The standard Western diet is sadly lacking in omega-3 fats. Most of the recommendations we hear are to increase our intake of omega-3s by eating fish a few times per week. Most people who do eat fish eat tuna, the most readily available fish around that contains a halfway decent level of omega-3 fats.
But news reports over the past several years have put a lot of us off of tune, at least the canned variety, with reports of how much mercury such tuna contains. MD and I have opted to get our tuna as sushi grade tuna that we get either at Japanese restaurants or by purchasing it at a natural foods grocer and making our own sashimi. Now comes a report that gives us pause.
The International Herald Tribune published an article story showing that even sushi-grade tuna is crawling with mercury, which makes fish eating now a Faustian bargain. We can get the omega-3s, but at the expense of a ton of mercury.

Recent laboratory tests found so much mercury in tuna sushi from 20 Manhattan stores and restaurants that at most of them, a regular diet of six pieces a week would exceed the levels considered acceptable by the Environmental Protection Agency.
Sushi from 5 of the 20 places had mercury levels so high that the Food and Drug Administration could take legal action to remove the fish from the market. The sushi was bought by The New York Times in October.

But maybe this is just a freaky sample. I’m not so sure. And the article goes on to state that the more expensive the tuna, the greater the contamination.

These findings reinforce results in other studies showing that more expensive tuna usually contains more mercury because it is more likely to come from a larger species, which accumulates mercury from the fish it eats. Mercury enters the environment as an industrial pollutant.

Now, I love sushi (actually, MD and I almost always opt for sashimi, which is the raw fish without the sticky rice, as shown in the photo above), but I’m not really willing to sacrifice my health for it. I get most of my omaga-3 fat from the krill oil that I take daily. Krill are tiny shrimplike creatures that are at the bottom of the food chain, and, thus, don’t concentrate mercury in the same way that fish do. And krill have a unique phospholipid structure to their fatty acid bonds that makes them much more absorbable, preventing the fishy smelling belching that fish oil capsules sometimes cause. If you want to get your omega-3s as tastelessly and painlessly as possible – and without the risk of mercury toxicity – you can’t go wrong with krill oil.  Even a few years ago krill oil wasn’t readily available, but now you can find it all over the place.  And it’s not all that expensive.   So, to get your daily dose of omega-3, down a krill oil gelcap or two and forget the recommendation to eat fish several times per week.


  1. This advice seems to be an extension of the Omega-3 advice in your Protein Power Lifestyle book that puzzled me from the moment I read it. You mention several times to take cod liver oil by the spoonful for Omega-3’s but don’t mention fish oil except to dismiss fish oil capsules.
    But why not take molecularly distilled fish oil by the spoonful?
    There’s no mercury, it tastes like lemon, the smell of the open bottle will tell you right away if it’s gone rancid (no waiting for fish burps), you get an excellent balance of EPA and DHA, you don’t have to worry about how much Vitamin A you’re getting (try to get a daily dose of 4g Omega-3’s from cod liver oil without a toxic dose of Vitamin A), and it’s much more affordable than Krill Oil per mg of EPA/DHA.
    Not very many downsides. Lots of upsides.
    When I recommend your book to others, I often add the caveat that back in 2000, you two hadn’t heard of simple bottled fish oil as a superior source of mercury-free Omega-3’s. But this posting really makes me curious: it’s now 2007, so what’s holding you back from recommending simple fish oil by the spoonful?

  2. Hi Mike,
    I’m with you and MD about sushi. Even long before my low carb existence I found sashimi a much more interesting taste sensation, particularly in combination with the soy, wasabi , pickled ginger, daikon etc.
    The thing that gets me about tuna apart from possible heavy metal contamination is how little fat comes with it (any tuna can in the western world proclaims this as a virtue!). It is sometimes called the chicken of the sea, but what we tend to eat would be the equivalent of skinless chicken breasts (something I really can’t stomach these days (I blame you!) unless covered in a very creamy sauce! Anyway 100g of tuna would give you less than 5 g of fat, most of that saturated or monounsaturated and only a tiny fraction of the rest would be the omega 3s we seek. So you are better off to go for salmon or some other (smaller) cold water fish which you can eat with the fatty skin (like with chicken, the best bit) and with probably less issues with mercury.
    But I agree about the krill oil too, or failing that a fish oil from a reputable mercury free source.

  3. I’ll have to look for that oil…..right now I’m getting my omega’s in a flax/borage gel cap. It does make a difference in how I feel. Mad Scientist aka dh can always tell when I’ve been forgetting them….he says I get on the witchy side……but then again…he is Mad.

  4. I have my doubts about the needs to increase polyunsaturated fats intake (even if it’s the omega 3).
    I tend to believe that a non-carb diet, high in animal fat, beef fat in my case, will let the body do its job rightfully, that is converting the little amount of ALA and other EFA precursors to whatever is needed.
    Is there a reason why the body would need a high, constant influx of fats that serve a structural function when it is well protected by antioxidants (such as Vitamin D, a membrane antioxidant)?
    Fighting a lack of omega 3 in the cells with high-dosage sounds a bit like eating more frequent meals to prevent the low blood-sugar induced by high-carb diet.

  5. I started taking krill on your reco back in late Oct, and I’m crediting it with the apparent vanishing of my pre-menstrual symptoms. Which wasn’t the benefit I was expecting. So I’m very pleased. And if I’m wrong that it’s the reason for the disappearance of my crampy/bloaty/sore-breasts thing, don’t tell me. I’m happy.

  6. I know you’re not answering questions anymore, but what’s the proper daily dose? I see numbers all over the place and it would be nice to have a simple answer.

  7. The fish that I eat in significant quantities is sardines–canned in olive oil. Being small fish they haven’t had time to accumulate much mercury–I think.

  8. I reread your 2006 post on krill oil and I just ordered it from Amazon on a monthly automatic reorder. How’s that for having faith in you.
    I’ve long wondered whether you’re familiar with Dr. Bert Herring’s Fast-5 book/forum on intermittent fasting. I’ve tried it because it makes sense but it never felt right for my body.

  9. Speaking as someone who just plain likes canned tuna, it’s been sad to see the quality of grocery store tuna deteriorate over the years, not to mention the troubling increase in mercury. However, on the recommendation of a fellow on a diabetes bulletin board, I started ordering canned tuna on-line from this little co-op of Oregon fisheries. They claim to keep the mercury content low by only using younger tuna. To me, it tastes like olden-days tuna, canned in it’s own juices — not water or oil. No worries about a mass market here, it’s **way** expensive — between $6 and $7 for a 7.5 oz can. Since I can make several meals out of this, it’s worth it to me.
    Just wanted to share in case there are other die-hard tuna-lovers out there. — Mary

  10. @BillyHW: I dunno about you, but I have found news sources that exist solely to rebut other news sources to not be the best source of news. And this is from me, who at many times in my life, have been accused of existing solely to contradict others. That said, The NY Times says mercury is in the sushi fish. The National Fisheries Institute is the source for the contrarian opinion? This feels like something stinky in Denmark and it’s probably not rancid fish oil. The other source for the Timeswatch article is The Center For Consumer Freedom, a well known front for the restaurant, tobacco and alcohol industries:
    I know the Times might be a little shoddy in reportage here and there, but timeswatch is essentially shilling for industry. I dunno who you trust more, but I like to follow the money. The times makes little on this story, Fisheries and restaurants would lose big. Ergo: they have the most incentive to lie.
    I would hope that frequent readers of this blog would think to follow the money, look a little deeper, and not just dismiss the Times because it’s the Times and supposedly liberal or something.

  11. Fascinating annecdote by Seth Roberts:
    “There’s a group at the University of Cincinnati that did an Atkins vs. low-fat study and they found that the Atkins people lost twice as much weight and they liked the diet much better. I was interviewing the dietitian who did the study. She had agreed to talk to me but she was very hesitant — she didn’t offer up any information. Finally, at the end of the interview, the one thing she offered freely: I asked her who funded it and she said the American Heart Association.
    I said, “Well, I have to give them credit for funding it.”
    She said, “Don’t. They funded it because we proposed it as a study that would refute the benefit. And when we found that the Atkins diet really worked and worked better than the low-calorie diet, now we’re trying to get money to look further into it and they won’t give it to us.”

  12. Krill oil for omega-3’s because they’re found at the bottom of the food chain? How much money is the krill oil supplement company giving you for that recommendation?
    Plant foods are at the ultimate bottom of the food chain and they are loaded with omega-3’s, monounsaturated fat as well as fiber. You can purchase plant foods such as nuts, avocados, and beans at your local grocery store for a lot less money – and they taste better too.

  13. Farmed amberjack species (hamachi, Kona kampachi) are still good lower-mercury sources of tasty sashimi (and omega3s). Kona kampachi is probably the better choice over anonymous hamachi (although a more expensive one) since it’s known to be sustainably farmed with an eye to maximizing omega3s and minimizing mercury. Wild salmon is still good for you with not a horrible mercury load (suitable for eating once a week if I remember correctly). Mackerel varies by species and region, but I’m pretty sure the mackerel we get here in CA is not terrible for mercury content. Halibut sashimi is popular here (SF area) in season, and is also a lower-mercury choice.

  14. Bronwyn, accusing Dr. Eades of shilling for money is serious. Is that rhetorical sarcasm, or are you making an accusation?
    If it’s the latter, bring some supporting facts and go to town.
    If it’s the former, it’s inappropriate. It’s not civil discourse.

  15. Michael,
    Please do yourself and the rest of us a favor and don’t approve attack posts from Vegan/PETA nutritionist trolls who are trying to link-promote their bean blogs (Bronwyn Schweigerdt above.) Especially when they’re attacking your honesty!
    Sorry, but I can’t believe her gall!

  16. Bronwyn,
    Not all Omega 3s are created equal. The most desirable for adults is EPA, and it is very rare in earthly plants, but it is available in sea plankton in vast quantities. It is also abundant in krill that eat sea plankton.
    There is very little difference between getting you desirable Omega 3s (EPA and DHA) fof human consumption perspective between krill and fish, but there is a difference in impact on the environment. Fish oil derived from large fish (salmon) has the highest impact, getting it from smaller fish has lower impact, getting it from krill has the smallest impact.
    By the way, the omega 3 sources you mention have the highest concentration of the least desirable Omega 3 – ALA (alpha linolenic acid).
    I would suggest you spend more time getting familiar with the basics (above) and less time throwing stones.

  17. Dr Mike,
    I, for one, am willing to die for sushi! LOL
    I take Krill Oil (two capsules), Carlson’s fish oil (No A and D) – 1 teaspoon and Blue Ice High Vitamin Cod liver oil (natural A and D) – 1 teaspoon per day.
    Cindy Moore:
    Here is the site I think Mary is refering to:
    Philip Thackray

  18. Ross writes -“When I recommend your book to others, I often add the caveat that back in 2000, you two hadn’t heard of simple bottled fish oil as a superior source of mercury-free Omega-3’s. But this posting really makes me curious: it’s now 2007, so what’s holding you back from recommending simple fish oil by the spoonful?”
    I wish it was simple as you think. The trouble with bottled fish oil is that the fish oil is exposed to fresh oxygen everyday. I and my wife finish a bottle in a month. When I open the new bottle there is a large difference in taste. Oxidation is happening – face it. I used to believe that I was able to taste rancidity in time to avoid problems. I am not. My regular fish oil capsules smelled a bit stronger, so I tasted them. Not rancid I thought. But my CRP levels went up. With higher inflammation indicated by a high CRP, I think the cause was “less fresh” fish oil.
    I am working on a better method. Next month I will start a new procedure. I have bought tiny pyrex test tubes that hold one tablespoon of oil. I will empty all of a fresh bottle into the test tubes and seal them with airtight plastic stoppers.
    Maybe the last of the test tubes will taste the same as a freshly opened fish oil. If so, I have solved a sizable portion of my fresh fish oil problem.

  19. “Plant foods are at the ultimate bottom of the food chain and they are loaded with omega-3’s, monounsaturated fat as well as fiber. You can purchase plant foods such as nuts, avocados, and beans at your local grocery store for a lot less money – and they taste better too.”
    It was left out in the above statement the overwhelming quantity of the other EFA (omega 6) that is already prevalent in the current diet. Without fish oil or shore-based diet you’d need a lot of leafy greens and/or grass-fed meat or krill oil to gain the benefits. I assume we all agree that limiting omega 6 intake is another sound strategy.
    How much omega 3 you need is not a simple questionto answer. Why not perform the experiment on yourself? Your memory, reaction time, problem solving skills can all improve with the supplement as well as other inflammation markers such as: gum color (pink not red), gum bleeding after flossing (absence of), blood pressure (lower), etc.

  20. Vesna, she’s not after civil discourse. Writing nasty comments on popular blogs is a proven strategy to get blog traffic for new blogs (which is her real goal.) Dr. Eades probably approved her post in the interest of free speech — I’m guessing he hasn’t yet heard of the strategy.

  21. Philip Thackray — I mentioned the Carvalho site because they select for young, smaller tuna which are hopefully lower in mercury. The Dave’s Albacore site you mentioned sounds like great fish but I didn’t see any reference to lower mercury levels which is the topic at hand. As I mentioned in my post, there are probably lots of excellent independent co-ops out there that sell good fish, including Dave’s Albacore — Mary

  22. Could we ask if le Dr might comment on the Science daily blip about Vitamin D supplements being badly for one perhaps and pleasum ?

  23. Thanks for the discussion, David. That’s a good point about exposure to oxygen, which is why my wife and I buy the smaller bottles of Carlson’s instead of the less expensive (per tbsp) bigger bottle.
    I do have some small 2oz plastic bottles with pour lids that would last the two of us for two days (2oz = 4tbsp). Might be a good way to achieve the same goal you’re talking about. We’ve used them when traveling, and even though they don’t stay as clean as the oil-pour cap does, they get the job done.
    One thing still bugs me though: if the PUFA’s in fish oil are that vulnerable to oxidation, aren’t the PUFA’s in cod liver oil just as vulnerable? So I still don’t understand why the M.D.’s recommend the cod liver oil over the fish oil…
    But thanks for the good points. I do appreciate the thoughtful response.

  24. According to Sandy Szvarc at Junkfoodscience
    New York Times bought tuna from twenty stores and select restaurants and had them all tested for mercury levels. What did it find?
    All of the tuna it tested being sold commercially in New York had mercury levels nearly ten times below the lowest amount that has been shown might ever pose a danger to the most sensitive population (babies and children) with a lifetime of daily exposure.
    So MAYBE, as we frequently find, the headlines and reporting aren’t actually backed up by the data.

  25. About the Vit D study I posted above:
    Dr. Eades is taking a break from commenting. But here is what Dr. Davis from Heart Scan Blog had to say about that study:
    “It refers to the so-called “Marshall Protocol.” Having read his arguments, he mixes science with conjecture and enormous leaps of speculation, all with zero experience in real, live humans. (He’s a “bench” researcher with experience that doesn’t extend beyond mice and cell cultures.)
    It reminds me an awful lot of the pseudo-scientific tangent that misled Linus Pauling and Mathias Rath.”

  26. Tee and krill oil.
    Krill oil is different than fish oil. There is no question yet about the best krill oil. There are lower priced krill oils, but none have NKO’s potency and are unable to compete on a price for potency comparison. Choose your favorite brand or choose Dr Eades’ NKO available on this site.

  27. Basically all good krill oil comes from the same source. Look for “Neptune Krill Oil.” A lot of brands buy from them (Jarrow, Now Foods, etc.). If it’s from a reputable brand, and says NKO on the label, it will be the good stuff.
    The best source for supplements I’ve found is I’ve been buying from them for years now, and they have the best prices and great customer service. (And no, I don’t work for them!) Search for “NKO” and you’ll find a few.
    I should also say that I have turned two friends on to krill oil to lower bad cholesterol. Both of them were having trouble even with medication. They both were amazed at what the krill oil did. One of them lowered it 30% in two months, his doctor was shocked.
    And as for tuna, there are a couple of good sources I’ve found for high-quality tuna and salmon:
    The best canned tuna I’ve ever tasted, and they also go for the younger tuna, with theoretically less mercury. Small company, nice folks.
    They have both canned tuna and canned and pouched wild salmon.
    Neither is cheap by any means, but the quality is really incredible.

  28. @Bronwyn:
    The problem with plant sources is that the Omega-3’s in things like Flax, Kiwi and Almonds are mostly ALA. ALA is not an essential fatty acid. EPA and DHA are the essentials. ALA converts to EPA/DHA. But conversion rates are bad (2%-5% for EPA, 2-15% for DHA). That’s an awful lot of flaxseed to get what a little bit of krill will give you.
    If we’re talking whole foods, you also get around the leaky gut that the vast amounts of fiber in flaxseed would cause you. And, the bulk. It’s volumetrics argument in favor of flax. Fish are the more nutrient dense option, with a better profile of omega-3’s to boot. Ditto for grass fed beef. Ditto for eggs.

  29. Dr Eades,
    I have to say, I understand that you don’t have the time, but I miss your responses. Some posters are “filling in” for you well though. If you have time in the future could you comment on those “Omega 3” eggs? I looked online for info but could find none. I find they have a very mild fish smell that I don’t mind but do we have to worry about fats going rancid during normal egg storage? Do the eggs really have the Omega 3’s that they claim and are they a good choice or a waste of money?
    Already looking forward to the new book!

  30. I checked out Bronwyn’s blog, and she is not someone I would ever consult for nutritional advice. Not only does she advocate the kind of grain-bean feedlot diet that made me fat, she also heartily endorses T. Colin Campbell’s überidiotic, junk science ‘China Study’.

  31. I am weird no doubt, but about seven years ago, I began eating a can of tuna for lunch Mon-Friday. (tuna fillet in olive oil). I did this for three years, with hardly any variation. Then I heard about mercury and had my level tested. It was 10, the upper limit of the lab’s normal range. I began to eat other things, but still eat tuna sometimes. I will have the level tested again soon.
    My point is that I think it takes A LOT of tuna or other fish to get into the toxic range.

  32. I’m not sure if it takes that much mercury to accumulate (probably depends on Vitamin D status as well b/c as you know if you’re deficient, then your body nonselectively uptakes any mineral like Hg++ which looks like Ca++ calcium)…
    Daphne Zuniga of Melrose Place fame is a strong proponent of testing for mercury b/c she became toxic from ‘eating healthy’ with frequent fish. I’ve heard of several other stories as well! My husband’s friend has a brother who is a fisherman in San Francisco Bay. Recently his blood tested 75 for mercury (10 and less is normal). Other people who have canned tuna or Ahi for lunch a couple times a week end up toxic too… I think if Krill oil has < 1ppm Hg (mercury) than that’s actually a better product (and safer to take if you’re conceivable taking them indefinitely/forever) than most purified, filtered fish oil capsules available on the market at this time. Anyone know?
    THANK YOU DR. Eades for another informative, discussion-provoking post!! Keep up the commentary and sharing your insights, I miss your wry wit in the comments section… 🙂

  33. John N,
    I would agree from my experience — if one is on an optimal dose of DHA+EPA ‘seafood’ oils, then one should notice improvement in mental alertness, acuity and sync-ing of the synapses! Since I’ve been taking them for the last 2-3 mos I notice a huge improvement. It is not as if I’m going to join Mensa now (like perhaps some of you here) but I do feel mentally rejuvenated, handle stress better, and sleep is improved. I’ve reviewed some ALA diets and studies, however without fish oils DHA + EPA, the benefits for the brain and heart are apparently not evident. The longest chains (for conductivity) in nature are the seafood oils DHA and EPA. Thanks! g

  34. Mainstream media starting to get it (maybe) on fish oil and the like. Here’s a link from the BBC on a study that showed that arthritis patients who were given cod liver oil cut down their use of antiinflammatories without experiencing an increase in pain

  35. I’ve finally decided to start supplementing my diet with fish oil. I’ve looked into all of the formulations and many of the “pharmaceutical grade” brands. Just when I thought I had decided what I’d used, the question of liquid or pill entered my mind.
    I know the liquids are generally more potent and cheaper per milligram. But I’m wondering about oxidation levels. We all know that if the oil smells really bad it’s probably rancid. But what if it’s not quite to the point that it smells? If the oil is so easily oxidized, won’t oxidation begin and continue as soon as it’s bottled because of the oxygen in the neck of the sealed bottle? Even if i refrigerate it after opening it, isn’t oxidation going on? If it’s a month supply how many free radicals are present after 3 weeks even when properly kept? How significant is the exposure to the free radicals when taking the oil even if only slightly oxidized compared to our everyday exposure? Do the soft-gels confer a measure of protection against oxidation compared to the liquid because the oil is sealed in the capsule?
    The soft-gels provide some measure of protection, but the soft-gels are permeable to oxygen. As are the plastic bottles in which they come. The best way I’ve found to keep fish oil fresh is to buy the soft-gels, then transfer them to glass bottles and keep them in the fridge.

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