Humans are unable to place double bonds beyond position 9 on long chain polyunsaturated fatty acids (FA), making the omega-3 FA synthesized in plants and in marine microalgae essential elements to the human diet.1 Fish contain high levels of 2 omega-3 FA, eicosapentaenoic acid (EPA; C20:5 n-3), and docosahexaenoic acid [DHA]; C22:6 n-3)2,3 (Fig. 1). Many claims about the role of these omega-3 FA have been made in the prevention and treatment of cardiovascular disease. For instance, fish oil is seen as having a therapeutic role in coronary artery disease (CAD), heart failure, fatal and nonfatal arrhythmias, as well as offering an alternative or adjunct to the standard therapy for hypertriglyceridemia and diabetes. This review will highlight the potential mechanisms of fish oil on cardiovascular disease and provide an update of clinical trial results. The established uses in the treatment of hypertriglyceridemia and sources of omega-3 FA—both dietary and drug therapy—will be iterated, along with its potential application in combination with standard hypolipidemic agents. Finally, the limitations of current data will be addressed, as well as suggested recommendations for clinical use.
If you want to take higher doses of omega-3 fish oil supplements, talk to your doctor first. Your doctor can guide you in supplementing your diet with omega-3 fish oil. Also, your doctor can monitor all aspects of your health if you take higher doses of fish oil.For people with very high triglyceride levels, prescription omega-3 preparations are also available.

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 'essential' fatty acids were given their name when researchers found that they are essential to normal growth in young children and animals. The omega−3 fatty acid DHA, also known as docosahexaenoic acid, is found in high abundance in the human brain.[70] It is produced by a desaturation process, but humans lack the desaturase enzyme, which acts to insert double bonds at the ω6 and ω3 position.[70] Therefore, the ω6 and ω3 polyunsaturated fatty acids cannot be synthesized and are appropriately called essential fatty acids.[70]


DHA is vital for early brain development and maintenance, while EPA seems to be closely related to behavior and mood. Together, both molecules provide critical neuroprotective benefits.11 These neuroprotective effects are important for the prevention of age-related brain shrinkage (cortical atrophy). Aging adults with brain shrinkage often experience memory loss, cognitive decline, and an increase in depression.12-14
Because patients with depression experience rapid shrinking of their hippocampus, many strategies for relieving depression focus on increasing new brain cell growth in that specific area of the brain.23 There’s now evidence that increasing omega-3 intake, especially DHA, may be an effective way of treating or preventing depression, partly by protecting the hippocampus from further shrinkage.23
Dr. Holub has provided the questions and answers for several emails he has received over the years regarding omega-3 fatty acids for health.  If you have a question regarding omega-3, it is likely that Dr. Holub has answered it either here in this section, or elsewhere on the site (e.g. check the scientific overview section for general questions regarding omega-3).  To quickly find your answer, please use our search bar located in the top right section of this page.  After searching our site, and  you still cannot find the answer to your question, we invite you to ask Dr. Holub a question here.
The US National Institutes of Health lists three conditions for which fish oil and other omega-3 sources are most highly recommended: hypertriglyceridemia (high triglyceride level), preventing secondary cardiovascular disease, and hypertension (high blood pressure). It then lists 27 other conditions for which there is less evidence. It also lists possible safety concerns: "Intake of 3 grams per day or greater of omega-3 fatty acids may increase the risk of bleeding, although there is little evidence of significant bleeding risk at lower doses. Very large intakes of fish oil/omega-3 fatty acids may increase the risk of hemorrhagic (bleeding) stroke."[12]
As with other supplements, when it comes to quality, you get what you pay for. Life Time sources its omega-3 fish oil (both capsules and liquid) from sustainable fisheries off the coast of Chile. We only use oils from small, cold-water anchovy, sardine, and mackerel. It’s molecularly distilled to be sure it’s free of mercury, PCBs, and heavy metals. If your fish oil brand doesn’t name the species of fish it’s sourced from, or it lists larger, predatory species, the quality and purity of the oil could be less than optimal.
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The most widely available dietary source of EPA and DHA is oily fish, such as salmon, herring, mackerel, anchovies, menhaden, and sardines. Oils from these fish have a profile of around seven times as much omega−3 as omega−6. Other oily fish, such as tuna, also contain n-3 in somewhat lesser amounts. Consumers of oily fish should be aware of the potential presence of heavy metals and fat-soluble pollutants like PCBs and dioxins, which are known to accumulate up the food chain. After extensive review, researchers from Harvard's School of Public Health in the Journal of the American Medical Association (2006) [110] reported that the benefits of fish intake generally far outweigh the potential risks. Although fish are a dietary source of omega−3 fatty acids, fish do not synthesize them; they obtain them from the algae (microalgae in particular) or plankton in their diets.[111] In the case of farmed fish, omega-3 fatty acids is provided by fish oil; In 2009, 81% of the global fish oil production is used by aquaculture.[112]
A 2008 meta-study by the Canadian Medical Association Journal found fish oil supplementation did not demonstrate any preventative benefit to cardiac patients with ventricular arrhythmias.[36] A 2012 meta-analysis published in the Journal of the American Medical Association, covering 20 studies and 68,680 patients, found that Omega-3 Fatty Acid supplementation did not reduce the chance of death, cardiac death, heart attack or stroke.[37]
The differing actions of EPA and DHA, together with their competitive uptake, help to explain why studies that attempt to use standard fish oil therapeutically (where DHA and EPA are combined, in a natural ratio of approximately 1.5:1) are either less beneficial than expected, or even completely ineffective. Standard EPA/DHA fish oils are more suitable for everyday wellbeing, to compensate for a lack of fish in the diet and to meet a suggested intake.
^ Jump up to: a b c Aung T, Halsey J, Kromhout D, Gerstein HC, Marchioli R, Tavazzi L, Geleijnse JM, Rauch B, Ness A, Galan P, Chew EY, Bosch J, Collins R, Lewington S, Armitage J, Clarke R (March 2018). "Associations of Omega-3 Fatty Acid Supplement Use With Cardiovascular Disease Risks: Meta-analysis of 10 Trials Involving 77 917 Individuals". JAMA Cardiology. 3 (3): 225–34. doi:10.1001/jamacardio.2017.5205. PMC 5885893. PMID 29387889.
Finally, it is often assumed since there are not high levels of EPA in the brain, that it is not important for neurological function. Actually it is key for reducing neuro-inflammation by competing against AA for access to the same enzymes needed to produce inflammatory eicosanoids. However, once EPA enters into the brain it is rapidly oxidized (2,3). This is not the case with DHA (4). The only way to control cellular inflammation in the brain is to maintain high levels of EPA in the blood. This is why all the work on depression, ADHD, brain trauma, etc. have demonstrated EPA to be superior to DHA (5).
Special attention should also be given to the fact that most women have major deficiencies of omega-3. A 1991 study at the Mayo Clinic focused on 19 "normal" pregnant women consuming "normal diets," and it showed that all were deficient in omega-3 fats. Another study compared Inuit (Eskimo) women to Canadian women, and it revealed omega-3 deficiency in the milk of the Canadian nursing moms.
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Omega 3 fatty acids—found in supplements and naturally in some foods like certain fish, and nuts and seeds—have long been touted for their health benefits, especially heart health. Yet, a lot is still unknown, including whether it's better to get your omega 3 fats from pills or in food—and the debate continues regarding how much they may actually help you avoid heart disease.

The American Heart Association (AHA) has made recommendations for EPA and DHA due to their cardiovascular benefits: individuals with no history of coronary heart disease or myocardial infarction should consume oily fish two times per week; and "Treatment is reasonable" for those having been diagnosed with coronary heart disease. For the latter the AHA does not recommend a specific amount of EPA + DHA, although it notes that most trials were at or close to 1000 mg/day. The benefit appears to be on the order of a 9% decrease in relative risk.[106] The European Food Safety Authority (EFSA) approved a claim "EPA and DHA contributes to the normal function of the heart" for products that contain at least 250 mg EPA + DHA. The report did not address the issue of people with pre-existing heart disease. The World Health Organization recommends regular fish consumption (1-2 servings per week, equivalent to 200 to 500 mg/day EPA + DHA) as protective against coronary heart disease and ischaemic stroke.
A 2008 meta-study by the Canadian Medical Association Journal found fish oil supplementation did not demonstrate any preventative benefit to cardiac patients with ventricular arrhythmias.[36] A 2012 meta-analysis published in the Journal of the American Medical Association, covering 20 studies and 68,680 patients, found that Omega-3 Fatty Acid supplementation did not reduce the chance of death, cardiac death, heart attack or stroke.[37]
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To avoid fish oil supplements containing mercury or other harmful contaminants, purchase supplements from a reputable source that clearly tests for these health-hazardous contaminants in its products. These tests should be ideally conducted by a third-party, and a certificate of analysis should indicate the levels of purity from environmental toxins.
Damage to the kidneys caused the drug cyclosporine. Cyclosporine is a medication that reduces the chance of organ rejection after an organ transplant. Taking fish oil seems to prevent kidney damage in people taking this drug. Fish oil also seems to improve kidney function during the recovery phase following the rejection of a transplanted organ in people taking cyclosporine.
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