Krill Oil 2012

July 6, 2012 Written by JP    [Font too small?]

One of the most popular columns I’ve written thus far focused on the promise of krill oil for conditions as diverse as arthritis to premenopausal syndrome. I based the content of that particular piece on several studies from the last decade that found decidedly positive results alongside an enviable safety profile. In essence, I concluded that krill oil may very well be superior to fish oil and other sources of omega 3 fatty acids. If this is indeed the case, it’s likely because of krill oils unique composition – which features astaxanthin, a potent antioxidant, and phosholipids which assist with the absorption and retention of omega 3 fatty acids and may impart health benefits of their own. However, I also cautioned that the data on krill oil was preliminary and nowhere near as extensive as that of fish oil.

Three years have passed since I posted my original krill oil (KO) assessment. Since then, numerous animal studies have been published which tend to support my initial optimism about this shellfish-derived supplement. The trials in question indicate that adding krill oil to the diets of test animals may: a) decrease the risk of “diet-induced obesity” and related liver damage; b) attenuate some of the harm caused by myocardial infarctions (heart attacks); c) reduce inflammation, oxidative stress and tissue damage in a rat-model of ulcerative colitis – a prevalent form of inflammatory bowel disease (IBD); d) protect against rheumatoid arthritis advancement and symptomatic severity. Interestingly, the one negative study I discovered examined the relative bioavailability of krill oil vs. other omega 3 sources, mostly fish oils – menhaden oil (MO), salmon (SO) or tuna (TO). According to the authors of the trial, “Rats fed KO had significantly lower DHA digestibility and brain DHA incorporation than SO and TO-fed rats. Of the n-3 PUFA sources, rats fed SO and TO had the highest n-3 PUFAs digestibility and, in turn, tissue accretion”.

Recent trials evaluating the bioavailability of krill oil (vs. fish oil) in humans have yielded positive, albeit, modest results. In general, krill oil appears to provide comparable effects to fish oil using a slightly lower dosage. In real world terms, 543 mg of DHA & EPA from krill oil has been found equivalent to 864 mg of DHA & EPA from fish oil. However, taking into account the considerably higher cost of krill oil, this isn’t a very good proposal. In addition, one experiment, which tested these very same amounts of fish and krill oil over a 7 week period found, “no statistically significant changes in any of the serum lipids or markers of oxidative stress or inflammation between the study groups”. That’s a clear disappointment and in stark contrast to the evidence I presented in my initial column. In fact, the last few years have failed to produce any human data that inspires much confidence in the use of krill oil over other omega 3 sources. In fairness, there may be confounding factors involved. For instance, the majority of the recent studies have used a source of krill oil manufactured by Aker Biomarine which contains low levels of astaxanthin – significantly lower than the amount contained in the krill oil used in some of the earlier investigations. But, what interests me most is this: Krill oil sales have skyrocketed over the past few years although the quality of research supporting its use has taken a turn for the worse. Only time will tell if continued brisk sales and better study results are in the cards for krill oil in the years to come. At the moment, my personal view of KO is not nearly as rosy as it was in 2009.

Note: Please check out the “Comments & Updates” section of this blog – at the bottom of the page. You can find the latest research about this topic there!

To learn more about the studies referenced in today’s column, please click on the following links:

Study 1 – Beneficial Effects by Intake of Euphausiacea Pacifica on High-Fat (link)

Study 2 – A Krill Oil Supplemented Diet Suppresses Hepatic Steatosis in High (link)

Study 3 – Differential Effects of Krill Oil & Fish Oil on the Hepatic Transcriptome(link)

Study 4 – Krill Oil Attenuates Left Ventricular Dilatation After Myocardial (link)

Study 5 – Dietary Supplementation of Krill Oil Attenuates Inflammation and (link)

Study 6 – Supplementation of Diet with Krill Oil Protects Against Experimental (link)

Study 7 – Different Sources of Omega-3 Polyunsaturated Fatty Acids Affects (link)

Study 8 – Incorporation of EPA and DHA Into Plasma Phospholipids in Response to (link)

Study 9 – Metabolic Effects of Krill Oil are Essentially Similar to Those of Fish Oil (link)

Study 10 – Krill Oil Significantly Decreases 2-Arachidonoylglycerol Plasma Levels (link)

Krill Oil Is More Bioavailable Than Conventional Fish Oil

Source: Lipids Health Dis. 2011 Aug 22;10:145. (link)

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Posted in Bone and Joint Health, Heart Health, Nutritional Supplements

32 Comments & Updates to “Krill Oil 2012”

  1. Orna Izakson, ND, RH (AHG) Says:

    I’ve wondered a lot about krill oil, including whether the astaxanthin levels in much of what’s commercially available is actually significant enough to do anything beyond protect the oil itself from rancidity. I did a personal trial with one bottle of krill oil; not a great test, I know. I wasn’t thrilled with the taste (caps, which I kept in the freezer), and didn’t feel I got as much from them as from my super concentrated fish oil. These findings support my thoughts, especially when comparing bang to buck.

    Thanks again for your great work, JP!

  2. JP Says:

    Hi Orna,

    Thank you for sharing your experience with krill oil. A client of mine does the exact same thing – freezes krill oil soft gels prior to taking them. According to her, this helps minimize any “fishy burps” or GI upset.

    I think astaxanthin content is certainly part of the equation. In the recent past, I unexpectedly learned a considerable amount about the krill oil scene – marketing, production, research and development, etc. I even researched strategies to improve the composition of krill oil supplements myself. Unfortunately, it seems as though most krill oil suppliers aren’t all that interested in improving their products or verifying the claims that help spur the sale of their products. This is understandable from a business standpoint. That’s about all I should say about that. 😉

    Be well!


  3. rob Says:

    Good follow up.

    I found the same thing you did. At first Krill Oil seemed to good to be true and as it stands now it is. Its still a good fish oil supplement but the cost doesnt justify it being added to ones daily routine IMO, you can get top quality fish oil and combine it with an astaanxthin supplement( which may be another over hyped supp).

  4. JP Says:

    Thank you, Rob.

    Interestingly, I think the research on astaxanthin is stronger than it’s ever been. IMO, it’s been pretty consistent and positive. But, as Orna pointed out (above), the amount of astaxanthin contained in most krill oil supplements is unlikely to be enough to provoke a therapeutic effect. Then there’s the phospholipid issue. Once again, I think there’s value there. However, just how cost effective and valuable a factor the phospholipids present hasn’t been well established.

    Be well!


  5. Orna Izakson, ND, RH (AHG) Says:

    Well, that was certainly provocative, JP! Now, of course, I really want the inside dirt. You should tease newspaper reporters (even in retirement) that way. 🙂


  6. Cloudy Says:

    Hey JP, i would like to know about Dr. Mercola’s krill oil, because i’ve seen a lot of divergence about it on the comments of another topic of krill oil that you’ve made a few years ago.
    Can you tell me what you think about it, if it’s high quality?
    Thanks a lot!

  7. JP Says:

    Hi Cloudy,

    It wouldn’t be among my top choices. The DHA and EPA levels aren’t great nor is the astaxanthin concentration anywhere near optimal. In my opinion, this is an outdated product that is unlikely to do much good for most people – especially if used at the recommended dosage.

    Be well!


  8. Larry Says:

    I just stumbled across your website and it is now bookmarked! Great information. Have to admit that I bought into Mercola’s hype and used his krill oil for a period of time before switching to something more affordable. Prior to that, we used fish oil…specifically nordic naturals. After reviewing your information along with the excellent comments, I am going to make the switch back to fish oil for my family. JP…it sounds like you are not big on recommended products but was curious to see if anyone else would recommend an affordable quality fish oil supplement? I did see the review for Coromega on your website so am thinking about giving that a go. Again…great website/info JP. Look forward to following.

  9. Larry Says:

    OK…back already. Did some research on Coromega and it appears that there are concerns about it containing sodium benzoate along with vit c which can produce benzene. Thoughts anyone?

    May go with Barlean’s (combined with an astaxanthin supplement). Seems to be a pretty solid liquid fish oil.

  10. JP Says:

    Thank you, Larry.

    Vitacost makes a pure, reliable fish oil supplement that’s quite affordable:

    Personally, I’m not concerned about the minute amount of sodium benzoate and any potential interaction with Vitamin C. However, if you’d prefer using an emulsified fish oil product that omits these ingredients, Barlean’s Omega Swirl product line is a good option.

    I think combining emulsified fish oil with astaxanthin is a good idea. I’d take them at the same time – at the middle or end of a meal.

    Be well and happy holidays!


  11. BG Says:

    Thanks JP – very helpful information.

    My cautious approach to using fish oil (rather than krill from “pristine Antarctic waters”) stems from what I have read about mercury and other toxic contamination of fish typically sourced for supplement oil extraction.

    Any thoughts on that will be appreciated.


  12. JP Says:

    Thank you, Brian.

    Many brands of fish oil are purified via molecular distillation. The end result is an omega-3 extract that is virtually devoid of mercury, other heavy metals and various toxins (dioxins, etc.). Recently, Consumer Lab published the results of their testing which demonstrated that many popular brands of fish oil were indeed safe in this regard. The same is true of their test results for several krill oil products. Unfortunately, I’m not permitted to list the various brands.

    IMO, any reputable brand that sells distilled/purified fish oil is unlikely to present a problem re: contamination, mercury, etc.

    Be well!


  13. BG Says:

    Thanks JP

    I was unaware of the fish purification process and a search took me to this site comparing molecular distillation with oil refining

    My starting point with nutrition is to seek the closest possible to the way Nature intended. The advantages and disadvantages mention by Biovea pose questions of compromise. I imagine processing of oil from fish or krill ‘denatures’ the product to some degree. But it seems krill oil has fewer additional ingredients to ‘mess up Nature’s formula’ than fish oils I have seen.

    The loss of “natural tryglicerides” is classed as a disadvantage but isn’t lowering trigliceride levels supposed to be a good thing?

    Having started out buying Superba/Aker Biomarine krill oil on the strength of a Dr Mercola recommendation … but needed a UK source so I haven’t used his formulation (which doesn’t impress you) … I recently discovered how little astaxanthin is present in the Superba oil I have been taking for months. Trying to get supplementation right makes you lose the will to live!

    Going back to square one I would like to know the correct astaxanthin daily dose for good therapeutic effectiveness. If it really is from 4 to 12mg, then Superba krill oil delivers only 2.5 to 8%. The next question is: why don’t 500mg krill oil capsules provide 4mg of astaxanthin? Is it to do with processing? If a krill sourced astaxanthin capsule contains 4mg, is some kind of concentrated extraction method used – and does this lose something of Nature’s intended ingredient ‘balance’.

    Forgive all the questions, but having read that astaxanthin is one of the top three supplements above all others (according to Dr M) I’m probably not alone in wanting to be clear about the best form to take for regular health maintenance. Or is a good mix of organic food without supplementation still the best recipe – even for the elderly? Because of bio-availability doubts among others, mainstream thinking seems to suggest supplementation is a waste of time and money and can be harmful. Some of the fillers and other non-therapeutic ingredients to make supplement manufacture easier clouds the picture.

    Live long and prosper


  14. JP Says:

    Hi Brian,

    I’ll attempt to address each of your questions. If I miss anything, please let me know.

    1) Having high triglycerides in the blood is largely considered a risk factor for cardiovascular disease. But, fish oil that is rich in the triglyceride form of DHA & EPA, generally tends to lower triglycerides in humans.

    2) In terms of astaxanthin dosage, I’d say a general therapeutic dosage is between 4 to 12 mg daily. Some studies have used higher dosages and report efficacy and safety as well.

    3) Why don’t all krill oils contain a therapeutic dosage of astaxanthin? One reason is due to cost. Also, krill contains relatively small and variable amounts of naturally occurring astaxanthin. Superba krill oil claims to provide astanxathin exclusively derived from krill. Other krill oils, such as Azantis and Neptune, add algae-derived astaxanthin to increase the astaxanthin content of their products. Incidentally, astaxanthin products are almost always sourced from algae – which is much more cost effective and eco-friendly.

    4) I almost always recommend a low glycemic, whole food based diet as a foundation. I use and recommend supplements based on individual needs. This almost always includes a multi-nutrient formula at a bare minimum. As for omega-3 supplementation, it largely depends on how much fish and other omega-3 foods are a part of ones daily diet. Finally, the more disciplined one is with their diet (and lifestyle), the fewer supplements they require.

    Here are some general supplement recommendations that I’ve put together for those who haven’t worked with me individually:

    Be well!


  15. Serge Says:

    Hi JP,

    I’ve been a lurker here for some time, initially drawn to the astonishing depth of information available on your original Krill posting and associated comments list (I think I’ve actually read the lot!), and a regular reader of your posts via RSS. So a hearty thanks for the site and the information.

    So now I have a chance to contribute in some small way by bringing your attention to this recent research article, “Enhanced cognitive function and antidepressant-like effects after krill oil supplementation in rats”, available here:

    It’s open access so anyone can read it and I’ll add that the study was partially funded by Aker.

    As a KO consumer (currently taking Jedwards Virgin Krill Oil 500mg), and no doubt suffering a healthy dose of confirmation bias, I’m particularly interested in the study’s apparent indirect affirmation of a difference in FO/KO absorption (the study doesn’t directly compare FO/KO, which is a shame, but refers to other studies which do). I again, however, refer to the funding.

    For the record, I’m in no way affiliated with any company or any particular product. I am a KO consumer (currently taking Jedwards Virgin Krill Oil 500mg) in good health, simply interested in getting a good, high dose of EFAs.

    I’m aware of your current, and understandable, stance on KO but I, and no doubt many others, would be interested in any thoughts you had on the study.



  16. JP Says:

    Hi Serge,

    Thanks a lot for adding your comments to the mix. I appreciate it.

    I actually stumbled upon the very same study this past weekend. I think it’s an encouraging finding. However, it is an animal study and may not translate to humans. At this point in the krill oil “game”, I think human-based studies should move to the forefront. IMO, even a small, pilot study involving adult men and women would be much more meaningful.

    In terms of the absorption issue, I don’t place a lot of stock in the recent studies that have found modestly enhanced bioavailability of krill oil vs. fish oil. In practical terms, simply taking a slightly higher amount of omega-3s from fish oil should handily compensate for any difference in absorption.

    Having said all of this, I believe it’s unlikely that Aker is manipulating the results of their studies. Why? Most of their published research just isn’t that impressive – the findings at least. Also, my past dealings with their reps suggests that they genuinely care about their ethical standing in the nutraceutical/omega-3 community.

    Be well!


  17. Scott Says:

    Hi Larry, this is a great blog and I’m glad I found it. I’ve rarely used any form of suppliment, but I have some friends recommending nutrasea. Can you share your thoughts on this brand? Much appreciated!

  18. Scott Says:

    I’m so sorry! I was reading while I typed and put the wrong name in my post. Sorry JP! (and Larry, whoever you are)

  19. JP Says:

    Hi Scott,

    No worries!

    I don’t have any personal experience with Ascenta/NutraSea. I checked to see if they’ve been analyzed by ConsumerLab. Unfortunately, they haven’t been reviewed yet. I also visited their website. The products seem to be formulated quite well. And, if their claims about quality hold true, then I would feel comfortable using their product line.

    Be well!

    JP / Larry

  20. JP Says:

    A positive development on the krill oil front:

    Study: Krill Oil Benefits Senior Cognitive Function

    Be well!


  21. mary Says:

    hi,i read all comments about krill oil but i am really confused yet.i want to start a krill oil supplement, because i dont eat fish, but i dont know which brand has the best krill.i understand that a pure krill oil has low level of DHA,EPA and astaxathin and a blend of krill and fish oil has higher level of the it true?however i dont have understand if it is better to take a pure or a blend krill.for istance, the 2 brand that i am about to start is dr mercola krill, which is pure with low level of epa,dha and astaxantin and natural dynamix krill by azantis,which has high level of epa,dha and astaxanthin and for that reason i supposed that this is a blend krill.i dont have have important health issues except from ,i want to start krill oil because i dont eat fish and for my pcos (acne, hair loss etc).what supplement do you think is suitable for me?and finally,it is better to use a pure or a blend krill?thank you very much for the information

  22. JP Says:

    Hi Mary,

    The answer to your first question re: pure krill vs. fish/krill blends is ‘yes’. The blends typically contain higher levels of DHA, EPA and (added) astaxanthin derived from an algae source.

    It’s become more and more difficult to recommend krill oil products lately due to disappointing, inconsistent and/or lack of research from the past few years. Having said that, I still think there’s value to be found in krill oil.

    To make a long story short, I would probably opt for the Azantis blend – preferably distributed by a reputable company such as Source Naturals (their Arctic Pure product). Or, if you can afford it, you might consider a krill oil blend with added astaxanthin. One example of such a product is Asta-Krill 8 by Olympian Labs.

    Be well!


  23. mary Says:

    thank for your answer, you believe that a blend krill oil is better than a pure krill oil, do you?or more effective?i want to ask you about the ingredients of Source Naturals, Arctic Pure, Krill Oil.its ok?because i dont know anything about medium chain triglycerides, d-alpha tocopherol and soy.furthermore, the suggested use is 2 softgels daily with the first meal for 30 days, then 1 softgel daily thereafter.why we should take 1 softgel after 1 month of use?it will be wrong to continue take 2 softgels?sorry for so many questions but i have no idea and i am trying to do the best.finally, i want to combine the krill oil with an evening primrose oil supplement such as Barlean’s, Evening Primrose Oil, 1300 you believe that i will have a problem for this combination?thank you so much for your help

  24. mary Says:

    i look more carefully the source naturals arctic pure and i realize that it has many preservatives and i guess that it is not i-herb site the expiration date of this krill is 2017.could you tell me the results of consumer lab test?it has shown that it is fresh?

  25. JP Says:

    Hi Mary,

    Yes, I prefer the overall composition of the blends (higher in omega-3s and astaxanthin) to the pure krill oil.

    I’ll try to briefly address your questions about additives in the Source Naturals product and other similar products.

    Gelatin, glycerin and purified water are used in the production of the soft gel capsules that house the krill oil. Medium chain trilycerides are typically derived from coconut oil. D-alpha tocopherol is a natural form of vitamin E that is employed as a preservative. The lemon oil is primarily included as natural flavoring agent – to mask the fishy odor of krill.

    In terms of dosage, I think a fine, general dosage is 1,000 mg daily. Some people may respond to lower dosages, others may require a higher quantity. There are many variables which factor into this: body weight, reason for use, severity of symptoms, etc.

    Generally speaking, I wouldn’t anticipate any problem combining evening primrose oil and krill oil. There may be some instances where it’s inappropriate. For instance, when such supplements are combined with medications that “thin” the blood.

    In my experience, IHerb tends to stock fresh products because of their quick turnaround … things rarely stay in the warehouse for long periods of time.

    Lastly, I can’t specifically comment on Consumer Lab test results. I’ve been admonished for doing that in the past. What I can say is, as a CL customer, I would feel comfortable recommending and using the Source Naturals’ krill oil.

    Be well!


  26. JP Says:

    This study pretty much says it all (for the time being). The amount of omega-3s matter most. In effect, lower dose krill oil doesn’t measure up to higher dose fish oil.

    Be well!


  27. JP Says:

    Update 05/31/15:

    Am J Clin Nutr. 2015 May 27.

    Supplementation with a blend of krill and salmon oil is associated with increased metabolic risk in overweight men.

    BACKGROUND: Krill is an increasingly popular source of marine n-3 (ω-3) PUFA that is seen as a premium product. However, to our knowledge, the effect of krill-oil supplementation on insulin sensitivity in humans has not been reported.

    OBJECTIVE: We assessed whether supplementation with a blend of krill and salmon (KS) oil [which is rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] affects insulin sensitivity in overweight men.

    DESIGN: The design was a randomized, double-blind, controlled crossover trial. A total of 47 men with a mean ± SD age of 46.5 ± 5.1 y, who were overweight [body mass index (in kg/m2) from 25 to 30] but otherwise healthy, received 5 1-g capsules of KS oil or a control (canola oil) for 8 wk and crossed over to another treatment after a 8-wk washout period. The primary outcome was insulin sensitivity assessed by using the Matsuda method from an oral-glucose-tolerance test. Secondary outcomes included lipid profiles, inflammatory markers, 24-h ambulatory blood pressure, and carotid artery intimamedia thickness.

    RESULTS: Unexpectedly, insulin sensitivity (per the Matsuda index) was 14% lower with the KS oil than with the control oil (P = 0.049). A mediation analysis showed that, after controlling for the likely positive effects of blood EPA and DHA (i.e., the omega-3 index), the reduction in insulin sensitivity after KS-oil supplementation was more marked [27% lower than with the control oil (P = 0.009)].

    CONCLUSIONS: Supplementation with a blend of KS oil is associated with decreased insulin sensitivity. Thus, krill-oil supplementation in overweight adults could exacerbate risk of diabetes and cardiovascular disease.

    Be well!


  28. JP Says:

    Updated 11/06/15:

    Lipids Health Dis. 2015 Nov 4;14(1):142.

    Supplementation of krill oil with high phospholipid content increases sum of EPA and DHA in erythrocytes compared with low phospholipid krill oil.

    BACKGROUND: Bioavailability of krill oil has been suggested to be higher than fish oil as much of the EPA and DHA in krill oil are bound to phospholipids (PL). Hence, PL content in krill oil might play an important role in incorporation of n-3 PUFA into the RBC, conferring properties that render it effective in reducing cardiovascular disease (CVD) risk. The objective of the present trial was to test the effect of different amounts of PL in krill oil on the bioavailability of EPA and DHA, assessed as the rate of increase of n-3 PUFA in plasma and RBC, in healthy volunteers.

    METHODS AND DESIGN: In a semi randomized crossover single blind design study, 20 healthy participants consumed various oils consisting of 1.5 g/day of low PL krill oil (LPL), 3 g/day of high PL krill oil (HPL) or 3 g/day of a placebo, corn oil, for 4 weeks each separated by 8 week washout periods. Both LPL and HPL delivered 600 mg of total n-3 PUFA/day along with 600 and 1200 mg/day of PL, respectively.

    RESULTS: Changes in plasma EPA, DPA, DHA, total n-3 PUFA, n-6:n-3 ratio and EPA + DHA concentrations between LPL and HPL krill oil supplementations were observed to be similar. Intake of both forms of krill oils increased the RBC level of EPA (p < 0.001) along with reduced n-6 PUFA (LPL: p < 0.001: HPL: p = 0.007) compared to control. HPL consumption increased (p < 0.001) RBC concentrations of EPA, DPA, total and n-3 PUFA compared with LPL. Furthermore, although LPL did not alter RBC n-6:n-3 ratio or the sum of EPA and DHA compared to control, HPL intake decreased (p < 0.001) n-6:n-3 ratio relative to control with elevated (p < 0.001) sum of EPA and DHA compared to control as well as to LPL krill oil consumption. HPL krill oil intake elevated (p < 0.005) plasma total and LDL cholesterol concentrations compared to control, while LPL krill oil did not alter total and LDL cholesterol, relative to control. CONCLUSIONS: The results indicate that krill oil with higher PL levels could lead to enhanced bioavailability of n-3 PUFA compared to krill oil with lower PL levels. Be well! JP

  29. JP Says:

    Updated 12/15/15:

    Lipids in Health and Disease 2015, 14:163

    Krill oil reduces plasma triacylglycerol level and improves related lipoprotein particle concentration, fatty acid composition and redox status in healthy young adults – a pilot study

    Background: Lipid abnormalities, enhanced inflammation and oxidative stress seem to represent a vicious circle in atherogenesis, and therapeutic options directed against these processes seems like a reasonable approach in the management of atherosclerotic disorders. Krill oil (RIMFROST Sublime®) is a phospholipid-rich oil with eicosapentaenoic acid (EPA): docosahexaenoic acid (DHA) ratio of 1.8:1. In this pilot study we determined if krill oil could favourable affect plasma lipid parameters and parameters involved in the initiation and progression of atherosclerosis.

    Methods: The study was conducted as a 28 days intervention study examining effect-parameters of dietary supplementation with krill oil (832.5 mg EPA and DHA per day). 17 healthy volunteers in the age group 18–36 (mean age 23 ± 4 years) participated. Plasma lipids, lipoprotein particle sizes, fatty acid composition in plasma and red blood cells (RBCs), plasma cytokines, antioxidant capacity, acylcarntines, carnitine, choline, betaine, and trimethylamine-N-oxide (TMAO) were measured before and after supplementation.

    Results: Plasma triacylglycerol (TAG) and large very-low density lipoprotein (VLDL) & chylomicron particle concentrations decreased after 28 days of krill oil intake. A significant reduction in the TAG/HDL cholesterol resulted. Krill oil supplementation decreased n-6/n-3 polyunsaturated fatty acids (PUFA) ratio both in plasma and RBCs. This was due to increased EPA, DHA and docosapentaenoic acid (DPA) and reduced amount of arachidonic acid (AA). The increase of n-3 fatty acids and wt % of EPA and DHA in RBC was of smaller magnitude than found in plasma. Krill oil intake increased the antioxidant capacity, double bond index (DBI) and the fatty acid anti-inflammatory index. The plasma atherogenicity index remained constant whereas the thrombogenicity index decreased. Plasma choline, betaine and the carnitine precursor, γ-butyrobetaine were increased after krill oil supplementation whereas the TMAO and carnitine concentrations remained unchanged.

    Conclusion: Krill oil consumption is considered health beneficial as it decreases cardiovascular disease risk parameters through effects on plasma TAGs, lipoprotein particles, fatty acid profile, redox status and possible inflammation. Noteworthy, no adverse effects on plasma levels of TMAO and carnitine were found.

    Be well!


  30. JP Says:

    Updated 06/13/16:

    Arch Med Sci. 2016 Jun 1;12(3):507-12.

    Lipid-lowering and anti-inflammatory effects of omega 3 ethyl esters and krill oil: a randomized, cross-over, clinical trial.

    INTRODUCTION: Polyunsaturated fatty acids (PUFAs) derived from different sources could have different lipid-lowering effects in humans. The main aim of our study was to compare the short-term triglyceride-lowering efficacy of krill oil and purified omega 3 ethyl ester PUFAs in mildly overweight hypertriglyceridemic subjects.

    MATERIAL AND METHODS: This double-blind, randomized clinical trial was carried out in 25 moderately hypertriglyceridemic subjects (TG = 150-500 mg/dl). After a 4-week run-in, participants were allocated to treatment with similar pills containing omega 3 ethyl ester PUFAs 1000 mg twice a day vs. krill oil 500 mg twice a day. After 4 weeks of treatment, participants were asked to observe a 4-week wash-out period, and they were then assigned to the alternative treatment for a further period of 4 weeks.

    RESULTS: Although both PUFA sources were able to improve TG plasma levels, esterified omega 3 PUFAs were more efficacious than krill oil (p < 0.05). Nonetheless, only krill oil treatment was able to significantly improve high-density lipoprotein cholesterol and apolipoprotein AI levels, compared to both baseline (p < 0.05) and end of treatment with esterified omega 3 PUFAs (p < 0.05) values. Both treatments were able to significantly reduce high-sensitivity C-reactive protein (hs-CRP) levels from the baseline (p < 0.05), but krill oil improved it more efficaciously than esterified omega 3 PUFAs (p < 0.05). CONCLUSIONS: Krill oil has lipid-lowering effects comparable with those obtained through a 4-fold higher dose of purified omega 3 ethyl ester PUFAs in mildly overweight hypertriglyceridemic subjects, while more efficaciously reducing hs-CRP. Be well! JP

  31. JP Says:

    Note: The krill oil used in this study is manufactured by Aker and is sold by the trade name, Superba.

    Updated 10/26/16:

    PLoS One. 2016 Oct 4;11(10):e0162769.

    Krill Oil Improves Mild Knee Joint Pain: A Randomized Control Trial.

    BACKGROUND: Krill oil is an edible oil extracted from krill, a small red-colored crustacean found in the Antarctic Ocean. The administration of krill oil is reported to mitigate inflammation in patients with cardiac disease, rheumatoid arthritis, or osteoarthritis. However, the effect of krill oil on mild knee pain has not yet been determined.

    OBJECTIVE: To assess the effect of krill oil on mild knee pain.

    DESIGN: A randomized, double-blind, parallel-group, placebo-controlled trial of fifty adults (38-85 years old) with mild knee pain attending the Fukushima Orthopedic Clinic (Tochigi, Japan) between September 2014 and March 2015.

    INTERVENTIONS: Participants were randomized to receive 2 g per day of either krill oil or an identical placebo for 30 days.

    OUTCOMES: The primary outcome was improvement in subjective symptoms of knee pain as assessed by the Japanese Knee Osteoarthritis Measure (JKOM) and Japanese Orthopaedic Association score (JOA). Secondary outcomes included blood and urine biochemical parameters.

    RESULTS: Both the placebo and krill oil groups showed significant improvements in the questions in the JKOM and JOA questionnaires after administration. After the intervention, krill oil group showed more improvements than placebo group in two questions regarding the pain and stiffness in knees in JKOM. Controlling for age, sex, weight, and smoking and drinking habits, krill oil significantly mitigated knee pain in sleeping (P < 0.001), standing (P < 0.001) and the range of motion of both right and left knees (both P = 0.011) compared to placebo. Krill oil administration raised plasma EPA (P = 0.048) and EPA/AA ratio (P = 0.003). CONCLUSION: This study indicates that krill oil administration (2 g/day, 30 days) improved the subjective symptoms of knee pain in adults with mild knee pain. Be well! JP

  32. JP Says:

    Updated 12/27/18:

    Lipids Health Dis. 2018 Dec 20;17(1):287.

    Prospective, randomized, double-blinded, placebo-controlled study on safety and tolerability of the krill powder product in overweight subjects with moderately elevated blood pressure.

    BACKGROUND: Krill powder is rich in bioactive ingredients such as eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), phospholipids, protein and astaxanthin. Containing dominantly EPA, it is considered to be effective in lowering lipids, foremost serum triglycerides and LDL cholesterol. Krill-derived protein hydrolysates/peptides may have positive effect on blood pressure and astaxanthin has anti-oxidative and anti-inflammatory properties. Thus, krill powder has a lot of potential in improving lipid and metabolic profile and reinforcing the activity of the antioxidant system. However, randomized clinical trials on krill powder are scarce and systematic data of krill meal on human safety is limited. Some of the earlier studies have reported several, non-serious adverse events, mostly related to gastrointestinal tract, but systematic sufficiently powered study on safety is lacking. The aim of this study was to collect data on safety and tolerability of krill powder in humans and simultaneously gain efficacy data by measuring the risk factors for cardiovascular disease.

    METHODS: The study was a randomised, double-blinded, placebo-controlled intervention study with 35 overweight subjects with mildly or moderately elevated blood pressure, who took 4 g krill oil powder or 4 g of placebo during an 8-week follow-up period. The study consisted of a pre-screening, screening, day 0 baseline (randomization visit) and three follow-up visits on days 14, 28 and 56. The reported adverse events in the groups were compared as primary endpoint and haematological safety parameters and changes in systolic and diastolic pressure and blood total and lipoprotein lipids were measured as secondary end points.

    RESULTS: There were in total 80 reported adverse events during the follow-up; 50 in placebo and 30 in krill powder group. Gastrointestinal symptoms (flatulence, heartburn and diarrhea) were the most commonly reported among those probably related to the test products. No serious adverse events were reported. The mean value of all measured hematology variables remained within the reference values in all study subject and no significant changes were observed in blood pressure or lipid values.

    CONCLUSIONS: The results seem to indicate that using krill powder as a source for EPA and DHA is safe in therapeutic dose and the risk of adverse events, let alone serious ones, is low.

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