Abnormal cholesterol or fat levels in the blood (dyslipidemia). There is conflicting evidence about the effects of fish oil on cholesterol and fat levels in the blood. Some research shows that taking fish oil can lower triglyceride levels, low density lipoprotein (LDL or "bad") cholesterol, and increase high density lipoprotein (HDL or "good") cholesterol in people with abnormal cholesterol levels. However, other research shows that taking fish oil daily does not have this effect.

Researchers are taking a hard look at a different sort of balance, this one between possible effects of marine and plant omega-3 fats on prostate cancer. Results from the Health Professionals Follow-up Study and others show that men whose diets are rich in EPA and DHA (mainly from fish and seafood) are less likely to develop advanced prostate cancer than those with low intake of EPA and DHA. (6) At the same time, some-but not all-studies show an increase in prostate cancer and advanced prostate cancer among men with high intakes of ALA (mainly from supplements). However, this effect is inconsistent. In the very large Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, for example, there was no link between ALA intake and early, late, or advanced prostate cancer. (7)
The three types of omega-3s are APA, EPA and DHA. The first is a medium-chain fatty acid and must be converted into EPA before being synthesized by the body, and only about 1 percent of the APA consumed is able to be converted. EPA and DHA are already in a form ready to be synthesized (and are the subject of most scientific research regarding omega-3s).

Due to the anticipated heterogeneity, a random-effects meta-analysis was chosen rather than a fixed-effects meta-analysis because random-effects modeling is more stringent and incorporates an among-study variance in the calculations. The entire meta-analysis procedure was performed on the platform of Comprehensive Meta-analysis statistical software, version 3 (Biostat). Under the preliminary assumption that the scales for anxiety symptoms are heterogeneous among the recruited studies, we chose Hedges g and 95% confidence intervals to combine the effect sizes, in accordance with the manual of the Comprehensive Meta-analysis statistical software, version 3. Regarding the interpretation of effect sizes, we defined Hedges g values 0 or higher as a better association of treatment with reduced anxiety symptoms of omega-3 PUFAs than in controls. For each analysis, a 2-tailed P value less than .05 was considered to indicate statistical significance. When more than 1 anxiety scale was used in a study, we chose the one with the most informative data (ie, mean and standard deviation [SD] before and after treatment). We entered the primary outcome provided in the included articles or obtained from the original authors. As for the variance imputation, we mainly chose the mean and SD before and after treatment. Later, we entered the mean and SD and calculated the effect sizes based on the software option, standardized by post score SD. In the case of studies with 2 active treatment arms, we merged the 2 active treatment arms into 1 group. If these 2 active treatment arms belonged to different subgroups (ie, different PUFA dosage subgroups), we kept them separate. Regarding the numbers of participants counted, we chose intention-to-treat as our priority. If there were insufficient data in the intention to treat group (ie, some studies only provided the changes in anxiety severity in those participants completing trials), we chose instead the per-protocol numbers of participants.


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.
FDA pregnancy category C. It is not known whether Fish Oil will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using Fish Oil. It is not known whether omega-3 polyunsaturated fatty acids pass into breast milk or if this could harm a nursing baby. Do not use Fish Oil without telling your doctor if you are breast-feeding a baby. Do not give this medication to anyone under 18 years old.

A group out of India conducted a study published in Cancer Chemotherapy and Pharmacology based on the premise that “fish oil rich in n-3 polyunsaturated fatty acids has been preferred to chemosensitize tumor cells to anti-cancer drugs.” The study found that using 5-Fluorouracil (5-FU) to treat colorectal cancer along with fish oil increased the survival rate in carcinogen-treated animals. Researchers also found that the fish oil ameliorated hematologic depression, along with gastrointestinal, hepatic and renal toxicity caused by the 5-FU. (15)
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]
A group out of India conducted a study published in Cancer Chemotherapy and Pharmacology based on the premise that “fish oil rich in n-3 polyunsaturated fatty acids has been preferred to chemosensitize tumor cells to anti-cancer drugs.” The study found that using 5-Fluorouracil (5-FU) to treat colorectal cancer along with fish oil increased the survival rate in carcinogen-treated animals. Researchers also found that the fish oil ameliorated hematologic depression, along with gastrointestinal, hepatic and renal toxicity caused by the 5-FU. (15)
It helps maintain a good luster of the hair because omega-3 has growth stimulating properties since it provides nourishment to the follicles. It aids in the development of hair and in preventing hair loss. A good supply of protein is also necessary for hair growth, and since most fish varieties are rich in protein, eating fish helps to keep hair healthy.

Cochrane lead author, Dr. Lee Hooper from the University of East Anglia, UK said: “We can be confident in the findings of this review which go against the popular belief that long-chain omega 3 supplements protect the heart. This large systematic review included information from many thousands of people over long periods.  Despite all this information, we don’t see protective effects.

For example, large predatory fish like shark, swordfish, king mackerel, tilefish and albacore tuna can contain high levels of methyl mercury, a toxin that would override any health benefit, especially for the developing brains of fetuses and young children as well as for adults, Dr. Nesheim and Marion Nestle, professor emerita of nutrition, food studies and public health at New York University, noted in 2014 in an editorial in the American Journal of Clinical Nutrition. (Levels of mercury and other contaminants in fish have since declined somewhat but are not negligible.)


If you find yourself in a position where you are just not eating any of these foods, and you want to get enough omega-3 fatty acids, then I think fish oil is okay, but I would limit not the amount of fish oil but the amount listed on the label of EPA and DHA combined. I would limit that amount to around 250 milligrams per day because I don’t think most people need more than that. Some signs that you might not be getting enough omega-3 fatty acids include chronic low-grade inflammation, poor visual acuity, slower mental processing, trouble learning, and possibly Alzheimer’s disease and psychiatric conditions, like depression, anxiety, and attention deficit and hyperactivity disorder, ADHD.
Hernandez, D., Guerra, R., Milena, A., Torres, A., Garcia, S., Garcia, C., Abreu, P., Gonzalez, A., Gomez, M. A., Rufino, M., Gonzalez-Posada, J., Lorenzo, V., and Salido, E. Dietary fish oil does not influence acute rejection rate and graft survival after renal transplantation: a randomized placebo-controlled study. Nephrol.Dial.Transplant. 2002;17(5):897-904. View abstract.
The way that fish oil does that is to interfere with carbohydrate metabolism, and in insulin-resistant people or in people with specific genetic differences that might predispose them to having very high triglycerides, you do benefit from interfering that pathway with the fish oil, but I would actually try a low-carbohydrate diet in a lot of those situations to see if that helps with lowering triglycerides, or in the case of insulin resistance, I would try to address the insulin resistance at its root cause.
There have been conflicting results reported about EPA and DHA and their use with regard to major coronary events and their use after myocardial infarction. EPA+DHA has been associated with a reduced risk of recurrent coronary artery events and sudden cardiac death after an acute myocardial infarction (RR, 0.47; 95% CI: 0.219–0.995) and a reduction in heart failure events (adjusted HR: 0.92; 99% CI: 0.849–0.999) (34–36). A study using EPA supplementation in combination with a statin, compared with statin therapy alone, found that, after 5 y, the patients in the EPA group (n = 262) who had a history of coronary artery disease had a 19% relative reduction in major coronary events (P = 0.011). However, in patients with no history of coronary artery disease (n = 104), major coronary events were reduced by 18%, but this finding was not significant (37). This Japanese population already has a high relative intake of fish compared with other nations, and, thus, these data suggest that supplementation has cardiovascular benefits in those who already have sufficient baseline EPA+DHA levels. Another study compared patients with impaired glucose metabolism (n = 4565) with normoglycemic patients (n = 14,080). Impaired glucose metabolism patients had a significantly higher coronary artery disease HR (1.71 in the non-EPA group and 1.63 in the EPA group). The primary endpoint was any major coronary event including sudden cardiac death, myocardial infarction, and other nonfatal events. Treatment of impaired glucose metabolism patients with EPA showed a significantly lower major coronary event HR of 0.78 compared with the non–EPA-treated impaired glucose metabolism patients (95% CI: 0.60–0.998; P = 0.048), which demonstrates that EPA significantly suppresses major coronary events (38). When looking at the use of EPA+DHA and cardiovascular events after myocardial infarction, of 4837 patients, a major cardiovascular event occurred in 671 patients (13.9%) (39). A post hoc analysis of the data from these diabetic patients showed that rates of fatal coronary heart disease and arrhythmia-related events were lower among patients in the EPA+DHA group than among the placebo group (HR for fatal coronary heart disease: 0.51; 95% CI: 0.27–0.97; HR for arrhythmia-related events: 0.51; 95% CI: 0.24–1.11, not statistically significant) (39). Another study found that there was no significant difference in sudden cardiac death or total mortality between an EPA+DHA supplementation group and a control group in those patients treated after myocardial infarction (40). Although these last 2 studies appear to be negative in their results, it is possible that the more aggressive treatment with medications in these more recent studies could attribute to this.
Fish oil is oil derived from the tissues of oily fish. Fish oils contain the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), precursors of certain eicosanoids that are known to reduce inflammation in the body,[1][2] and have other health benefits, such as treating hypertriglyceridemia, although claims of preventing heart attacks or strokes have not been supported.[3][4][5][6] Fish oil and omega-3 fatty acids have been studied in a wide variety of other conditions, such as clinical depression,[7][8] anxiety,[9][10][11] cancer, and macular degeneration, yet benefits in these conditions have not been verified.[12]
So for those people who will not eat liver, cod liver oil on a daily basis can be a very good way of getting that. And you do benefit from the omega-3 fatty acids, and with the cod liver oil, it may even be unimportant to eat fish if you’re getting the cod liver oil, although it’s still better to focus on the fish, the egg yolks, and just add some of the cod liver oil.

For those who do not eat seafood, another way exists for you to get a healthy dose of EPA and DHA each day. Fish oil supplements, which are rich in EPA and DHA, can be made from a variety of fish, with the most common ones being halibut, tuna, salmon, cod liver, mackerel and herring. On average, one 3.5 ounce serving of fatty fish contains about 1 gram of omega-3s, which can be obtained through fish oil supplements, according to MedlinePlus.


Thusgaard, M., Christensen, J. H., Morn, B., Andersen, T. S., Vige, R., Arildsen, H., Schmidt, E. B., and Nielsen, H. Effect of fish oil (n-3 polyunsaturated fatty acids) on plasma lipids, lipoproteins and inflammatory markers in HIV-infected patients treated with antiretroviral therapy: a randomized, double-blind, placebo-controlled study. Scand.J.Infect.Dis. 2009;41(10):760-766. View abstract.
Causing unsafe conditions. Fish oil may increase the risk of bleeding, which can lead to an unsafe condition. Excessive bleeding inside the body may also lead to conditions such as ulcers or liver disease which could be quite dangerous. Be aware of the signs and symptoms of this condition such as bruising easily or nosebleeds which could be a sign that you are developing this condition. If you begin to bleed more easily than usual then you should reduce the amount of fish oil you take regularly to reduce this condition.
36. Marchioli R, Barzi F, Bomba E, Chieffo C, Di Gregorio D, Di Mascio R, Franzosi MG, Geraci E, Levantesi G, Maggioni AP, et al. Early protection against sudden death by n-3 polyunsaturated fatty acids after myocardial infarction: time-course analysis of the results of the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI)-Prevenzione. Circulation. 2002;105:1897–903. [PubMed]

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Evidence suggests that omega−3 fatty acids modestly lower blood pressure (systolic and diastolic) in people with hypertension and in people with normal blood pressure.[25] Some evidence suggests that people with certain circulatory problems, such as varicose veins, may benefit from the consumption of EPA and DHA, which may stimulate blood circulation and increase the breakdown of fibrin, a protein involved in blood clotting and scar formation.[26][27] Omega−3 fatty acids reduce blood triglyceride levels but do not significantly change the level of LDL cholesterol or HDL cholesterol in the blood.[28][29] The American Heart Association position (2011) is that borderline elevated triglycerides, defined as 150–199 mg/dL, can be lowered by 0.5-1.0 grams of EPA and DHA per day; high triglycerides 200–499 mg/dL benefit from 1-2 g/day; and >500 mg/dL be treated under a physician's supervision with 2-4 g/day using a prescription product.[30]

Fish oil is effective in reducing inflammation in the blood and tissues. Regular consumption of fish oil supplements, tablets, pills, and capsules is helpful to those who suffer from chronic inflammatory diseases. Fish oil is effective in treating gastrointestinal disorders, Celiac disease, short bowel syndrome and inflammatory bowel disease (IBD) including Crohn’s Disease and ulcerative colitis, which are both typical disorders of the intestine. Patients suffering from Crohn’s disease often find it difficult to absorb vitamins, fats, and essential supplements. Fish oil supplements are an effective diet for such patients.


In general, most health organizations agree 250–500 milligrams of EPA and DHA combined each day is a reasonable amount to support healthy individuals. However, people with heart problems (or those with a high risk of heart disease), depression, anxiety and cancer (and possibly more conditions) may benefit from higher doses — up to 4,000 milligrams per day for some heart-related conditions. (5)
If we want to deliver the benefits associated with EPA therapeutically, it is essential to optimise digestion and uptake. If we take EPA and DHA in their natural 1.5:1 ratio, it’s an uphill struggle for EPA because we know that DHA is more effectively absorbed and assimilated into cells. Delivering the benefits of EPA (for example, for cognitive function, mood and depression, inflammation regulation, heart health, skin health and so on), requires doses of EPA in excess of DHA, which determines the type of benefits obtained and the degree of the beneficial outcomes. The higher the ratio of EPA to DHA (meaning higher doses of EPA in relation to DHA), the more likely that EPA will be digested and absorbed, ready to meet the body’s high demands for this important nutrient.

De Truchis, P., Kirstetter, M., Perier, A., Meunier, C., Zucman, D., Force, G., Doll, J., Katlama, C., Rozenbaum, W., Masson, H., Gardette, J., and Melchior, J. C. Reduction in triglyceride level with N-3 polyunsaturated fatty acids in HIV-infected patients taking potent antiretroviral therapy: a randomized prospective study. J.Acquir.Immune.Defic.Syndr. 3-1-2007;44(3):278-285. View abstract.
High levels of the oils in blood samples were linked with a 71 per cent increased risk of developing an aggressive and dangerous form of prostate cancer, according to the research. That study, if I recall correctly, mentioned concern about men eating fish more than a certain number of times a week having a 54% increased risk of developing prostate cancer.
Hamazaki, K., Syafruddin, D., Tunru, I. S., Azwir, M. F., Asih, P. B., Sawazaki, S., and Hamazaki, T. The effects of docosahexaenoic acid-rich fish oil on behavior, school attendance rate and malaria infection in school children--a double-blind, randomized, placebo-controlled trial in Lampung, Indonesia. Asia Pac.J Clin Nutr 2008;17(2):258-263. View abstract.

A 2012 study involved children from 6 to 12 years of age with ADHD who were being treated with methylphenidate and standard behavior therapy for more than six months. The parents of these children reported no improvement in behavior and academic learning using these standard treatments. The researchers randomly gave some of the children an omega-3 and omega-6 acid supplementation or a placebo. They found “statistically significant improvement” for the omega group in the following categories: restlessness, aggressiveness, completing work and academic performance. (5)


It exists in nature in three forms, one derived from land plants and two derived from marine sources. In the body, omega-3 is highly concentrated in the brain; it is critical to the formation and maintenance of nerve cell membranes. Research shows that in the nervous system, omega-3s foster the development of brain circuitry and the processing of information. They also play important roles in stabilizing mood and staving off cognitive decline. Low levels of omega-3s are linked to poor memory and depression. Omega-3 fats are also critical for the formation of anti-inflammatory molecules in the body.
In a 2009 joint study by the USDA and researchers at Clemson University in South Carolina, grass-fed beef was compared with grain-finished beef. The researchers found that grass-finished beef is higher in moisture content, 42.5% lower total lipid content, 54% lower in total fatty acids, 54% higher in beta-carotene, 288% higher in vitamin E (alpha-tocopherol), higher in the B-vitamins thiamin and riboflavin, higher in the minerals calcium, magnesium, and potassium, 193% higher in total omega−3s, 117% higher in CLA (cis-9, trans-11 octadecenoic acid, a cojugated linoleic acid, which is a potential cancer fighter), 90% higher in vaccenic acid (which can be transformed into CLA), lower in the saturated fats linked with heart disease, and has a healthier ratio of omega−6 to omega−3 fatty acids (1.65 vs 4.84). Protein and cholesterol content were equal.[86]
Full citation: Abdelhamid AS, Brown TJ, Brainard JS, Biswas P, Thorpe GC, Moore HJ, Deane KHO, AlAbdulghafoor FK, Summerbell CD, Worthington HV, Song F, Hooper L. Omega 3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database of Systematic Reviews 2018, Issue 7. Art. No.: CD003177. DOI: 10.1002/14651858.CD003177.pub3.
Dyerberg, J., Eskesen, D. C., Andersen, P. W., Astrup, A., Buemann, B., Christensen, J. H., Clausen, P., Rasmussen, B. F., Schmidt, E. B., Tholstrup, T., Toft, E., Toubro, S., and Stender, S. Effects of trans- and n-3 unsaturated fatty acids on cardiovascular risk markers in healthy males. An 8 weeks dietary intervention study. Eur.J.Clin.Nutr. 2004;58(7):1062-1070. View abstract.
Five studies with 7 data sets recruited participants without specific clinical conditions.36,47,51,55,60 The main results revealed that there was no significant difference in the association of treatment with reduced anxiety symptoms between patients receiving omega-3 PUFA treatment and those not receiving it (k, 5; Hedges g, –0.008; 95% CI, –0.266 to 0.250; P = .95) (Figure 3A). Fourteen studies with 14 data sets recruited participants with specific clinical diagnoses.33-35,48-50,52-54,56-59,61 The main results revealed a significantly greater association of treatment with reduced anxiety symptoms in patients receiving omega-3 PUFA treatment than in those not receiving it (k, 14; Hedges g, 0.512; 95% CI, 0.119-0.906; P = .01) (Figure 3A). Furthermore, according to the interaction test, the association of omega-3 PUFA treatment with reduced anxiety symptoms was significantly stronger in subgroups with specific clinical diagnoses than in subgroups without specific clinical conditions (P = .03).
Second, quality matters. It is important to purchase fish oil from a reputable manufacturer that follows Good Manufacturing Practices (GMPs) and takes the necessary steps to purify the oil. In choosing a brand like Nature Made®, the #1 Pharmacist Recommended Omega-3/Fish Oil Brand*, you can rest assured knowing Nature Made has a strong commitment to making quality supplements so you can experience the benefits of fish oil.

The GISSI-Heart Failure trial was the first blinded, randomized trial to assess the efficacy of fish oil supplements in patients with heart failure.51 The trial enrolled 7046 subjects with heart failure; 60% with New York Heart Association class II symptoms and 40% with a history of MI. The majority of patients were on a standard heart failure regimen, including angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers, and spironolactone, but only 22% were on a statin. At an average of 3.9 years, the coprimary end points of death and death or hospital admission for cardiovascular reasons were reduced by approximately 9% with fish oil supplementation. Sudden cardiac death, a secondary end-point, showed a statistically nonsignificant relative risk reduction of 7% with fish oil. There was also a reduction in 2 other arrhythmia-related secondary end-points: first hospitalization for ventricular arrhythmia and presumed arrhythmic death.
Khandelwal, S., Demonty, I., Jeemon, P., Lakshmy, R., Mukherjee, R., Gupta, R., Snehi, U., Niveditha, D., Singh, Y., van der Knaap, H. C., Passi, S. J., Prabhakaran, D., and Reddy, K. S. Independent and interactive effects of plant sterols and fish oil n-3 long-chain polyunsaturated fatty acids on the plasma lipid profile of mildly hyperlipidaemic Indian adults. Br.J.Nutr. 2009;102(5):722-732. View abstract.
Growing up, Joe was plagued with a myriad of health issues such as gut problems, autoimmune issues, chronic fatigue, brain fog, insomnia, and general inflammation. Both conventional and alternative doctors weren’t able to help him, so he decided to fix himself. With lots of health questions and few satisfying answers, Joe decided to read every research paper he could get his hands on and conduct thousands of experiments on his own body in order to fix his health issues. Joe started SelfHacked in late 2013 when he successfully fixed all of his issues, and now it gets millions of readers a month looking to educate themselves about how they can improve their health. Joe is now a thriving author, speaker, and serial entrepreneur, founding SelfDecode & LabTestAnalyzer.
The chemical structures of EPA and DHA are very similar and they compete for uptake and processing resources. During digestion, the triglyceride molecules in standard fish oil are broken down into a mono glycerol and two free fatty acids, small enough to be absorbed into cells of the gut lining. More often than not, DHA is the fatty acid that remains attached to the glycerol backbone, meaning in essence that DHA gets a ‘free pass’ into the gut, while the remaining free fatty acids (more often EPA) must reattach onto a glycerol molecule or risk being oxidised and used as fuel. The implication of this is that DHA levels in our cells are often concentrated at the expense of EPA after absorption when taking EPA and DHA in the standard ratio of 1.5 to 1.
In our analysis, most of the included studies showed a positive Hedges g toward a beneficial effect of omega-3 PUFAs in anxiety reduction, although not all findings were statistically significant. However, after merging of these effect sizes from all of the included studies, the main result showed significant findings in our meta-analysis. Despite the significant heterogeneity, no significant publication bias was found among these 19 studies.
Growing up, Joe was plagued with a myriad of health issues such as gut problems, autoimmune issues, chronic fatigue, brain fog, insomnia, and general inflammation. Both conventional and alternative doctors weren’t able to help him, so he decided to fix himself. With lots of health questions and few satisfying answers, Joe decided to read every research paper he could get his hands on and conduct thousands of experiments on his own body in order to fix his health issues. Joe started SelfHacked in late 2013 when he successfully fixed all of his issues, and now it gets millions of readers a month looking to educate themselves about how they can improve their health. Joe is now a thriving author, speaker, and serial entrepreneur, founding SelfDecode & LabTestAnalyzer.
EPA, which is eicosapentaenoic acid, and DHA, which is docosahexaenoic acid, are two types of omega-3 fatty acids that are most commonly found in seafood. These polyunsaturated fats are known to have preventative health benefits and have been studied for their role in treating certain chronic conditions. In addition to dietary sources, certain supplements such as fish oil, are also rich in EPA and DHA.
Hamazaki, K., Syafruddin, D., Tunru, I. S., Azwir, M. F., Asih, P. B., Sawazaki, S., and Hamazaki, T. The effects of docosahexaenoic acid-rich fish oil on behavior, school attendance rate and malaria infection in school children--a double-blind, randomized, placebo-controlled trial in Lampung, Indonesia. Asia Pac.J Clin Nutr 2008;17(2):258-263. View abstract.
There are three types of omega-3 fatty acids, which include EPA, DHA and ALA, which is alpha-linoleic acid. Although EPA and DHA are found to have high amounts from animal sources, ALA is found in rich concentrations in plant sources, including certain vegetable oils and flaxseeds, although fatty fish and shellfish are the best sources of EPA and DHA, according to the National Center for Complementary and Alternative Medicine. Examples of these fatty fish and shellfish include salmon, tuna, trout, crab, oysters and mussels.
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.
Jatoi, A., Rowland, K., Loprinzi, C. L., Sloan, J. A., Dakhil, S. R., MacDonald, N., Gagnon, B., Novotny, P. J., Mailliard, J. A., Bushey, T. I., Nair, S., and Christensen, B. An eicosapentaenoic acid supplement versus megestrol acetate versus both for patients with cancer-associated wasting: a North Central Cancer Treatment Group and National Cancer Institute of Canada collaborative effort. J.Clin.Oncol. 6-15-2004;22(12):2469-2476. View abstract.
After the age of five, the development of the brain and CNS starts to reduce and the body’s need for DHA reduces. This is a good time to increase EPA in the diet, as studies show that EPA can help with childhood behaviour and academic performance, as well as focus, attention and reducing aggression. Dry skin conditions, asthma and allergies are also common in children and good levels of EPA at this time can help reduce the inflammation associated with these issues.

High triglycerides. Research suggests that fish oil from supplements and food sources can reduce triglyceride levels. The effects of fish oil appear to be the greatest in people who have very high triglyceride levels. Also the amount of fish oil consumed seems to directly affect how much triglyceride levels are reduced. One particular fish oil supplement called Lovaza has been approved by the FDA to lower triglycerides. A one-gram capsule of Lovaza contains 465 milligrams of EPA and 375 milligrams of DHA. But, a small study suggests that taking fish oil daily for 8 weeks might not reduce triglycerides in adolescents.


During pregnancy and breastfeeding, eating 8 to 12 ounces per week of fish and other seafood may improve your baby’s health. However, it is important to choose fish that are higher in EPA and DHA and lower in mercury. Examples are salmon, herring, sardines, and trout. It is not clear whether taking dietary supplements containing EPA and DHA during pregnancy or breastfeeding affects a baby’s health or development. However, some studies show that taking these supplements may slightly increase a baby’s weight at birth and the length of time the baby is in the womb, both of which may be beneficial. Breast milk contains DHA. Most commercial infant formulas also contain DHA.
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]
Foods such as meat, eggs, fish and nuts contain omega-3 and omega-6 fatty acids, which the body converts into endocannabinoids – cannabinoids that the body produces naturally, said Aditi Das, a University of Illinois professor of comparative biosciences and biochemistry, who led the study. Cannabinoids in marijuana and endocannabinoids produced in the body can support the body’s immune system and therefore are attractive targets for the development of anti-inflammatory therapeutics, she said.
Jump up ^ Naliwaiko, K.; Araújo, R.L.F.; Da Fonseca, R.V.; Castilho, J.C.; Andreatini, R.; Bellissimo, M.I.; Oliveira, B.H.; Martins, E.F.; Curi, R.; Fernandes, L.C.; Ferraz, A.C. (2004). "Effects of Fish Oil on the Central Nervous System: A New Potential Antidepressant?". Nutritional Neuroscience. 7 (2): 91–99. doi:10.1080/10284150410001704525. PMID 15279495.
To our knowledge, this is the first systematic review and meta-analysis to examine the anxiolytic effects of omega-3 PUFAs in individuals with anxiety symptoms. The overall findings revealed modest anxiolytic effects of omega-3 PUFAs in individuals with various neuropsychiatric or major physical illnesses. Although participants and diagnoses were heterogeneous, the main finding of this meta-analysis was that omega-3 PUFAs were associated with significant reduction in anxiety symptoms compared with controls; this effect persisted vs placebo controls. Furthermore, the association of treatment with reduced anxiety symptoms of omega-3 PUFA were significantly higher in subgroups with specific clinical diagnoses than in subgroups without clinical conditions.
Several small studies have shown that combination therapy with fish oil and HMG CoA reductase inhibitors is safe.56–61 The largest trial to date, the JELIS trial,32 was an open label trial of 18,645 Japanese adults with hypercholesterolemia who were randomized to a standard statin regimen or a fish oil formulation containing 1.8 g of EPA added to a statin medication. The cohort was made up mostly of postmenopausal, nonobese women with a 15% to 20% incidence of diabetes, tobacco use, or CAD. The primary outcome of any major cardiovascular event, at a mean of 4.6 years, was moderately reduced by a relative risk reduction of 26%. Both unstable angina and nonfatal MI were reduced, but no change was seen in sudden death. Overall, the findings were remarkable because at baseline approximately 90% of Japanese consumed at least 900 mg of EPA and DHA per day.62 The rates of cancer, joint pain, lumbar pain, or muscle pain were similar in the 2 groups. There was a similar rate of increase in measures of creatine phosphokinase, but more patients had an increase in aspartate aminotransferase levels (0.6% vs. 0.4%) in the fish oil group. The rate of bleeding was 1.1% in the fish oil combination group versus 0.6% in the HMG–CoA reductase inhibitor group.

The systematic review suggests that eating more ALA through food or supplements probably has little or no effect on cardiovascular deaths or deaths from any cause. However, eating more ALA probably reduces the risk of heart irregularities from 3.3 to 2.6%. The review team found that reductions in cardiovascular events with ALA were so small that about 1000 people would need to increase consumption of ALA for one of them to benefit. Similar results were found for cardiovascular death. They did not find enough data from the studies to be able to measure the risk of bleeding or blood clots from using ALA.


Today the only Food and Drug Administration (FDA)-approved form of dietary omega-3 FA supplement is Lovaza (omega-3-acid ethyl esters; GlaxoSmithKline), which contains 375 mg of DHA and 465 mg of EPA per 1 g capsule. The myriad of dietary supplements of fish oil, including Kosher capsules, vary from comparable content to insignificant amounts, and for the most part can include other fats and cholesterols. In comparison, to achieve approximately 1 g of EPA and DHA in a meal, 12 ounces of canned light tuna, 2 to 3 ounces of sardines, 1.5 to 2.5 ounces of farmed Atlantic salmon, or 20 ounces of farmed catfish must be consumed (Table 1).65 Unfortunately, potentially high levels of harmful pollutants offset this source of omega-3 FA. The FDA action level for unacceptably high mercury content in fish is 1.0 μg/g. The mercury level in most fish is at or below 0.1 μg/g, but tilefish, swordfish, and king mackerel have high levels of mercury. The majority of fish species also contain <100 ng/g of polychlorinated biphenyls, which is below the FDA action level of 2000 ng/g. Dioxins, which do not have FDA action levels, are present in the majority of marine life.66

If we want to deliver the benefits associated with EPA therapeutically, it is essential to optimise digestion and uptake. If we take EPA and DHA in their natural 1.5:1 ratio, it’s an uphill struggle for EPA because we know that DHA is more effectively absorbed and assimilated into cells. Delivering the benefits of EPA (for example, for cognitive function, mood and depression, inflammation regulation, heart health, skin health and so on), requires doses of EPA in excess of DHA, which determines the type of benefits obtained and the degree of the beneficial outcomes. The higher the ratio of EPA to DHA (meaning higher doses of EPA in relation to DHA), the more likely that EPA will be digested and absorbed, ready to meet the body’s high demands for this important nutrient.
Recent studies have shown that the consumption of fish oil (or, more specifically, the omega-3 fatty acids found in fish oil) can improve fertility in both men and women. DHA, which is a byproduct of omega-3 fatty acids, plays a key role in the mobility of sperm and health of sperm in men. Low blood levels of DHA have been linked to decreased fertility. Animal studies have found that the DHA in fish is vital to changing dysfunctional round-headed sperm into strong swimmers with cone-shaped heads packed with egg-opening proteins. (29)
For several years now, the fish oil and Alzheimer’s disease connection has been studied with consistent results. The essential fatty acids vital for brain function that are found in fish oil can not only slow cognitive decline, but can help prevent brain atrophy in older adults. A study published in the FASEB Journal looked at the health effects of four- to 17-month dietary supplementation with omega-3 fatty acids and antioxidants. The findings once again confirm the potential for fish oil to be used as a weapon to fend off the onset of cognitive decline and Alzheimer’s disease. (8)
Some research indicates that people who eat more seafood may have a reduced risk of cognitive decline. However, omega-3 supplements haven’t been shown to help prevent cognitive impairment or Alzheimer’s disease or to improve symptoms of these conditions. For example, a large NIH-sponsored study completed in 2015 indicated that taking EPA and DHA supplements did not slow cognitive decline in older adults. The people studied were participants in a larger eye disease study, and all of them had age-related macular degeneration (AMD). 
The American Heart Association (AHA) recommends that everyone eats fish (particularly fatty, coldwater fish) at least twice a week. Salmon, mackerel, herring, sardines, lake trout, and tuna are especially high in omega-3 fatty acids. While foods are your best bet for getting omega-3s in your diet, fish oil supplements are also available for those who do not like fish. The heart-healthy benefits of regular doses of fish oil supplements are unclear, so talk to your doctor to see if they're right for you. If you have heart disease or high triglyceride levels, you may need even more omega-3 fatty acids. Ask your doctor if you should take higher doses of fish oil supplements to get the omega-3s you need.

A 2009 metastudy found that patients taking omega-3 supplements with a higher EPA:DHA ratio experienced fewer depressive symptoms. The studies provided evidence that EPA may be more efficacious than DHA in treating depression. However, this metastudy concluded that due to the identified limitations of the included studies, larger, randomized trials are needed to confirm these findings.[40]


For several years now, the fish oil and Alzheimer’s disease connection has been studied with consistent results. The essential fatty acids vital for brain function that are found in fish oil can not only slow cognitive decline, but can help prevent brain atrophy in older adults. A study published in the FASEB Journal looked at the health effects of four- to 17-month dietary supplementation with omega-3 fatty acids and antioxidants. The findings once again confirm the potential for fish oil to be used as a weapon to fend off the onset of cognitive decline and Alzheimer’s disease. (8)

Depression. There is inconsistent evidence on the effect of taking fish oil for depression. Some research shows that taking fish oil along with an antidepressant might help improve symptoms in some people. Other research shows that taking fish oil does not improve depression symptoms. The conflicting results may be due to the amount of EPA and DHA in the supplement or the severity of depression before treatment.
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