Krill are shrimp-like crustaceans eaten by blue whale. The oil extracted from these crustaceans contains important omega-3 fatty acids such as EPA and DHA, found in fish oils. Krill oil also has a high amount of a potent antioxidant called astaxanthin along with small amounts of vitamin A and vitamin E, and perhaps small amounts of other beneficial compounds.

Benefit of Krill Oil supplements
Some studies indicate it to have potential benefit in maintaining healthy cholesterol and also to play a role in premenstrual syndrome and menstrual cramps. More research is needed before determining with confidence the role of this supplement in health and disease. I also need to see more research to determine if krill oil supplements offer any major advantages over fish oil supplements. Until several head to head comparisons are done as a treatment for various different medical conditions, it would be premature to claim that krill oil is better than fish oil, or vice versa. One option is to alternate their use, or to take one or two softgels of each daily. There are many web sites that claim their krill oil is the best, and as you probably know by now, this is a common occurrence in the vitamin industry. Until head to head comparative studies are done with various different brands on humans, no one can say with certainty that a krill oil product from one company is superior to one from a different company.

Q. Just read Neptune Krill Oil is good for arthritis - inflammation. My husband has been taking glucosamine chondroitin, MSM, omega 3 and primrose oil which has helped. However, his fingers are still very swollen and times and he has trouble making a fist, especially after working all day in construction. Do you know of any side affects from Neptune Krill Oil?
   A. I am not aware of any apparent negative reactions when used at reasonable amounts, for instance less than 4 or 5 softgels a day.

Krill or fish oil? Which is better?
The latter has a higher percentage of EPA and DHA fatty acids, however krill oil has the advantage of having astaxanthin, an important antioxidant, vitamins A and D, and possibly other nutrients such as small amounts of phospholipids. Therefore, one option is to use a softgel or two of each, or alternate their use. Since phospholipids can be easily obtained from food, such as eggs, or lecithin ( phosphatidylcholine is found in lecithin ), one wonders if krill oil supplements are necessary when a person eats a lot of fish, takes fish oil supplements, consumes a variety of vegetables and fruits, and has a diet with adequate intake of phospholipids and perhaps takes an astaxanthin supplement a couple of times a week.

Eur J Nutr. 2013. Krill oil versus fish oil in modulation of inflammation and lipid metabolism in mice transgenic for TNF-α. Our findings demonstrate that FO and KO are comparable dietary sources of n-3 PUFAs. However, when quantitatively similar doses of n-3 PUFAs are administered, KO seems to have a greater potential to promote lipid catabolism.

Lipids Health Dis. 2011. Incorporation of EPA and DHA into plasma phospholipids in response to different omega-3 fatty acid formulations--a comparative bioavailability study of fish oil vs. krill oil. Bioavailability of omega-3 fatty acids (FA) depends on their chemical form. Superior bioavailability has been suggested for phospholipid (PL) bound omega-3 FA in krill oil, but identical doses of different chemical forms have not been compared. In a double-blinded crossover trial, we compared the uptake of three EPA + DHA formulations derived from fish oil and krill oil.  The highest incorporation of EPA + DHA into plasma was provoked by krill oil, followed by fish oil. Due to high standard deviation values, there were no significant differences for DHA and the sum of EPA + DHA levels between the three treatments.

I read somewhere that fish oil can oxidized / become rancid in the body because it doesn't contain antioxidants, and therefore krill oil is better for that reason. Is this true?
    Since krill oil is not as available as fish oil, it is much more expensive. The former has some astaxanthin which acts as an antioxidant, but taking a small amount of vitamin E with fish oil pills can prevent oxidation. If fish oil pills are taken with a healthy meal, there are usually enough antioxidants in the food to prevent any oxidation of the omega-3 oils.

Allergy in those who are allergic to shellfish
I don't know for certain whether those with shellfish allergy would be able to take krill oil supplements. Just to be on the safe side, it may be a good idea to avoid krill oil pills until more research is available on this topic. I have not yet come across clinical studies regarding allergic reactions to krill oil consumption. There is a possibility that miniscule amounts of shellfish residues could be present in some products.

Reactivity of Shrimp Allergy-Related IgE Antibodies to Krill Tropomyosin.
Int Arch Allergy Immunol. 2007.
Krill, which morphologically resembles small shrimp, represents small ocean crustaceans and has been used for human consumption in Japan and some other countries. The major allergen in crustaceans has been reported to be tropomyosin, but the allergenicity of krill tropomyosin remains uncertain. Amino acid sequences of tropomyosin in two species of krill (Euphausia superba and E. pacifica) were deduced. The cross-reactivity in shrimp allergy-related IgE binding among krill, shrimp, lobster and crab tropomyosins was revealed. These observations suggest the allergic potential of krill tropomyosin.
   Comments: I don't know how much tropomyosin is present in krill oil supplements and whether even tiny residues would have a clinical effect in those who are allergic to shellfish. If you are allergic to shellfish, particularly if you are severely allergic to shellfish, use fish oils instead of krill oil supplements.

If one is allergic to fish, can they take krill oil?
   It's difficult to say since there are different types of fish allergies and different products from various companies have different residues in them. I don't know at this time.

I've eaten shrimp all my life and recently on a visit to an allergist i found out i was allergic to shrimp according to their skin tests. But other than a mild itching I don't experience any severe symptoms from consuming shrimp. I am interested in taking krill oil because of the outstanding health benefits. How many milligrams should i start out with and how should i gradually increase it to build up my tolerance of this oil? I know you might tell me to ask my allergist but i already know his answer would be to stay away from it, but i'm interested on getting your input and advice.
   Our role is not to give specific, individual advice in regards to dosage or how to combine medications or supplements. We just provide general information and it is up to the consumer, along with their health care provider, to decide what is best for them. There may be a cause of concern regarding allergy to krill in those who are allergic to shellfish.

Blood thinning and clotting, Interaction with aspirin or other blood thinners, Plavix, Coumadin, warfarin
Fatty acids such as EPA and DHA have blood thinning properties and you would need to discuss with your doctor regarding the benefits versus risks. We think small amounts of krill oil or fish oil, such as one softgel a day, should not have too much influence on blood clotting.

Q. On a krill oil bottle I recently purchased it says i should consult my doctor about taking it with aspirin. Can i or can i not take a baby aspirin (2-3 times a week or even daily) with one 300 mg of krill oil?
  A. Omega-3 oils have blood thinning properties. Most adults can benefit from taking such fatty acids than thin the blood and most benefit from using a baby aspirin 2 or 3 times a week. However, it is not possible to predict in your case whether this combination is beneficial or harmful. Each person has a different need for blood thinning depending or their genetics, diet, and other supplements and medications that are used concurrently.

Brain health, mental function improvement
Clin Interv Aging. 2013. Effects of krill oil containing n-3 polyunsaturated fatty acids in phospholipid form on human brain function: a randomized controlled trial in healthy elderly volunteers. Krill oil, rich in n-3 (omega-3) polyunsaturated fatty acids (PUFAs) incorporated in phosphatidylcholine, has been reported to have many effects on physiological function. We investigated the influence of ingestion of krill oil on cognitive function in elderly subjects. Forty-five healthy elderly males aged 61-72 years were assigned to receive 12 weeks of treatment with: medium-chain triglycerides as placebo; krill oil, which is rich in n-3 PUFAs incorporated in phosphatidylcholine; or sardine oil, which is abundant in n-3 PUFAs incorporated in triglycerides. Changes in oxyhemoglobin concentrations in the cerebral cortex during memory and calculation tasks were measured. During the working memory task, changes in oxyhemoglobin concentrations in the krill oil and sardine oil groups were significantly greater than those in the medium-chain triglyceride group at week 12.  This study provides evidence that n-3 PUFAs activate cognitive function in the elderly. This is especially the case with krill oil, in which the majority of n-3 PUFAs are incorporated into phosphatidylcholine, causing it to be more effective than sardine oil, in which n-3 PUFAs are present as triglycerides.

Cholesterol and lipid levels, lowering fat in the blood, triglycerides 
Nutr Rev. 2017. Lipid-modifying effects of krill oil in humans: systematic review and meta-analysis of randomized controlled trials. The effect of krill oil supplements on plasma lipid concentrations was assessed through a systematic review of the literature and a meta-analysis of available randomized controlled trials. Krill oil supplementation can reduce low-density lipoprotein cholesterol and triglycerides. Additional clinical studies with more participants are needed to assess the impact of krill oil supplementation on other indices of cardiometabolic risk and on the risk of cardiovascular outcomes.

Evaluation of the effects of Neptune Krill Oil on the clinical course of hyperlipidemia.
Altern Med Rev. 2004.
To assess the effects on blood lipids, specifically total cholesterol, triglycerides, low-density lipoprotein (LDL), and high-density lipoprotein (HDL), a multi-center, three-month, randomized study was done followed by a three-month, controlled follow-up of patients treated with 1 gram and 1.5 g krill oil daily. The results showed Krill oil 1-3 g per day to be effective in the reduction of glucose, total cholesterol, triglycerides, LDL, and HDL, compared to both fish oil and placebo. It appears that krill oil is effective for the management of high lipid levels by reducing total cholesterol, LDL, and triglycerides, and increasing HDL levels.

Lipids Health Dis. 2013. Chronic treatment with krill powder reduces plasma triglyceride and anandamide levels in mildly obese men. In this study, we report the effects of krill powder, which contains proteins (34%) in addition to krill oil (61%), on 11 obese men (average BMI of 32 kg/m2, age of 42 years and high plasma triglycerides) to a 24 week dietary supplementation with krill powder (4 g/day). The treatment produced, after 12 and 24 weeks, a significant increase in DHA and EPA in total plasma, a 59 and 84% decrease in anandamide plasma levels, and a 22 and 20% decrease in triglyceride levels, respectively. There was also a significant decrease in waist/hip ratio and visceral fat/skeletal muscle mass ratio at 24 weeks, but no change in body weight. These data confirm that dietary krill powder reduces peripheral endocannabinoid overactivity in obese subjects, and might ameliorate some parameters of the metabolic syndrome.

Diabetes and blood sugar
BMJ Open Diabetes Res Care. 2015. Effects of krill oil on endothelial function and other cardiovascular risk factors in participants with type 2 diabetes, a randomized controlled trial. The purpose of this trial was to evaluate the effect of krill oil supplementation, a source of ω-3 fatty acids, on cardiovascular disease risk factors and blood glucose control among participants with type 2 diabetes. A randomized, double-blind controlled cross-over trial was employed. Outcomes assessed were: endothelial function, blood lipids, glucose, glycated hemoglobin, serum antioxidant level, C peptide, and calculated Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) scores. Participants were randomized to either krill oil or olive oil supplementation for 4 weeks, underwent a 2-week washout period, and then crossed to the other supplementation for 4 weeks. All participants were then offered an additional 17 weeks of krill supplementation. Testing occurred at 3 time points: baseline, after first supplementation, and after second supplementation. Testing also occurred after an optional 17 weeks of krill oil supplementation. Difference scores were calculated for each participant in both sequences (ie, differences in outcome measures in the first and second period of the sequence). A total of 47 participants were included in the initial cross-over study. Participants who received krill oil for 4 weeks had an improvement in their endothelial function and a reduction in blood C peptide levels and HOMA scores as compared with the olive oil. A total of 34 participants completed the additional 17-week supplementation period. When compared with their respective baseline measures, these participants had a statistically significant improvement in endothelial function and blood high-density lipoprotein (HDL). Krill oil may lead to moderate improvement of cardiovascular risks, specifically endothelial dysfunction and HDL in patients with type 2 diabetes.

Intestinal health
Dig Liver Dis. 2016. Krill oil reduces intestinal inflammation by improving epithelial integrity and impairing adherent-invasive Escherichia coli pathogenicity. Krill oil improves intestinal barrier integrity and epithelial restitution during inflammation and controls bacterial adhesion and invasion to epithelial cells. Thus, krill oil may represent an innovative tool to reduce intestinal inflammation.

Front Microbiol. 2017. Modulation of the Gut Microbiota by Krill Oil in Mice Fed a High-Sugar High-Fat Diet. Multiple lines of evidence suggest that the gut microbiota plays vital roles in metabolic diseases such as hyperlipidemia. Previous studies have confirmed that krill oil can alleviate high lipid levels. The results obtained in this study suggest that the structural alterations in the gut microbiota induced by krill oil treatment were dose-dependent and associated with the alleviation of hyperlipidemia.

Liver health
I have recently been taken off Lipitor due to the results of my last two hepatic function panels. I am looking for holistic alternatives that will not contribute to liver damage. My doctor is unsure if I have fatty liver or not at this point as I have been sick quite a bit this winter. Does krill oil help or harm a fatty liver? I want to be careful about what I add to my diet and certainly don’t want to do any harm. I appreciate the information on your website and the way you don’t ‘over-hype’ products but give sound scientific information.
    I have no reason to believe that taking 2 or 3 krill oil pills a day would harm the liver.

PMS
Krill Oil is an extract from Antarctic krill that is rich in cell membrane building blocks consisting of omega-3 fatty acids (EPA and DHA). Although beneficial for both men and women, Neptune Krill Oil may be tried to see if there is temporary relief of PMS symptoms. Fish oils may also be helpful for PMS.

Evaluation of the effects of Neptune Krill Oil on the management of premenstrual syndrome and dysmenorrhea.
Alternative Med Rev. 2003.
This study was undertaken to evaluate the effectiveness of Neptune Krill Oil in the management of premenstrual syndrome and dysmenorrhea (painful cramps) and to also compare it to fish oils. The treatment period was three months with either Neptune krill oil or omega-3 fish oil. Results showed an improvement within the Neptune krill oil group as well as between-group comparison to fish oil, after three cycles or 45 and 90 days of treatment. Data analysis showed a significant reduction of the number of pain killers used for dysmenorrhea within the Neptune krill oil group.

Children
I am aware the krill oil supplement studies on children are limited and I would still like a dosage recommendation for a three year old.
   Some children may benefit from krill oil supplements whereas others may not. Much depends on the child's diet. As a general guideline, I can't see any harm giving one capsule of a krill oil supplement once or twice a week to a three year old child if the pediatrician approves.

What is the dosage for children, 10 yr old specifically. What are the parameters for pediatric dosage, if any?
   Krill oil has hardly been studied in children, but a softgel a day as a routine supplement should be quite safe.

Environmental concerns
Krill is a tiny crustacean that lives in cold bodies of water. It is comparable in EPA and DHA levels to fish but also has some potent antioxidants like astaxanthin. Sounds good right? Well there is one huge problem. They are whale food, and they are a declining species. Reports beginning in the late 90's didn't look good, and they are no better now. In 1997, Earth Observatory noted that as ice cover becomes less prominent, krill suffer. Not only that, but licenses to fish for krill commercially are likely to go bust since in some areas, populations have fallen by 80% in the past 30 years.

Neptune Technologies letter received in 2006
Dear Dr. Sahelian, I have read your web site which I have found well done but for one aspect. As you know, animal populations fluctuate naturally over time. Antarctic Krill (Euphausia superba) populations do the same thing due to natural environmental fluctuating conditions. And until now there is no known scientific indication that it is a consequence of krill fishing and much less krill over fishing. For several years (since 1987) I have been and still am involved as oceanographer and developer in the task of exploiting krill. I am well aware that it is a sensible marine ecology topic.
   Neptune Technologies & Bioressources Inc. (NTB) has been co-founded in 1998 by Mr. Henri Harland, CEO and President, and I as a marine zooplanktonologist. Neptune Technologies & Bioressources Inc.’s processing plant has been in operation since Fall 2002. NTB’s processing plant extracts primarily the total lipid fraction of Antarctic Krill – Neptune Krill Oil (NKOTM) which results in a valuable residual of protein concentrate with active enzymes Neptune Krill Aquatein. The patented process in use – Neptune OceanExtract has been specially developed for krill processing. One mission of NTB as corporate citizen is to give access to human beings to the healthiest as possible substances obtained from a marine biomass with the lowest environmental impact on both marine (fishery) and terrestrial (processing site) ecosystems. We believe that there is an environmentally economical way to exploit a marine biomass under some conditions. The biomass must be abundant. The biomass yielded must not deprive predators. The biomass must be processed without residuals. If it is not the case then it will be used but never discarded. The biomass must reach the maximum added value possible on the market place. With that approach we believe then that the lowest quantities as possible of krill will be used contrary to the two main ways of exploiting it: as bait -what a pity- and aquaculture feed (as mentioned by Dr. Denzil MILLER, Executive Secretary, CCAMLR). For now, one can only say that the assumed declining Antarctic Krill population (Nature, November 2004) (1) can be a phenomenon simply isolated in time and space (2) is not yet corresponding necessarily to a general definite trend.
   Indeed, another Antarctic Krill huge population (estimated to tens of millions of tonnes) has been discovered in the far South Indian Ocean section of the Southern Ocean surrounding Antarctica between Australia and South Africa (below the tip of it) by Dr. Steve Nicol, Program Leader, Southern Ocean Ecosystems, Australian Antarctic Division (in Andrew Darby, Hobart, 2006, The Age Company Ltd., Antarctic researchers get a surprise and a thrill after moving in for the krill).
     It is somehow premature to claim that “licenses to fish Krill commercially are likely to go bust…”. Antarctic Krill fishery is under the surveillance and management principles of the 24-member nations of CCAMLR (Commission for the Conservation of Antarctic Marine Living Resources) based in Hobart, Tasmania, Australia. Although Antarctic Krill catch quotas decided by CCAMLR would probably stay the same over the next few years, one might ask to krill fishers that some precautionary catch procedures be more implemented. I would greatly appreciate that you take into account the actual updated information provided here when you will update your paper on Neptune Krill Oil. Luc A. RAINVILLE. M.Sc. Oceanography, Neptune Technologies & Bioressources Inc. V.-P. Marine Biomass Procurement, Director of Regulatory Affairs

Enzymotec krill oil company press release 2008
Israeli company Enzymotec has obtained GRAS status for its krill oil which the company hopes will allow it to commercialize the ingredient for use in functional foods in the US. Enzymtec entered the still immature market for krill oil last year, supplying the ingredient for use in dietary supplements. Competitor Neptune Technologies and Bioressources - which currently dominates the market for krill oil - also announced in recent weeks that its krill oil has achieved GRAS status. Most of the science to date has been conducted using Neptune Krill Oil (NKO). Enzymotec's offering is said to have a different composition, so research on NKO would not necessarily be transferable. However, Enzymotec has said it is also conducting clinical research into the health benefits of its ingredient. Krill, which means 'whale food' in Norwegian, are small shrimp-like marine crustaceans eaten by fish, birds and, in particular, whales. Krill are considered to have the largest biomass of any multi-cellular animal in the world - between 100 and 800 million tones. Despite this, the population has reduced in the past 30 years, resulting in some concern over its harvesting.

Questions
I am a doctor and was excited when I first read about this and given that I have high cholesterol (very responsive to statins) I decided to try going off statins and seeing the effects of Neptune krill oil. I took 2000 mg (4 capsules) a day for 2 months and saw no beneficial effect on cholesterol or any lipid fraction. I think krill oil is another example of a hyped up natural product that has not been well tested.
   A. Sometimes we tend to look at absolute numbers on lab studies rather than other important matters. For instance, krill oil is full of EPA and DHA. These fatty acids get incorporated in many tissues in the body, including eye, brain, skin, various organs, heart, etc., and may also lead to improved microcirculation and decreased blood viscosity. By just looking at total cholesterol and fractions, without taking into account the fatty acid composition of these fractions, and without taking into account the beneficial aspects of these fatty acids from krill oil on other parts of the body does not give us the full picture of the benefits. Doctors and drug companies make the mistake of looking at cholesterol levels as if it that is the most important thing in cardiovascular health. But there is no study that says taking statins will make one live longer. In fact, stating cause serious side effects in many people including muscle tissue damage. Who knows, taking a statin could lower cholesterol but then reduce life span? Whereas taking krill oil may not reduce cholesterol, but because of all the other potential benefits that fish oils provide, it may increase life span. This is all theoretical of course, but the main point I want to make is that looking at cholesterol numbers as if that is the most important thing is not being scientifically comprehensive.

I cannot find it available anywhere for sale as oil... is there a reason for this? If you're aware of any place where that I can purchase krill oil in oil form, I would be thankful for your direction.
   A. A quick search on the internet did not reveal any companies that sell it. Perhaps it is too expensive to have a full bottle of 4 ounces or the demand for it is not very high at this time.

After one week usage I can verify the following benefits from Krill oil: Within minutes of swallowing my eyesight improves. Its like I’ve switched from watching an old TV to a new HDTV. The definition and colours and contrast with vastly improved clarity is remarkable. Everything looks beautiful. Two other things, my skin has suffered quite a bit from the African sun with the development of large moles on my neck, again even through just the past weeks usage I’ve noticed what seems to me to be a reduction in size. Those moles have been there for years. This also goes for old boils that had left scar tissue, a huge reduction in size and surface appearance. The other thing is my skin is a lot less oily with the usual “black heads” on my nose almost completely disappearing. My whole skin tone feels younger and healthier. I wonder if I perhaps have till now just been Omega 3 deficient? Joint pain in my shoulder from an excess of youthful exuberance at gym also feels a lot better. I am amazed that something so simple can give such marked varied improvement to one’s health in such a short space of time. Thank you for informative website. Your passion and dedication for your work is received in kind.
    A. Fish oils, omega-3 fatty acids such as epa and dha do improve vision. Perhaps you were lacking these important fatty acids in your diet.

Other products available over the counter
Antarctic Krill Oil, 500 mg, 30 Softgels
KriaXantin Krill Oil is a high quality, solvent free extract from Antarctic krill that thrive wild in the pristine seas of Antarctica. This product is of benefit to men and women. For the time being, until I see actual studies, I prefer that it be refrigerated after the bottle is opened.
Supplement Facts per 2 softgels:
High Quality Antarctic Krill Oil 1000 mg, Yielding:
     Total Omega3 Fatty Acids 130 mg
     EPA (eicosapentaenoic acid) 50 mg
     DHA (docosahexaenoic acid) 20 mg
     Total Omega6 Fatty Acids 20 mg
     Astaxanthin 2.4 mg
     Plus, vitamins A and D
Buy Krill Oil supplement

Q. I am not able to swallow capsules. Would I be able to crush or bite the krill oil capsules to extract oil?
    A. It should make no difference on the effectiveness of this product as long as you find a way to ingest it and it ends up in your stomach.

Buy Neptune Krill Oil supplement NKO
You have the option to buy Kriaxanthin or to buy Neptune. Both are excellent products and we have not seen any studies comparing the two to know which is healthier to ingest. However, Neptune Technologies & Bioressources Inc. has done many studies with its product as seen below. Neptune and Kriaxanthin brand krill oil are both derived from the Antarctic. The softgel smells a little like fish, but not much. It does not seem to have much of a fish oil-like after taste.

Buy Neptune Krill oil supplement on sale
Source Naturals, Arctic Pure, buy Krill Oil, 500 mg, 120 Softgels