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Why Fish Stomps Flax as a Source of Omega-3


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I want to thank everyone for sending in their questions and voting on the next topic. The good news is that there’s a lot of interest in all of the topics I’m researching right now. The bad news is that there was no clear winner.

I’ve decided to go ahead with the series on fish and fish oil, but I may write about thyroid and diabetes simultaneously. I’m also going to experiment with shorter (although I’m clearly breaking that rule here), but more frequent, articles. Hopefully these will be easier for me to write and for you to read.

Finally, stay tuned for the first episode of The Healthy Skeptic audio podcast, coming up next week. I’ll be interviewing Stephan Guyenet, Ph.D, on the subject of obesity and weight regulation. Stephan is a senior fellow at the University of Washington studying the neurobiology of body fat regulation. He’s also the author of Whole Health Source, which is one of my favorite health related blogs.

Before we get into talking about the benefits of fish consumption, or how how much fish or fish oil you should eat, it’s probably a good idea to start with a basic review of the omega-3 fatty acids.

Essential Fatty Acids 101

A fatty acid is a chain of carbon, oxygen and hydrogen atoms with a carboxyl group on one end. Fatty acids are classified on the basis of how many carbon atoms are in the chain, as well as how many double bonds exist within the molecule.

Fish contain a variety of fatty acids, but the ones that are believed to confer the majority of the benefits are the long-chain omega-3 fats eicosapentanaenoic acid (EPA) and docosahexaenoic acid (DHA). These omega-3 fats are found exclusively in seafood and marine algae.

As you can see from the chart below, it is also possible for the body to synthesize EPA and DHA from the short-chain omega-3 alpha-linolenic acid (ALA). ALA is found in plant foods such as flax, hemp and pumpkin seeds and walnuts.

Click thumbnail for a larger version

However, research clearly indicates that the conversion of ALA to EPA and DHA is extremely limited. Less than 5% of ALA gets converted to EPA, and less than 0.5% (one-half of one percent) of ALA is converted to DHA.

A common misconception, especially amongst vegetarians and vegans, is that our need for EPA and DHA can be met by consuming flax oil and other plant sources of ALA. But the conversion numbers above clearly indicate that this isn’t the case.

Studies have shown that ALA supplements (like flax oil) are unable to raise plasma DHA levels in vegans, despite low DHA levels at baseline. (ref) So unless they are supplementing with an algae-derived source of DHA, it is likely that most vegetarians and vegans are deficient.

This is significant because researchers now believe that the majority of the health benefits we get from dietary omega-3 fats come from the longer chain derivatives (especially DHA, as I will explain below).

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Is DHA essential?

In fact, some researchers have proposed that DHA is essential. When scientists label a nutrient as “essential”, they they’re not just saying that it’s “very important”. In the context of nutrition essential means that the nutrient cannot be synthesized in the human body, and must be derived from dietary sources.

According to today’s nutrition textbooks, there are only two essential fatty acids, omega-6 linoleic acid (LA) and omega-3 alpha-linolenic acid (ALA). It is believed that as long as these fats are present in the diet, all of the longer-chain omega-3 and omega-6 derivatives can be synthesized in the body.

As I pointed out above, while this is theoretically possible, in reality the conversion doesn’t work well. This is true even for healthy people, but it’s especially true for those with nutrient deficiencies, because the conversion of ALA to DHA depends on zinc, iron and pyridoxine.

The bioavailability of iron in plant sources is poor compared to animal sources, so iron deficiency is common in vegans and vegetarians. This is another reason why they tend to be poor converters of ALA to DHA.

Several other observations support the hypothesis that DHA is essential:

  • DHA content in the tissues of all mammals is very similar despite widely varying intakes of omega-3 fatty acids. 1
  • DHA and AA, but not other omega-3 or omega-6 fatty acids, are selectively transferred across the placenta (PDF).
  • 60% of the dry matter of the brain is lipid, and DHA and AA are the most abundant fatty acids of brain phospholipids (PDF)
  • DHA status in newborns is much lower in those receiving formula with LA and ALA, than in those receiving milk or formula with pre-formed DHA (PDF)

It is possible that the primarily carnivorous diet of our ancestors, which ensured a consistently high dietary intake of DHA and AA, precluded the need to evolve efficient conversion mechanisms.

In other words, since we were eating a lot of meat and fish with pre-formed DHA and AA, our bodies didn’t need to be experts at converting ALA and LA in plants to DHA and AA. It is far easier for the body to assimilate pre-formed DHA and AA than it is to synthesize them from precursors.

What about EPA? Isn’t it essential too?

EPA is another long-chain omega-3 fatty acid that is conventionally believed to be responsible for the benefits of fish consumption.

EPA is often referred to as “anti-inflammatory”. However, according to this report on essential fatty acids by Masterjohn, EPA’s effect seems to be more of an interference with the metabolism of omega-6 arachidonic acid (AA) than the performance of any essential role itself.

Take a look at the chart again that I linked to in the beginning of the post. The fatty acids in blue boxes are less inflammatory, and those in pink boxes are more inflammatory. The chart shows that AA is used to synthesize prostaglandins that cause inflammation (indicated by the pink box on the chart). Because it has the same number of carbon atoms, EPA competes with AA for the enzymes that metabolize it. Since the prostaglandins made by EPA are less inflammatory than those made by AA (indicated by the blue box), EPA is often referred to as “anti-inflammatory”.

But while EPA is certainly less inflammatory than AA, it doesn’t make sense that the body would require an essential fatty acid just to block the inflammatory effects of of another fatty acid.

By contrast, DHA is used to synthesize compounds that play an active role in resolving inflammation. EPA only makes these compounds in the presence of aspirin (PDF). EPA is thus likely to simply be a byproduct of compromised DHA synthesis.

What does this mean to you?

Putting all of this information together yields the following conclusions:

  1. DHA is the most important of the omega-3 fatty acids, and is primarily responsible for the benefits we get from consuming them.
  2. DHA is likely to be essential, which means that you must consume it in the diet to prevent disease and ensure optimal function.
  3. The conversion of plant sources of ALA, such as flax seed oil, to DHA is poor in healthy people and even worse in people deficient in certain nutrients. Vegans and vegetarians are especially prone to be poor converters of ALA to DHA.
  4. If you’ve been buying flax oil in the hopes that it will help, you’d be far better off putting that money towards some fish or fish oil capsules.
Dietary changes over the past century have lowered the DHA status to a state of subclinical deficiency in many people. Countless studies show that this deficiency is at least in part to blame for the rising incidence of cardiovascular disease, inflammatory disease, mental and psychiatric disorders and suboptimal neurodevelopment.

DHA is not the only reason to eat fish, which is also rich in selenium and vitamin D. However, DHA is likely to be the primary reason why populations that eat fish on a regular basis have consistently been shown to healthier than those that don’t. We’ll discuss this further in the next article.

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  1. Jones PJH, Kubow S. Lipids, Sterols, and their Metabolites. In: Shils ME, et al., eds. Modern Nutrition in Health and Disease: Tenth Edition. Baltimore, MD; Philadelphia, PA: Lippincott Williams & Wilkins (2006) pp. 92-122.
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Join the conversation

  1. I’m concerned about the heavy metal accumulation in our bodies from consuming as much fish and or omega 3 supplements…esp. Mercury. My blood work recently showed very high levels of Mercury. The salmon I eat is fresh caught, not farmed and I take krill oil supplements. Any thoughts? How do we avoid potentially consuming these metals?

      • Studies have shown that the larger fish that prey on smaller fish such as tuna, shark, etc. are the fish that are high in mercury, but the fishes that feeds on rich plankton shows less mercury… We had tried krill oil before but we are allergic to shrimp for some reason, so we chose Omega 3 supplement derived from fish as an alternative anti inflammatory and did works in keeping our arthritis(RA) at bay. This what we are taking now, anchovy source fish oil supplement – http://visiongroupcorp.com/omega3.html

  2. So in conclusion, eating nuts(high in omega3ALA and omega6), is a waste of money?
    -ALA conversion to DHA is poor.
    -omega6 is present everywhere(western diet)
    Personally I go fish. Not supplements.

    BTW, is there any value in ALA, apart from that poor conversion? I read it could be bad for your eyes.

    • nuts have a lot of health benefits but the polyunsaturated fats isn’t one of them.

  3. What’s the name of the algae that has the chain of Omega 3 we need? there are many algaes…I eat spirulina but I know it doesn’t have more Omega 3 than Omega 6…
    I eat fish (salmon) once a week but I dont want to need to eat it every day, there has to be another solution and it cannot be pills, we are suppose to find the natural remedies in nature, I don’t eat anything processed and that includes fish oil supplements (which btw I read it’s not beneficial at all..o course, like everything unnatural)

    • The algae with DHA in it is expensive and much lower in omega 3 than fish. There is a natural solution, it’s called eating more fish 🙂 You only need to eat three 4 ounce servings of salmon a week to get enough omega 3 as long as you aren’t cooking with vegetable oils.

    • I can appreciate your desire to have natural solutions, but not to the exclusion of all else. One should selectively take advantage of technologies that make beneficial substances available that either are not present in sufficient amounts in nature (to where the amount of food needed to be consumed is impossible to achieve) or are more pure than can be found in nature. Given that the average life span of humans in history particularly before agriculture was only 20-30 years, the age of the population now demands a different approach.

      Our ancestors had nothing but natural substances, but of course the main causes of death were trauma and infections. Anyway, having dealt with absolute garbage and some good stuff in the supplement community for over 30 years, half before the Internet, I encourage you to keep an open mind and don’t automatically eliminate supplements because they are “not natural.”

  4. chris, do you have any references for your claim that only 0.5% of ALA converts to DHA? thanks.

    • Do you need more than .5% of your ALA converted to DHA Marcus? Before we go into all the things that modern technological research claims, I think it is important to remember that if the human body converts, on a given test, only .5% of ALA to DHA, it quite possibly knows this is all it needs converted. Especially if in every person’s history, during the time in the womb, and during the first year of life, the conversion rate was far higher, because each human needed a lot of DHA deposited in their growing brain.

      Over and over you will read in articles pushing fish oil supplements, that the word “inefficient” is used to describe the conversion of ALA to DHA. After 100 years of scientific research into human physiology, the research is still ongoing, and making progress (read “we don’t know a lot yet”) but for millions of years, humans have survived and overpopulated the planet with no help from supplemental DHA. So without reading a single piece of research, I can come to the conclusion that whoever is using the word “inefficient” here is doing a sales job, not a presentation about the needs and capabilities of the human body.

      But if you do read the research, you get a very confusing picture. I suggest you read every comment above to get a somewhat balanced picture of the situation. You’ll still probably be confused. My solution in such a case is to skip the supplements and eat a large variety of the healthiest food you can find. Almost without exception, if you spend all the money you spend on supplements on getting fresher organic unprocessed foods, you will find you need very little food to flourish. But begin by reading all the ideas here. Not the questions, but the ideas.

      The whole reason people take fish oil supplements is that someone sold them the idea that they are short on the ingredients: DHA and EPA. They’ve also been sold on the idea that because the average American eats a lot of excess, ruined omega-6, that they themselves need to “balance” their diet accordingly, whether they ingest ruined omega-6 fats or not. Whether they have an imbalance or not. No logic here. Just the herding of sheep by hucksters. But the tragic result can be an overdose of a substance that (remember?) the adult human body never derives more than .5% of from the parent material. Quite scary, really.

      If you are willing to try to learn something about how important unsaturated fats are to your body, and where they are used continually to allow metabolism and immunity, and how an imbalance or a dose of ruined unsaturated fats can make you very sick, please consider reading this article:


      Unsaturated fat is not just something stored in a fat cell or transported in the blood plasma. It is critical to the very life of each cell you have. Learn how beautifully complicated, but orchestrated things are, millisecond to millisecond in a human cell, and you may not worry any more about supplements and balances, but simply just find some good food choices and feast.

      Best of health,


      • No actually glen, the fact that humans cannot convert a large amount of ALA to DHA does not indicate that humans only require a small dose of DHA for optimum health, it implies that humans evolved to get their DHA preformed from animal foods. That is why herbivores can efficiently convert nutrients like beta carotene into vitamin A while carnivores cannot. Animals which evolved to ingest the nutrients preformed generally have poor conversion rates.
        Clearly you haven’t been reading the literature because it overwhelmingly supports the contention that DHA is responsible for the vast majority of omega 3 health benefits.

        • Marcus, first, to answer your original question, I have been reading more (as you suggested I might need to), and found a somewhat believable range for the conversion rate of ALA to DHA. The following discussion suggests the range may be from .2% up to 4%:


          This article makes many other good points which I will refer to in a moment.

          For the general discussion I would mention there is more in Chris’ next article in this series regarding fish vs fish oil:


          He goes nicely into the issue. I’ll also mention another article which describes the extensive processing involved in creating omega-3 capsules from fish oil:


          Even if you just breeze through to the end, you’ll get the idea that fish are so extensively processed that to end up with a supplement that contains only DHA and EPA, the fish was broken down in many different ways (heat, acids, solvents, enzymes) to the point where even the DHA and EPA were separate. Then they were put together again in the capsule.

          I would not call this “preformed”. To me, preformed is limited to what you might get if you eat brain, or ingest raw milk. Some preformed DHA also comes from meats, cheese, etc. but we must remember that these sources also provide even more of the parent, alpha-linolenic acid (ALA) which our bodies can covert to DHA. Human, cow and goat milk is the only preformed DHA that some infants get. Ever. They don’t eat fish and they don’t eat sea plants, and few eat brains. Vegan children are definitely in this camp. And on that point I totally hang my argument that after the DHA that children get from the placenta before birth, and from nursing for a couple of years, there can be very little preformed DHA intake and yet humans seem to get by and survive.

          I admit their visual acuity and brain function may be measurably better, though not noticeably better to an observer, if they are given more DHA. But I am going to extremes here using a vegan child as an example. Yet they do grow up and advance through school in spite of the apparent odds against them. This is what leads me to believe that humans can do quite well without supplementing with DHA, if they otherwise have proper nutrition, especially that they not have their body overwhelmed with toxic, ruined omega-6 oils that compete with the enzymes for converting ALA to DHA, etc.

          I never said that DHA is not responsible for the majority of omega-3 health benefits. I agree with that. I just said that once an individual is past the age of 1 year, they need so little additional DHA and EPA that without an overload of toxic ruined omega-6 oils, and with adequate diet, they are fine for life. After reading through the first link I provided above, I’ll adjust this and say it may be more like 2 years that a child’s growing brain can use supplemental DHA if it isn’t garnered from nursing or good preformed sources.

          The normal thing in human existence before the invention of baby formula and other processed foods, was that children who nursed for a year were fully stocked up on the omega-3 derivatives of DHA and EPA, and even a vegetarian or vegan diet left them with fine mental and visual faculties. Since 2002 in the USA, and earlier in Europe, infant formulas have had DHA included.

          Stay in good health!

          • Hello Glen, I wasn’t suggesting that people should take fish oil, I think we should get our Omega 3 by eating more fish. It is true that large quantities of DHA is not essential to survival after the age of 2 but it clearly has a significant effect on health outcomes. There is no shortage of studies demonstrating that regular consumption of oily fish significantly lowers mortality rates, and it has been proven to be therapeutic for a number of conditions – http://jama.jamanetwork.com/article.aspx?articleid=203640

            I agree that most omnivores also aren’t getting enough omega 3. This is because they aren’t eating enough oily fish or pastured meat/eggs. Most omnivores are eating the SWD or Standard western diet, which is extremely unhealthy. Both vegans and SWD eaters could benefit from adding more oily fish to their diets.

      • Apart from apparently being written by evangelists christians and not resembling a credible study in any shape or form, the study you linked argues in favor of soy lecithin and choline. Not only is soy an extremely unhealthy food, but liver and egg yolks are more than ten times higher in choline than plant foods. More vegan nonsense.

        • Marcus, I think you skimmed the BodyBio article a bit too quickly. Lots of good information there. The only references there to lecithin and choline were warning of the dangers of each.

          And it mentioned that lecithin supplements are often sold as Phosphatidylcholine (PC) just because one of the components of lecithin is PC, but that they are different, and should not be confused.

          After that clarification, the article is not interested in lecithin.

          • Yes, I did skim the article, especially when I saw the reference to yeshua, that was a big red flag that it wasn’t worth my time reading. I wouldn’t use supplemental lecithin, but choline rich foods clearly have tremendous health benefits, as the article correctly points out.

  5. I’ve been taking Laminine Omega and I’m satisfied with it. The fish oil is sourced from Engraulis Ringens (a member of the anchovy family), found in the Humboldt Current off the coast of South America near Peru, where the waters are clean and clear. Phytoplankton that the Engraulis Ringens species consumes in this region is rich in DHA and EPA, giving the fish the highest naturally occurring ratios of DHA and EPA of any other fish species. The fish oil also undergoes molecular distillation, and is tested before and after the process to remove gunk and toxins and ensure the safety of the oil.

    It is patented and has the highest quality sources for Omega Fatty Acid 3 (EPA and DHA). It also has CoQ10(Extended Release), Vitamin K2… It is made in USA; head office is in California. I order it online http://tinyurl.com/q8fjc93 cuz it’s convenient and there’s free delivery & handling in the States & I think in Canada also. Delivery varies from 3 to 7 days. You may click Join if you want to be a member and get the member’s price Or click RETAIL ORDER if you don’t want to be a member and just want to buy the product.

  6. Chris, I would love to see the sources you have studied for this post. Can you share them please?

  7. For me the bigger issue is the food chain and the avoidance of mass produced farmed produce, which includes fish, livestock, etc.

    If we eat fish that no longer gets omega oils from natural sources (algae) but from produced food pellets with added omega oil supplements then what is the advantage of eating the fish? Even now, they are experimenting with producing the algae omega oils from DNA modified plants to add to fish feed as it will be cheaper.

    If we are what we eat, then it follows that our food is what it eats…if the soil/food source is empty so will be the plants and animals.

    So should we eat the fish or just take the omega oil supplements? Does the fish taking supplements still produce a better omega oil for us?

  8. What a wonderful article and thread. Chris, I have spent the last two weeks consuming your wonderful gift of thought. I thank you for that.

    This is the first thread I have seen you not answer what seems to be a very valid thought process. While I have not read anything from Brian Peskin yet, Mr. Atkisson does a noble job of describing his position. You ignore it. Why?

    Is it not possible that the formation of DHA/EPA is not as well understood as you make it out to be?

  9. This all sounds plausible – deficiency of DHA in modern diet etc – but unfortunately the problem is being approached from the wrong way around. The fact is that current levels of fishing are already unsustainable – and with the human population forecast to go on expanding there just won’t be enough fish on the planet to provide every one with fish oil (and that’s without even going into the problem of high concentrations of heavy metals and other poisonous contaminants found in these oils … or the welfare of the poor, wretched fish). The obvious common sense solution is to concentrate efforts on finding a SUSTAINABLE source of DHA from marine algae/ flax etc. In order for the planet to support our burgeoning population we should all be working towards a vegan diet. So instead of saying, “fish oil’s better than flax,” we should be saying, “where can we find efficacious alternatives to fish oil?”

    • Great post. Until people realise that the way the human population is living today is harming the planet and its inhabitants both human and animal then unfortunately the future prospects of our species does not look good.

      There already is algae derived DHA available. My question is do we really need to take these supplements to maintain health?

  10. chasWm, you are new to this discussion and I want to point out that Chris continued it in two other articles which he mentioned in his May 11, 2010 comment above. You can link to them with:
    These will bring you better up to date on Chris’s information on omega-6 and omega-3.
    Actually, Chris is fairly accurate in claiming that fish is practically the only source of of EPA/DHA in it’s pure form. You can also get DHA from eating brains.
    In contrast to all that you will read in Chris’s 3 articles on these essential oils, which stress getting the EPA/DHA in a pure state from fish oils to insure a given quantity, I tend to rely on what you mention as my sources: other foods that contain the top (or parent) level, omega-3 as alpha-linolenic acid, and omega-6 as linoleic acid. This is not just nuts, but almost every living substance. Animal products have higher percentages of all fats usually than do plants, so they also have higher percentages of the more rare omega-6 and omega-3 oils. I believe if you eat a balanced, and healthy diet of only whole foods, and no processed foods, fried foods or factory created “foods” such as trans fats, you will definitely get enough omega-6 and omega-3 in an acceptable ratio to allow your body to create all the derivatives detailed in the above chart, just as human bodies have been doing for millions of years before fish oils were invented.
    I believe from the studies I’ve read, that humans can adequately derive DHA and EPA from the parent omega-3. Chris sites studies that show that this conversion is “inefficient”. This word “inefficient” is used to because low percentages of DHA/EPA are derived from the parent. This is ignorant of the fact that parent omega-6 and omega-3 are stored by the body, and the conversion only takes place as DHA and EPA are actually needed. There is no “inefficiency”. Rather there is a designed “make what is needed”. However, it is true that if one eats heavily of processed foods containing cheap vegetable and seed oils, the enzymes needed for converting omega-3 may be derailed into converting omega-6 into it’s derivatives, as there is competition for the same enzymes. The solution though is not to consume fish oil sources of DHA/EPA to “balance” these ruined oils in a junk-food diet, but to cut out the ruined oils, fried foods, etc. and eat mostly free-range animal products that will have a healthy balance of the omega’s that will allow the conversions of the omega’s to take place, giving sufficient quantities of both omega-6 and omega-3 derivatives.
    Free-range cattle end up with a o-6:o-3 ratio of about 5:1. Wild game has a ratio of about 4:1. This 4:1 ratio is what has been proven to be ideal for functioning of the human brain:
    There are many writers who will say that humans should have a 1:1 ratio or sometimes a 2:1 ratio of omega-6:omega-3. I personally believe, after reading studies that show the ratio of wild animals, that a 4:1 ratio is more acceptable, and will be what you will get without having to measure anything or worry about it at all if you just restrict your diet to whole, natural, foods and leave off the junk. Eating a great variety of foods is also important. A diet heavy in nuts and grains will generally give you far too much omega-6. A few nuts such as walnuts and hemp seed are balanced more like a 4:1 ratio. The rest, like most grains, have far too little omega-3 to be healthy.
    Another thing I like about you emphasizing raw sources of food over using fish for getting your omega-3 chasWM, is that omega-3 is the most perishable of all the unsaturated oils. From fish sitting around on a vendor’s ice, or before being canned, you can end up with already oxidized omega-3. The DHA from this will not be good for your body. The same is even more true for fish oils processed into capsules. How will you know if fish oil capsules contain unoxidized, healthy oil? It’s a lot safer in this season to go to the store and buy a few walnuts, in the shell, break them open and consume them right away. You only need a few walnuts to give you omega-3 that will equal what you get from a couple of fish-oil capsules. And the bonus is you will also be getting fresh omega-6 to balance it!
    Best of health to you, and keep exploring and learning.

    • To Chris and Glenn, have either of you read the writings and studies conducted by Patricia Kane PhD? She promotes a 4:1 ratio of 0mega 6:3 and also discusses the benefits of phosphotidyl choline. In fact there are many studies that show reversal of neurological diseases when the 4:1 ratio is in balance. Here is the link : http://patriciakane.net. To our health, cheers!

      • Yes, Carla, I’ve read Dr. Kane. She gives great insight into what happens when someone gets their diet right by eating no ruined vegetable oils, but continues to think they will benefit from supplementing with fish oil, thus getting a physiological overdose of DHA and EPA. It’s a neurological disaster. She is on the cutting edge of research showing that a person on a healthy diet needs no polyunsaturated supplements and they can do great damage.

        The rest of the field will catch up in 10 or 15 years, hopefully. By the age of 1 or 2, all humans have almost all the DHA they need, already in their brain. Their bodies use most of their incoming alpha-linolenic acid (ALA) in a conversion to DHA and EPA. After that, unless a person has a neurological problem, most of their ingested ALA is broken down into other derivatives that are useful to the immune system.

        Thanks for pointing out the work of Patricia Kane.

  11. One can also get their fill of EPA/DHA from seeds, such as chia seeds and hemp seeds which are better used by the body than processed fish oil and contain vitamins, mineral and soluable fiber. I am sure that there are other seeds with fulfill EPA/DHA requirements other than Fish. I dont believe that fish is the only source of EPA/DHA as was stated in earlier articles

  12. Great article Chris,

    Thanks for all your help. You are one of my go to sources for of all my nutritional inquiries/questions. I had a quick follow-up that I would greatly appreciate if you had any insight. What is the conversion of LA to AA. Is it 100% or do you have a number?

    Or else it would seem that consuming flax would worsen or ratio if all if LA was converted at a better ratio and ALA wasn’t converted to DHA more than a very little.


  13. So, I know this article is really old, but I thought it would be relevant to share this study which conflicts with your assertion that vegans & lacto-ovo-vegetarians are poor converters of ALA to EPA/DHA. When their levels were measured, non-fish-eaters appeared to have a far superior conversion ability to fish-eaters (presumably because the body increases conversion in the absence of dietary sources of EPA/DHA – similar to the mechanism for Iron absorption). Which is lucky for the millions of people with fish allergies…


  14. There are soooooo many other foods out there that have omega 3–in general–to be concerned with salmon.

    Also, there are plenty of people and many cultures who do not eat fish, and they are just as healthy.

    And, our body does not need a lot of omega 3. In fact, our body releases omega 3 when needed.

    Fish, salmon, is highly overrated.

    I’d like to know when this salmon thing got started, anyway.

    Maybe the supplement companies got it gong with fish oi, and then the food companies followed it with “eat more fish!!”

      • Chris,
        Thanks for including references. I’m currently in a Nutrition course for my Masters in Sport and Health Science. It’s a good program, and this class is OK, but the first two chapters of the book are dedicated to advertising for MyPlate.gov and using the NutriCalc+ program to make sure we’re constructing all-inclusive diets of grain and dairy and not too much protein. The book actually states that its goal is to promote a vegetarian or semi-vegetarian diet. Your blogs have been an arsenal of counter-information that have helped me personally as well as academically to present information from an educated perspective.


  15. I have never posted a comment before, but you make it very easy. I looked at the fatty acid composition table just today. I congratulated myself that I had a can of sardines and one of mackerel on the shelf. I just threw them out. The mackerel with its advertised omega three content was packed in sunflower oil. The sardines were packed in oil (soybean).

  16. Hi Chris, Waiting to hear your opinion of the damning evidence against fish oil supplementation presented by Brian Peskin. I have a couple thoughts, but would like to hear yours first. Thank you!!

    • Are you allergic to marine algae? That’s a vegan/vegetarian source of DHA.

      • That isn’t part of the regular allergy panel, they only test you on various species of fish and crustacean here in Canada.