Fish oil has only a small benefit on the risk of premature birth.[43][44] A 2015 meta-analysis of the effect of omega−3 supplementation during pregnancy did not demonstrate a decrease in the rate of preterm birth or improve outcomes in women with singleton pregnancies with no prior preterm births.[45] A systematic review and meta-analysis published the same year reached the opposite conclusion, specifically, that omega−3 fatty acids were effective in "preventing early and any preterm delivery".[46]
The evidence linking the consumption of marine omega−3 fats to a lower risk of cancer is poor.[8][13] With the possible exception of breast cancer,[8][14][15] there is insufficient evidence that supplementation with omega−3 fatty acids has an effect on different cancers.[5][16] The effect of consumption on prostate cancer is not conclusive.[8][15] There is a decreased risk with higher blood levels of DPA, but an increased risk of more aggressive prostate cancer was shown with higher blood levels of combined EPA and DHA.[17] In people with advanced cancer and cachexia, omega−3 fatty acids supplements may be of benefit, improving appetite, weight, and quality of life.[18]
Norris, J. M., Yin, X., Lamb, M. M., Barriga, K., Seifert, J., Hoffman, M., Orton, H. D., Baron, A. E., Clare-Salzler, M., Chase, H. P., Szabo, N. J., Erlich, H., Eisenbarth, G. S., and Rewers, M. Omega-3 polyunsaturated fatty acid intake and islet autoimmunity in children at increased risk for type 1 diabetes. JAMA 9-26-2007;298(12):1420-1428. View abstract.
Several large trials have evaluated the effect of fish or fish oils on heart disease. In the Gruppo Italiano per lo Studio della Sopravvivenza nell’Infarto Miocardio (known as the GISSI Prevention Trial), heart attack survivors who took a 1-gram capsule of omega-3 fats every day for three years were less likely to have a repeat heart attack, stroke, or die of sudden death than those who took a placebo. (2) Notably, the risk of sudden cardiac death was reduced by about 50 percent. In the more recent Japan EPA Lipid Intervention Study (JELIS), participants who took EPA plus a cholesterol-lowering statin were less likely to have a major coronary event (sudden cardiac death, fatal or nonfatal heart attack, unstable angina, or a procedure to open or bypass a narrowed or blocked coronary artery) than those who took a statin alone. (3)
Doses for depression range from less than 1 g/day to 10 g/day, but most studies use doses between 1 and 2 g/day. In my practice, I recommend 1 to 2 g/day of an EPA+DHA combination, with at least 60% EPA, for major depression. I am more cautious in patients with bipolar depression, because the omega-3s may bring on mania, as can most antidepressants. In these individuals, I recommend using omega-3 cautiously, and preferably in combination with a prescription mood stabilizer.
About the only exception are wild-caught Alaskan salmon and very small fish like sardines. The highest concentrations of mercury are found in large carnivorous fish like tuna, sea bass, and marlin. You may need to be especially cautious of canned tuna as well, as independent testing by the Mercury Policy Project found that the average mercury concentration in canned tuna is far over the "safe limits" of the Environmental Protection Agency (EPA).

Throughout their history, the Council for Responsible Nutrition and the World Health Organization have published acceptability standards regarding contaminants in fish oil. The most stringent current standard is the International Fish Oils Standard.[108][non-primary source needed] Fish oils that are molecularly distilled under vacuum typically make this highest-grade; levels of contaminants are stated in parts per billion per trillion.[citation needed][109]


Sala-Vila A, Díaz-López A, Valls-Pedret C, et al.; Prevención con Dieta Mediterránea (PREDIMED) Investigators. Dietary marine ?-3 fatty acids and incident sight-threatening retinopathy in middle-aged and older individuals with type 2 diabetes: Prospective investigation from the PREDIMED trial. JAMA Ophthalmol. 2016;134(10):1142-1149. View abstract.


Not all forms of fish oil may be equally digestible. Of four studies that compare bioavailability of the glyceryl ester form of fish oil vs. the ethyl ester form, two have concluded the natural glyceryl ester form is better, and the other two studies did not find a significant difference. No studies have shown the ethyl ester form to be superior, although it is cheaper to manufacture.[114][115]
Jump up ^ Kwak SM, Myung SK, Lee YJ, Seo HG (May 2012). "Efficacy of omega-3 fatty acid supplements (eicosapentaenoic acid and docosahexaenoic acid) in the secondary prevention of cardiovascular disease: a meta-analysis of randomized, double-blind, placebo-controlled trials". Archives of Internal Medicine. 172 (9): 686–94. doi:10.1001/archinternmed.2012.262. PMID 22493407.
AMA Manual of Style Art and Images in Psychiatry Breast Cancer Screening Guidelines Colorectal Screening Guidelines Declaration of Helsinki Depression Screening Guidelines Evidence-Based Medicine: An Oral History Fishbein Fellowship Genomics and Precision Health Health Disparities Hypertension Guidelines JAMA Network Audio JAMA Network Conferences Med Men Medical Education Opioid Management Guidelines Peer Review Congress Research Ethics Sepsis and Septic Shock Statins and Dyslipidemia Topics and Collections
Jump up ^ Martins, Julian G (2009). "EPA but Not DHA Appears to Be Responsible for the Efficacy of Omega-3 Long Chain Polyunsaturated Fatty Acid Supplementation in Depression: Evidence from a Meta-Analysis of Randomized Controlled Trials". Journal of the American College of Nutrition. 28 (5): 525–42. doi:10.1080/07315724.2009.10719785. PMID 20439549.
This systematic review and meta-analysis of clinical trials conducted on participants with clinical anxiety symptoms provides the first meta-analytic evidence, to our knowledge, that omega-3 PUFA treatment may be associated with anxiety reduction, which might not only be due to a potential placebo effect, but also from some associations of treatment with reduced anxiety symptoms. The beneficial anxiolytic effects of omega-3 PUFAs might be stronger in participants with specific clinical diagnoses than in those without specific clinical conditions. Larger and well-designed clinical trials should be performed with high-dose omega-3 PUFAs, provided as monotherapy and as adjunctive treatment to standard therapy.
Disclaimer: The entire contents of this website are based upon the opinions of Dr. Mercola, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Mercola and his community. Dr. Mercola encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional. If you are pregnant, nursing, taking medication, or have a medical condition, consult your health care professional before using products based on this content.
Fish oil supplements have been promoted as easy way to protect the heart, ease inflammation, improve mental health, and lengthen life. Such claims are one reason why Americans spend more than $1 billion a year on over-the-counter fish oil. And food companies are adding it to milk, yogurt, cereal, chocolate, cookies, juice, and hundreds of other foods.
ACS Breast Cancer Screening Guideline CDC Guideline for Prescribing Opioids CDC Guideline for Prevention of Surgical Site Infections Consensus Definitions for Sepsis and Septic Shock Global Burden of Cancer, 1990-2016 Global Burden of Disease in Children, 1990-2013 Global Burden of Hypertension, 1990-2015 Global Firearm Mortality, 1990-2016 Health Care Spending in the US and Other High-Income Countries Income and Life Expectancy in the US JNC 8 Guideline for Management of High Blood Pressure President Obama on US Health Care Reform Screening for Colorectal Cancer Screening for Depression in Adults Screening for Prostate Cancer Statins for Primary Prevention of Cardiovascular Disease The State of US Health, 1990-2016 US Burden of Cardiovascular Disease, 1990-2016 WMA Declaration of Helsinki, 7th Revision
Henneicke-von Zepelin, H. H., Mrowietz, U., Farber, L., Bruck-Borchers, K., Schober, C., Huber, J., Lutz, G., Kohnen, R., Christophers, E., and Welzel, D. Highly purified omega-3-polyunsaturated fatty acids for topical treatment of psoriasis. Results of a double-blind, placebo-controlled multicentre study. Br J Dermatol 1993;129(6):713-717. View abstract.
Wohl, D. A., Tien, H. C., Busby, M., Cunningham, C., Macintosh, B., Napravnik, S., Danan, E., Donovan, K., Hossenipour, M., and Simpson, R. J., Jr. Randomized study of the safety and efficacy of fish oil (omega-3 fatty acid) supplementation with dietary and exercise counseling for the treatment of antiretroviral therapy-associated hypertriglyceridemia. Clin.Infect.Dis. 11-15-2005;41(10):1498-1504. View abstract.
In later life, cognitive function and brain deterioration may become a concern. Once again, maintaining high levels of EPA has been shown to lower the risk of developing and worsening cognitive decline and dementia. If, however, you know someone who already has a diagnosis of dementia or Alzheimer’s, their brain has already been damaged and needs structural support. At this point, DHA becomes important again and taking a high-EPA product that contains 250mg of DHA also is important to prevent further loss of brain tissue.
Our Clinical Services Team - staffed by clinicians and other nutritional experts - answer technical questions about our nutritional formulas and the most effective ways to recommend them in a variety of protocols. And our product representatives help practitioners grow their business in many more ways than suggesting practice-appropriate nutritional products.
The effect of fish oil on incident atrial fibrillation has not been studied in large randomized trials, and observational population-based trials show mixed results. The Danish Diet, Cancer and Health Study, and the Rotterdam Study followed 47,000 and 5100 middle-aged adults, respectively.45,46 Neither study found that the consumption of fish oil affected the incidence of atrial fibrillation. Similar findings were seen in the Women’s Health Initiative where there was no association between fish and omega-3 FA intake regarding incident atrial fibrillation.47 However, in a 12-year prospective, observational study of 4815 adults over the age of 65, daily fish consumption was associated with a 31% risk reduction in incident atrial fibrillation.48

Heavy metal poisoning by the body's accumulation of traces of heavy metals, in particular mercury, lead, nickel, arsenic, and cadmium, is a possible risk from consuming fish oil supplements.[medical citation needed] Also, other contaminants (PCBs, furans, dioxins, and PBDEs) might be found, especially in less-refined fish oil supplements.[citation needed] However, heavy metal toxicity from consuming fish oil supplements is highly unlikely, because heavy metals selectively bind with protein in the fish flesh rather than accumulate in the oil. An independent test in 2005 of 44 fish oils on the US market found all of the products passed safety standards for potential contaminants.[107][unreliable source?]
Like I mentioned earlier, there are no official guidelines for the proper amount of omega-3s you should consume each day. However, most organization agree that at least 2 servings of a 3.5 ounce serving of fish (preferably oily) each week is a good start. That equals about 500 milligrams of EPA/DHA each day. For treating disease, up to 4,000 milligrams per day is recommended by various studies, although values do vary. (96) It’s why a pescatarian diet can have such health protective effects.
It can be challenging to get the appropriate intake of EPA and DHA through diet alone, even though EPA and DHA are produced by water plants such as algae and are prevalent in marine animals. A shorter chain omega-3 fatty acid, α-linolenic acid (ALA),6 is a prominent component of our diet as it is found in many land plants that are commonly eaten, but it does not provide the health benefits seen with EPA and DHA. Although it is possible for the body to convert ALA to EPA and DHA by enlongase and desaturase enzymes, research suggests that only a small amount can be synthesized in the body from this process (8). For example, 1 study suggested that only ∼2 to 10% of ALA is converted to EPA or DHA (9), and other studies found even less: Goyens et al. (10) found an ALA conversion of ∼7% for EPA, but only 0.013% for DHA; Hussein et al. (11) found an ALA conversion of only 0.3% for EPA and <0.01% for DHA.
According to the Cardiovascular Research Institute in Maastricht in Netherlands, “Epidemiological studies show that replacing fat with carbohydrates may even be worse [than the Western-type high-fat diet] and that various polyunsaturated fatty acids (FA) have beneficial rather than detrimental effects on CVD (cardiovascular disease) outcome.” This includes fish-oil fatty acids with anti-inflammatory properties, which can help prevent and reverse a plethora of cardiovascular diseases. (19)

Weimann, A., Bastian, L., Bischoff, W. E., Grotz, M., Hansel, M., Lotz, J., Trautwein, C., Tusch, G., Schlitt, H. J., and Regel, G. Influence of arginine, omega-3 fatty acids and nucleotide-supplemented enteral support on systemic inflammatory response syndrome and multiple organ failure in patients after severe trauma. Nutrition 1998;14(2):165-172. View abstract.
Bemelmans, W. J., Broer, J., Feskens, E. J., Smit, A. J., Muskiet, F. A., Lefrandt, J. D., Bom, V. J., May, J. F., and Meyboom-de Jong, B. Effect of an increased intake of alpha-linolenic acid and group nutritional education on cardiovascular risk factors: the Mediterranean Alpha-linolenic Enriched Groningen Dietary Intervention (MARGARIN) study. Am J Clin Nutr 2002;75(2):221-227. View abstract.

One reason omega-3 fatty acids may be so beneficial to this many aspects of health could be that they help decrease system-wide inflammation. (49, 50, 51, 52, 53) Inflammation is at the root of most diseases and is related to the development of nearly every major illness, so by eating a nutrient-dense, anti-inflammatory diet, you give your body its best chance to fight disease like it was designed to do.
Fearon, K. C., Von Meyenfeldt, M. F., Moses, A. G., Van Geenen, R., Roy, A., Gouma, D. J., Giacosa, A., Van Gossum, A., Bauer, J., Barber, M. D., Aaronson, N. K., Voss, A. C., and Tisdale, M. J. Effect of a protein and energy dense n-3 fatty acid enriched oral supplement on loss of weight and lean tissue in cancer cachexia: a randomised double blind trial. Gut 2003;52(10):1479-1486. View abstract.

Thanks to fatdog11 for that informative post about PCB’s in fish-oil supplements. Are these same toxicity levels found in fish themselves, or possibly are these levels so high only in highly concentrated fish-oil products? Also, can fatdog11 please inform us more about algae-derived omega-3. What are the DHA and EPA levels in these capsules? What is the cost, and where can they be purchased?
I've done a lot of research on fish oil and Body Vega meets all of the important criteria. They have recommended levels of EPA and DHA and it is molecularly distilled, pharmaceutical grade. The price is reasonable and there are no fishy burps. I tried another brand in the past that met the criteria, but got tired of the fishy burps. I switched to Body Vega a few months ago and have been pleased. So yes, you can find an excellent fish oil without tasting it 30 minutes later. Another good thing about this fish oil compared to one I've tried in the past is that you only need 2 daily capsules compared to 3 with the other brand I tried.
Sekikawa, A., Curb, D., Ueshima, H., El-Saed, A., Kadowaki, T., Abbott, R. D., ... Kuller, L. H. (2008 August 5). Marine-derived n-3 fatty acids and atherosclerosis in Japanese, Japanese Americans, and Whites: a cross-sectional study. Journal of the American College of Cardiology 52(6), 417–424. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2736602/
ACS Breast Cancer Screening Guideline CDC Guideline for Prescribing Opioids CDC Guideline for Prevention of Surgical Site Infections Consensus Definitions for Sepsis and Septic Shock Global Burden of Cancer, 1990-2016 Global Burden of Disease in Children, 1990-2013 Global Burden of Hypertension, 1990-2015 Global Firearm Mortality, 1990-2016 Health Care Spending in the US and Other High-Income Countries Income and Life Expectancy in the US JNC 8 Guideline for Management of High Blood Pressure President Obama on US Health Care Reform Screening for Colorectal Cancer Screening for Depression in Adults Screening for Prostate Cancer Statins for Primary Prevention of Cardiovascular Disease The State of US Health, 1990-2016 US Burden of Cardiovascular Disease, 1990-2016 WMA Declaration of Helsinki, 7th Revision
Jump up ^ Talakoub, Lily; Neuhaus, Isaac M.; Yu, Siegrid S. (2008). "Chapter 2: Cosmoceuticals". In Alam, Murad; Gladstone, Hayes B.; Tung, Rebecca. Cosmetic Dermatology. Requisites in dermatology. Elsevier Health Sciences. p. 9. ISBN 9780702031434. Retrieved 2014-10-23. Other oils used as emollients include fish oil, petrolatum, shea butter, and sunflower seed oil.
Keck, P. E., Jr., Mintz, J., McElroy, S. L., Freeman, M. P., Suppes, T., Frye, M. A., Altshuler, L. L., Kupka, R., Nolen, W. A., Leverich, G. S., Denicoff, K. D., Grunze, H., Duan, N., and Post, R. M. Double-blind, randomized, placebo-controlled trials of ethyl-eicosapentanoate in the treatment of bipolar depression and rapid cycling bipolar disorder. Biol.Psychiatry 11-1-2006;60(9):1020-1022. View abstract.
Oe, H., Hozumi, T., Murata, E., Matsuura, H., Negishi, K., Matsumura, Y., Iwata, S., Ogawa, K., Sugioka, K., Takemoto, Y., Shimada, K., Yoshiyama, M., Ishikura, Y., Kiso, Y., and Yoshikawa, J. Arachidonic acid and docosahexaenoic acid supplementation increases coronary flow velocity reserve in Japanese elderly individuals. Heart 2008;94(3):316-321. View abstract.
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