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Omega 3 questions

  1. Nov 18, 2009 #1
    I hope I have chosen the proper forum for this question, if not please accept my apologies and move to the appropiate place. Now for my question.
    I have recently started to take a little flaxseed oil to up my omega 3 intake, and have noticed that it tastes very fishy. My question is since vegetable omega 3's taste fishy, is it the omega 3's in fish that give it its fishy taste? Is it the oxidation(rancidification?) of the omega 3's in the fish that causes it to get a stronger and stronger fishy taste as it is stored?
  2. jcsd
  3. Nov 18, 2009 #2
    The omega 3's present in fish, DHA and EPA, are not present in plant based sources. Fish oil tastes like fish because it is the oil pressed from the fish. Oxidation makes the oil taste very fishy and does not provide as much nutritional benefit. Fish oil should taste basically like fresh fish.

    On a side note, since flax seed oil does not provide DHA or EPA, it is not a very good source of omega 3's. DHA has been found to be the most scientifically important so far. High concentrations of DHA are found in the brain and eyes. It is believed that the omega 3's in flax seed oil are converted to DHA and EPA within the body, but realistically the conversion rate is almost non-existent. Fatty fish are the only source of DHA and EPA omega 3's.
  4. Nov 18, 2009 #3
    there is one vegetarian source of DHA, sea algae. cost per gram will be a lot higher, but it is sufficient for w-3 if you are so inclined because DHA converts fairly well to EPA.

    another source of the ALA in flax would be walnuts.
  5. Nov 18, 2009 #4
    You're right. I forgot to mention algae. It is believed that algae is the reason that fish have such high concentrations of DHA.
  6. Nov 19, 2009 #5
    I didnt realize that there is that many different kinds of omega 3's, I thought that dha and epa were all, guess I should of checked wiki first. I'm not looking to replace my meat source omega's since I love sushi, but I noticed after taking some flax oil that my burps were fishy tasting and I have noticed that mackeral tastes a lot fishier than salmon which has about half the omega 3's and catfish isnt hardly fishy tasting at all and has very little omega 3's, it just got me wondering if there was a connection. Does ALA have any beneficial propeties or is it just a fat we dont need too much of?
  7. Nov 25, 2009 #6
    I believe the evidence is fairly inconclusive. ALA definitely has some benefit but it doesn't seem to be known exactly how or why.
    Last edited: Nov 25, 2009
  8. Nov 25, 2009 #7


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    This rather begs the question of why you think you need a supplement at all if you are getting an adequate amount of fish in your diet and enjoy it?
  9. Nov 25, 2009 #8
    It is true that I love sushi, however I live in a rural area in the southwestern desert and the closest sushi is 100 miles away so I dont get it that often, maybe once a month or so. The main reason is I recently came across an article about the budwig protocol. I have a problem with trying lots of things to see what happens, I am my own guinea pig. It supposedly helps your cells pull more oxygen into them according to the article. I was also interested in their claims that by mixing a sulfurated protein(cottage cheese) with an oil(flax) it makes a water soluble paste, to my surprise the mixture was water soluble. The first day I tried it it was terribly fishy tasting which caused me to ask my original post, however I have since found out that my flax oil was rancid and that was where the taste was coming from. My new supply is slighty nutty but there is no trace of fishiness. One other reason is the western diet is high in omega 6's and low in omega 3's, I figure any way I can get the ratio a little less lopsided would help. Is there a danger to getting to many omega 3's?
  10. Nov 25, 2009 #9

    jim mcnamara

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    Breakdown of trimethylamine oxide occurs in dead fish tissues. It breaks down into trimethylamine which at low concentrations is the 'fishy' odor people think of.

    Why it would be in flaxseed oil, I don't know. Google on 'TMAO flaxseed oil' doesn't reveal much.
  11. Nov 25, 2009 #10
    fish oil can thin the blood, so your surgeon needs to know should you be going in for repair, but i'm not aware of how you'd OD on fish oil. maybe if you're a post-menopausal woman, you might be concerned about getting too much vitamin A from cod liver oil, but most people just don't bother with the 15ml/day that is sometimes taken for arthritic inflammation.
  12. Nov 29, 2009 #11
    Postgrad Med. 2009 Nov;121(6):148-57.
    Understanding omega-3 polyunsaturated Fatty acids.

    Calder PC, Yaqoob P.

    Institute of Human Nutrition School of Medicine, Southampton General Hospital, Southampton, UK. pcc@soton.ac.uk.

    Current intakes of very long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are low in most individuals living in Western countries. A good natural source of these fatty acids is seafood, especially oily fish. Fish oil capsules contain these fatty acids also. Very long-chain omega-3 fatty acids are readily incorporated from capsules into transport (blood lipids), functional (cell and tissue), and storage (adipose) pools. This incorporation is dose-dependent and follows a kinetic pattern that is characteristic for each pool. At sufficient levels of incorporation, EPA and DHA influence the physical nature of cell membranes and membrane protein-mediated responses, lipid-mediator generation, cell signaling, and gene expression in many different cell types. Through these mechanisms, EPA and DHA influence cell and tissue physiology and the way cells and tissues respond to external signals. In most cases the effects seen are compatible with improvements in disease biomarker profiles or health-related outcomes. As a result, very long-chain omega-3 fatty acids play a role in achieving optimal health and in protection against disease. Long-chain omega-3 fatty acids not only protect against cardiovascular morbidity but also against mortality. In some conditions, for example rheumatoid arthritis, they may be beneficial as therapeutic agents. On the basis of the recognized health improvements brought about by long-chain omega-3 fatty acids, recommendations have been made to increase their intake. The plant omega-3 fatty acid, alpha-linolenic acid (ALA), can be converted to EPA, but conversion to DHA appears to be poor in humans. Effects of ALA on human health-related outcomes appear to be due to conversion to EPA, and since this is limited, moderately increased consumption of ALA may be of little benefit in improving health outcomes compared with increased intake of preformed EPA + DHA.
  13. Nov 29, 2009 #12
    The only health risk I've heard of is thinning the blood. That's only a concern when you're taking a really high dose. I read somewhere about this guy who was part of an experiment taking like five times the recommended dosage. I can't verify the accuracy or validity of the experiment, but the guy was taking the high dosages for over 3 months without any negative symptoms.

    I have also been testing fish oil on myself. This is why I have researched it. I am currently taking around 2 grams a day without any negative side effects.
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