For preventing and reversing the progression of hardening of the arteries after angioplasty: 6 grams of fish oil daily starting one month before angioplasty and continuing for one months after, followed by 3 grams daily for 6 months thereafter has been used. Also, 15 grams of fish oil has been taken daily for 3 weeks before angioplasty and for 6 months thereafter.
In a U.K. study, children of mothers who ate more than 12 ounces a week actually scored better on tests of verbal I.Q., social behavior, and development and communication than children of mothers who ate none. In the Seychelles Islands, where people average 12 fish meals -- not ounces -- a week, there are no reports of links between mercury exposure and poor outcomes in children. These studies suggest that eating less than 12 ounces of fish each week could do more harm to a child's developing neurological system than mercury poisoning.
To reach the required dose of EPA for treating certain conditions such as depression, CVD or CFS/ME you would need to take approximately 1-2 grams of ‘free EPA’ daily. Even with a concentrated omega-3 fish oil supplement, offering 180 mg excess EPA over DHA, this would require 10-20 capsules daily – significant in terms of volume and cost, and not efficient in terms of uptake in the body as our capacity for fat absorption is limited. The most effective and efficient way to ensure high EPA uptake in the body rapidly is to supplement with pure EPA for a minimum of 3-6 months.

Evidence in the population generally does not support a beneficial role for omega−3 fatty acid supplementation in preventing cardiovascular disease (including myocardial infarction and sudden cardiac death) or stroke.[4][19][20][21] A 2018 meta-analysis found no support that daily intake of one gram of omega-3 fatty acid in individuals with a history of coronary heart disease prevents fatal coronary heart disease, nonfatal myocardial infarction or any other vascular event.[6] However, omega−3 fatty acid supplementation greater than one gram daily for at least a year may be protective against cardiac death, sudden death, and myocardial infarction in people who have a history of cardiovascular disease.[22] No protective effect against the development of stroke or all-cause mortality was seen in this population.[22] Eating a diet high in fish that contain long chain omega−3 fatty acids does appear to decrease the risk of stroke.[23] Fish oil supplementation has not been shown to benefit revascularization or abnormal heart rhythms and has no effect on heart failure hospital admission rates.[24] Furthermore, fish oil supplement studies have failed to support claims of preventing heart attacks or strokes.[7]


Children, in particular, seem to experience problems with sleep when they don’t get enough omega-3 fatty acids in their diets. In adults, low omega-3 levels are associated with obstructive sleep apnea. One reason for this may be that low omega-3s are linked to lower levels of melatonin, the hormone partly responsible for helping you to get to sleep in the first place.
What makes omega-3 fats special? They are an integral part of cell membranes throughout the body and affect the function of the cell receptors in these membranes. They provide the starting point for making hormones that regulate blood clotting, contraction and relaxation of artery walls, and inflammation. They also bind to receptors in cells that regulate genetic function. Likely due to these effects, omega-3 fats have been shown to help prevent heart disease and stroke, may help control lupus, eczema, and rheumatoid arthritis, and may play protective roles in cancer and other conditions.
So why is an excess of DHA detrimental and an excess of EPA useful? DHA has a larger structure with two extra carbons and two extra double bonds, so it literally takes up more space in cell membranes than EPA. On the one hand, this is important because DHA plays a structural role in maintaining the fluidity of cell membranes ( essential for the normal function of proteins, channels and receptors that are also embedded in the membrane), but if a cell membrane becomes too saturated with DHA it can become too fluid, which can have a negative effect on cell function. EPA, on the other hand, is constantly utilised and always in demand.
Studies don’t seem to mention blood content of omega 6, or saturated fats–the overall balnce of triglycerides, so they seem to have been done in a “vacuum”. At least, the data is so presented. Also, high protein may be an issue not being tested, but hovering in the background of the participants’ diets. Many “miracle cures”, and I wish it wasnt so, are being not only “debunked”, but “proven” outright dangerous.
Nielsen, A. A., Jorgensen, L. G., Nielsen, J. N., Eivindson, M., Gronbaek, H., Vind, I., Hougaard, D. M., Skogstrand, K., Jensen, S., Munkholm, P., Brandslund, I., and Hey, H. Omega-3 fatty acids inhibit an increase of proinflammatory cytokines in patients with active Crohn's disease compared with omega-6 fatty acids. Aliment.Pharmacol.Ther. 2005;22(11-12):1121-1128. View abstract.
Badia-Tahull, M. B., Llop-Talaveron, J. M., Leiva-Badosa, E., Biondo, S., Farran-Teixido, L., Ramon-Torrell, J. M., and Jodar-Masanes, R. A randomised study on the clinical progress of high-risk elective major gastrointestinal surgery patients treated with olive oil-based parenteral nutrition with or without a fish oil supplement. Br.J.Nutr. 2010;104(5):737-741. View abstract.
The bottom line of all that is that there was no clear health benefit from consuming omega-3 fatty acids in food or supplements. There was a suggestion of a possible benefit from LCn3 on cardiac events, but this did not hold up when they took into consideration the quality of the evidence. The better trials, with less risk of bias, tended to be negative.
The contents of this website are for educational purposes and are not intended to offer personal medical advice. You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The Nutrition Source does not recommend or endorse any products.

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.

*Swordfish contains high levels of mercury, as does shark, king mackerel, and tilefish (sometimes called golden bass or golden snapper). Women who are or may become pregnant, nursing mothers, and young children should avoid these high-mercury species of fish, but can eat up to 12 ounces (two average meals) a week of a variety of fish and shellfish that are lower in mercury.
Davidson, M. H., Stein, E. A., Bays, H. E., Maki, K. C., Doyle, R. T., Shalwitz, R. A., Ballantyne, C. M., and Ginsberg, H. N. Efficacy and tolerability of adding prescription omega-3 fatty acids 4 g/d to simvastatin 40 mg/d in hypertriglyceridemic patients: an 8-week, randomized, double-blind, placebo-controlled study. Clin Ther 2007;29(7):1354-1367. View abstract.
Stiefel, P., Ruiz-Gutierrez, V., Gajon, E., Acosta, D., Garcia-Donas, M. A., Madrazo, J., Villar, J., and Carneado, J. Sodium transport kinetics, cell membrane lipid composition, neural conduction and metabolic control in type 1 diabetic patients. Changes after a low-dose n-3 fatty acid dietary intervention. Ann Nutr Metab 1999;43(2):113-120. View abstract.
It is also believed that women who do not have a sufficient intake of EPA and DHA in their diet suffer from depression after childbirth, as there is a transfer of some amount of brain mass from the mother to the child in the last stages of pregnancy. Thus, it is very beneficial to consume fish oil either by eating fish or taking fish oil supplements, tablets, capsules, or pills during pregnancy for the overall development of the child and the well-being of the mother. However, it should be noted that fish oil obtained from the liver of the fish, example – cod liver oil, should not be consumed during pregnancy as cod liver oil is high in retinol and vitamin A, which are usually known to cause birth defects.
Fish oil is a concentrated source of omega-3 fats, which are also called ω-3 fatty acids or n-3 fatty acids. To get more scientific, omega-3s are long-chain polyunsaturated fatty acids, or PUFAs. Our bodies are able to make most of the fats we need need, but that’s not true for omega-3 fatty acids. When it comes to these essential fats, we need to get them from omega-3 foods or supplements.
Oftentimes this could be a result of poor body composition, poor activity levels, or other things, like a low-quality diet. Now, for other people, I do think it’s the case that for people who do not eat fish and for people whose animal products, especially their eggs, are mostly from animals fed grains rather than pasture-raised animals or who don’t eat eggs, I think in those cases there is an argument for fish oil in the sense that those people are probably not going to get enough omega-3 fatty acids, but the better argument might be: Eat pastured eggs or eat fish. Even eating an oily fish like salmon once or twice a week is probably good enough to provide the omega-3 fatty acids that you need. Eating some pastured egg yolks every day is probably good enough to provide for the omega-3 fatty acids that you need.
In many cases, people are recommended to consume fish oil because it is an easy way to get additional omega-3 fatty acids into their diet. Omega-3 fats can be used to reduce swelling or to prevent blood clots which could cause major cardiovascular damage. There are many other conditions which can be decreased or improved with the use of fish oil. In most cases fish oil is used to help reduce high triglycerides which can cause serious conditions like diabetes or heart disease.

Back in 2013, a study came out that made a lot of people concerned about fish oil supplements and cancer. The study, published in the Journal of the National Cancer Institute, showed that men who consume the largest amount of fish oil had a 71 percent higher risk of high-grade prostate cancer and a 43 percent increase in all types of prostate cancer. The study was conducted on 2,227 men, of which 38 percent of the men already had prostate cancer. (39)
The chemical structure of eicosapentaenoic acid and docosahexaenoic acid. Eicosapentaenoic acid consists of 20 carbons (C20) with 5 double bonds, and the last unsaturated carbon is located third from the methyl end (n-3). Do-cosahexaenoic acid consists of 22 carbons (C22) with 6 double bonds, and also with the3 last unsaturated carbon located third from the methyl end (n-3). Adapted with permission from Frishman et al, eds. Cardiovascular Pharmacotherapeutics. New York, NY: McGraw Hill; 2003.3
56. Davidson MH, Stein EA, Bays HE, et al. COMBination of prescription Omega-3 with Simvastatin (COMBOS) Investigators. Efficacy and tolerability of adding prescription omega-3 fatty acids 4 g/d to simvastatin 40 mg/d in hypertriglyceridemic patients: an 8-week, randomized, double-blind, placebo-controlled study. Clin Ther. 2007;29:1354–1367. [PubMed]
Studies have also found that omega-3 fatty acids from fish oil are associated with improved survival rates for heart attack victims. A study published in the medical journal Circulation found that people who took a high dose of fish oil each for six months following the occurrence of a heart attack actually improved their hearts’ overall functioning and also reduced biomarkers of systemic inflammation. (20)
In lab experiments, animals given krill showed improved navigation skills. What this means is that they achieved higher levels of cognition and memory required to navigate complex territory.28 In addition, research shows that animals supplemented with krill oil showed significantly fewer signs of depression and resignation. This improvement in mood was equivalent to the effect of the prescription anti-depressant drug imipramine (Tofranil®).29
Warfarin (Coumadin) is used to slow blood clotting. Fish oil also might slow blood clotting. Taking fish oil with warfarin might slow blood clotting too much and increase the risk of bleeding. However, conflicting results suggests that fish oil does not increase the effects of warfarin. Until more is known, use cautiously in combination with warfarin. Have your blood checked regularly, as your dose of warfarin (Coumadin) might need to be changed.
Fish oil can be consumed in various ways such as capsules or can be included in daily meals. The dosage should not exceed 3 fish oil capsules per day. 1000mg of fish oil contains approximately 300mg omega-3 fatty acids so you can accordingly use the amount of fish oil in your meals. A daily intake of 3000mg or less is safe for all. Pregnant and lactating women can consume approximately 3200 mg per day.
Weak bones (osteoporosis). Research suggests that taking fish oil alone or together with calcium and evening primrose oil slows the rate of bone loss and increases bone density at the thigh bone (femur) and spine in elderly people with osteoporosis. But taking fish oil does not slow bone loss in older people with osteoarthritis in the knee but without weak bones.
×