these studies?

    I wonder if the quality assurance of the fish oil (that it is captured in an oxygen free environment) might negate the negative or marginal results across the literature.


  10. I noticed you didn’t discuss fish oil and mental health. I suffer from bipolar disorder and was suffering terribly for years. After I started taking fish oil supplements I noticed a great improvement of my disorder and stabilised quite well. My mood fluctuations are no longer as marked as they used to be and I am much better able to manage the swings now.

    • I did mention in brief that the research on fish oil for other conditions, including mental health, is mixed. That said, I also suggested that it’s clear that there are many individual factors that are likely to determine response to fish oil, and some will benefit. You seem to be one of them, which is great—provided you are not taking a very high dose that could promote oxidative damage and cause other problems down the line. That would be my only concern.

    • May I ask what brand and how much you take? I believe that taking the omega helps with my brain fog due to my AI issues and my change of life issues. I also suffer from depression and would really like to feel better as the meds only help slightly.

  11. That is interesting reading, but I have to say that earlier this year I started suffering with arthritis in my right hand. I have taken fish oil capsules for years, but switched to liquid fish oil (1 tsp daily) and within 2 days the pain disappeared. It could of course be a coincidence, but I’m keeping taking the liquid fish oil.
    We do eat a lot of fresh vegetables every day and eat a healthy diet, so I’m hoping that taking the omega 3’s adds to that. We eat more fish in winter, but in winter (now in New Zealand) we don’t eat fish very often).

      • Well he is a PhD in Nutritional Sciences and is currently Assistant Professor of Health and Nutrition Sciences at Brooklyn College, part of the City University of New York

          • Seriously?
            And this is coming from a person, who exclusively posts on the topic of omega-3s, bashing them to the best of his abilities and promoting some product (if one clicks on his name). Wow…forget Chris Masterjohn, let Dr Jeff (if that is even your real name) lead the way…and sell some products.

            • So I want to apologize if it seems I was bashing Dr. Masterjohn but his article quoted above has a number of inaccuracies about it that need to be addressed. The first sentence of his article does not confer with known biochemistry

              (B.Alberts, 1994) (R.K Murray, 2003) (Simmons, 1998) (R.K. Murray, 2003) (Hall, 1996)

              “Current reviews and textbooks call the omega-6 linoleic acid and the omega-3 alpha-linolenic acid “essential fatty acids” (EFA) and cite the EFA requirement as one to four percent of calories. Research suggests, however, that the omega-6 arachidonic acid (AA) and the omega-3 docosahexaenoic acid (DHA) are the only fatty acids that are truly essential.” He fails to take into account that 95% of EFA’s stay in their native form and are incorporated into the cellular and mitochondrial membranes and are extremely important to their proper functioning (Zhou, 2009) (P. L. Goyens, 2006)

              “An excess of linoleate from vegetable oil will interfere with the production of DHA while an excess of EPA from fish oil will interfere with the production and utilization of AA. EFA are polyunsaturated fatty acids (PUFA) that contribute to oxidative stress. ” Here one has to realize that all the linoleate (the salt of linoliec acid) from the vegetable oil most of us get in our food is highly adulterated, changing how it functions both intracellularly and extracellularly. For example see: http://bit.ly/1Cu0KP2. This is why I have issue with the article posted above.

              Again, I apologize, but it is an area I’m passionate about and want to see the right information out there.

              Works Cited

              Zhou, R. C. (2009). Imaging Incorporation of Circulating Docosahexaaenoic Acid [DHA] into the Human Brain Using Positron Emission Tomography. Journal of Lipid Research , 50 (7), 1259-1268.

              B.Alberts, D. J. (1994). Molecular Biology of the Cell (Vol. 3). New York, New York, United States: Garland Science.

              Hall, A. G. (1996). Textbook of Medical Physiology. New York: W.B. Saunders Co.,.

              P. L. Goyens, M. E. (2006). Conversion of Alfa-Linolenic Acid in Humans is Influenced by the Absolute Amounts of Alpha Linolenic Acid and Linoleic Acid Diet and Not by their Ratio. American Journal of Clinical Nutrition , 84 (1), 44-53.

              Simmons, G. H. (1998). Principles of Medical Biochemistry. St. Louis, United States: Mosby, Inc.

              R.K Murray, D. G. (2003). Harper’s Illustrated Biochemistry. New York, New York, United States: McGraw-Hill.

              R.K. Murray, D. G. (2003). Harper’s Illustrated Biochemistry. New York: McGraw-Hill.

              • Got give it to you Jeff you are relentless with straw man arguments, sowing confusion and deliberately misrepresenting others points.

                • You have to realize there is a basic misconception of lipid metabolism running rampant in the literature and is affecting all the basic recommendations which is affecting real people’s health. 25% to 33% of the cell membranes (both the cell and more importantly, the mitochondria) are the NATIVE form linoleic acid. The very substance that gets highly adulterated in todays modern processing techniques. This explains many of the modern ailments we see today in the population. The assumptions of the man make him “straw”.

      • If you think Dr. Masterjohn knows nothing of biochemistry, you’ve no credibility with me. For anyone who is interested, Dr. Masterjohn has written an excellent blog, called The Daily Lipid for years. He has as well written articles for The Weston Price Foundation, and I’ve found his articles there to be well reasoned. Among other things, he has also been interviewed by Dr. Joseph Mercola and that interview can be seen on you tube.

        • I’m just saying the particular article quoted had some basic errors in it. As stated by the author, he is an expert in fat soluble vitamins and glutathione.

  12. My husband kept breaking blood vessels in his eyes when he did any kind of physical exertion. We finally realized it was the fish oil supplement he was taking (research). He stopped taking it and the blood vessels in his eyes stopped bursting. Just to be sure, he started taking fish oil again, and it started happening again. We think it thinned his blood too much.

  13. Great article, Chris.

    In noticed you mentioned EVCLO. Do you still recommend Fermented Cod Liver Oil? Is EVCLO superior to fermented cod liver oil?

  14. i have taken it several times in the past few years. I was experiencing horrible insomnia and stopped taking the fish oil. Problem solved. I told my doctor, and she told me that fish oil can cause insomnia. Thanks, doctor. This was after she had offered me Ambien. I tried it again a few weeks ago. In the morning, lower dose. It caused horrible anxiety! Did some research and found, while not common, it can affect people the way that it’s been affecting me. Horribly. No more fish oil for me.

    • I got insomnia from eating – for a good while – salmon daily. This wasn’t a good idea anyhow, but I was surprised how extreme my insomnia got. (I shouldn’t be surprised, as I’m a ‘hyperresponder’ anyhow – reason I’ve ceased taking almost all supplementation over the years). I now eat just a little (fat fish) once or twice a week. My insomnia does flare easily: too much sugars, too much caffeine, eating/snacking too late (after seven/eight), blue light (solved by not watching TV at night and F-Lux, a freeware app), etc.

  15. Thanks Chris.
    I took Fish Oil supplements for several years but stopped 2 years ago for 2 reasons. The first is that I developed Seborrheic Keratosis, loosely known as Liver Spots, although they do not appear to be associated with Liver function. They went away after I stopped the Fish Oil. Also my Cholesterol readings remained high with ratios not where I would like them and, despite controlling my diet with less refined carbs, which had helped significantly in the past before I started taking Fish Oil, I could not improve my readings. Now I take Flax Seed Oil in moderation and that seems fine with no Liver Spots. The second reason was the 2013 report mentioned in your article relative to Prostate Cancer.

  16. Chris, I’m curious what your take on Fermented cod liver oil is? It seems like most sources recently believe it is a better option than cod liver oil. Would you agree?

    • I’m taking Green Pastures Blue Ice fermented cod liver oil and butter oil and would be interested in a reply from Chris regarding fermented products

  17. Thank you for the article, the tide on fish oil is beginning to turn, it’s so hard to shake people’s belief system and get them to look at the science. Supplementing with the proper 18 carbon, unadulterated versions of Omega-3 and Omega-6 is the way to go and leave our poor, dwindling fish stocks alone.

  18. Thanks for the reassurance. I stopped taking fish oil several years ago. I started taking fermented cod liver oil every day about 6 months ago. Instead of fish oil, I developed the habit of eating salmon every other day, mostly as salmon salad. I had heard that taking fish oil should be considered a temporary measure until you got your diet to a good place. By that logic, continuing to take fish oil would suggest that you are not eating right. Maybe that is why research about the value of long-term supplementation is mixed.

  19. Hi,

    That’s very interesting. I’ve always been thinking eating fatty fish was very important, especially for brain health.

    Does this mean could be beneficial to focus less on salmon, trout and other fatty fishes, and eat more other fishes to increase food diversity, even if that ultimately means ingesting less EPA/DHA?

    When saw a naturopath practitionner (had IBS and insomnia), I was always told to add a fish oil supplement to my diet, until I answered that I was already eating fatty fish 3-4 times a week.



    • Hi Remy, I learned that consuming a fish’s EPA/DHA isn’t what we should be striving to do. Producing our own is the key and the only thing that makes that happen is plant oils. We found a product that has pumpkin seed oil, flaxseed oil, borage oil, and coconut oil, with turmeric. This combination is the perfect balance of omega 3, 6, and 9. Bonus is that turmeric needs these oils to be an effective anti inflammatory. Check out http://www.truthmatters.mytouchstoneessentials.com/product/wellspring/

      • Hemp seed oil is also the perfect balance of omega 3,6, and 9 that humans need. I use it on salads.

        • Actually no: the ratio o3:o6 in unbalanced towards the o6.

          It also contains ALA only, you are missing DHA and EPA.

      • Borage oil doesn’t have enough bioavailabilty and you should not turn liquid fatty acids into a powder, best to keep them in their natural state.

      • Not all humans can efficiently make the conversion ALA to DHA and EPA. Actually they are a minority.
        So yes, getting the whole set of o3 from food sources IS one of our priorities.

        • Actually, it’s a steady state reaction so the rate of conversion is irrelevant, it’s a common mistake that many nutritionists make.

        • Less than 0.5% of ALA is converted to DHA, and that’s in a healthy person. If deficiencies of any of the nutrients required for the enzymes in that conversion pathway are deficient (which is common, especially in vegetarians), the amount that is converted is probably lower. This is why I continue to believe that eating pre-formed EPA and DHA is important.

          • There are many societies that have no access to EPA/DHA and do quite well. The vegetarians may end up deficient if they cook everything. We only need 10mg of DHA a day, so even a 0.5% conversion rate is adequate if your intake of ALA is fine. Besides which, the adequate intake of unadulterated LA is much more important to health.

                • Exactly, and they don’t rely on vegetable sources of omega-3.

                  The meat they eat is of good quality, they eat the brains and the internal organs of the animals which are loaded with good quality omega-3 fatty acids.

                • The animals are getting their nutrition from plants, which are the plant based 18 carbon Omega-6 (LA) and Omega-3 (ALA) not DHA/EPA, we take advantage of their ability to graze large ares to concentrate the nutrients in their tissues that we then consume and allow us to put more resources into developing bigger brains etc. Nature has a very good balance and reason for doing things, we can’t outsmart it.

                • No Jeff, you didn’t understand my previous post.

                  Or, alternatively, you understood it, you realised you are wrong and are trying to win by exhaustion, which is actually the case. I have no time for you.

            • Remember, consuming deep water fish or their oils literally goes against millions of years of evolution where they would never have been available to us as land animals.

              • I agree with you for the fish oil. When you are right I don’t argue.

                Supplements are needed for unblocking difficult situations caused by other bad habits that go against our evolution. Not as a replacement of good food.

      • In New Zealand anyway the basic regular diet is far too high in Omega 6.
        So best to avoid these products, some of both double strength omega 3 fish oil and Olive Oil or flax is a good combination BUT it is different for every individual and each must find the balance for themselves ,do not listen to anyone that hands out information to people from a list without understand who thy are and what that person requires to balance self

      • I’d skip the Omega six. It’s over represented in modern diets everywhere and we likely get much more than we need already. I wouldn’t add more with a supplement.

    • Eating fatty fish has a different effect than fish oil, which is one of the main points of this article. There is a huge amount of research linking consumption of shellfish and fish with positive health outcomes. This article does not in any way detract from that research, and I still recommend consuming fish and shellfish.

      • What’s the difference between the oil in the fish and the oil in the capsules? Is the fish oil in capsules likely to be rancid? Or is there something missing?

        • The difference seems to be in what’s “around the oil” : in capsule there’s the oil only, in fish, there are plenty of other nutrients – vitamins, minerals, proteins, and probably other as well (would it be called “carnonutrients”?)

          Thanks for your replies. I don’t think supplementing with oils in pills is best (I’m already using coconut and olive oil to cook daily), and indeed, ALA don’t easily convert to EPA and DHA, like beta-carotenes to vitamin A. But I will focus less on fatty fish and more on diversity.

          • Good point. Supplements are not meant to replace a healthy diet, I am speaking of supplements general of course (EFA, but also vitamins, minerals, enzymes, etc).
            They are indeed useful in some cases when there is an obvious deficiency but their use must stay temporary.

      • HI all… I eat Wild Salmon many times each week. I have seen many healthy benefits . Are there any cause for concern ?

    • How did your naturopath diagnose you with an EFA deficiency?
      Eating them is not enough. Did s/he test whether you correctly absorb them? (IBS may be a sign you are not digesting and absorbing them and they rancidify in your intestine).

      Another important thing is the way they are prepared (if you overcook fish it is like not eating n-3 at all, they become rancid).

      Supplementing is the last resource, always.

      • My son in law has a seafood allergy. I am wondering how he can obtain Omega 3s in his diet. Would a cod liver oil supplement likely be an allergen too?