Uses

Attention-Deficit Hyperactivity Disorder (ADHD)

Because children need omega-3 fatty acids for their brains to develop properly, researchers have looked at whether fish oil might reduce ADHD symptoms. So far, results have been mixed. One study showed fish oil might help, but many people dropped out of the study before it was done.

Depression

Some studies show that fish oil reduces symptoms of depression. Other studies suggest it may be a kind of EPA known as ethyl-EPA (and not DHA) that reduces symptoms.

Heart Disease

Fish oil seems to help people who already have heart disease. It also may lower the risk for developing heart disease. Omega-3 fatty acids found in fish oil help lower triglycerides and blood pressure, reduce the risk of blood clots, improve the health of arteries and reduce the amount of arterial plaque, which narrows arteries, and causes heart disease.

The American Heart Association (AHA) recommends eating fish, particularly fatty fish, at least 2 times a week. Fatty fish include salmon, herring, lake trout, sardines, and albacore tuna. People with existing heart disease may need fish oil supplements in addition to adding more fish to their diet. Ask your doctor if fish oil supplements would be right for you.

Rheumatoid Arthritis

Several small studies indicate that fish oil may help reduce symptoms and inflammation from rheumatoid arthritis. However, it does not stop joint damage from getting worse.

Menopause

One study found that EPA reduced the number of hot flashes by 1.58 per day in menopausal women. It did not decrease the severity of the hot flashes, however.

Menstrual Pain

Fish oil appears to reduce the pain of menstrual cramps when taken on a regular basis (not just when menstruating).

Raynaud Syndrome

Several studies show that high doses (12 g) of fish oil can make fingers and toes less sensitive to cold when people have Raynaud syndrome. Doses this high should be taken only under a doctor's supervision.

Lupus

Two small studies suggested that fish oil reduced fatigue and joint pain from lupus.

Other Conditions

Omega-3 fatty acids, including EPA, may also have positive effects on lung and kidney diseases, type 2 diabetes, obesity, ulcerative colitis, Crohn disease, anorexia nervosa, burns, osteoarthritis, osteoporosis, and early stages of colorectal cancer.

Dietary Sources

EPA is found in cold-water fatty fish, including salmon, tuna, mackerel, sardines, shellfish, and herring. Although some of these fish contain low levels of mercury, according to the Food and Drug Administration (FDA) eating several servings of fish each week poses no risk to healthy people and offers many health benefits.

Women who are pregnant or planning to become pregnant should avoid Atlantic mackerel, shark, swordfish, and tilefish, and eat less than 6 oz. of white albacore tuna per week. These fish tend to be higher in mercury.

High-quality fish oil supplements made by manufacturers who test for mercury and other toxins do not have the same risk of mercury contamination. Read labels carefully and check for purity, or ask your doctor to help you find the best quality fish oil supplement.

Available Forms

EPA is available in fish oil capsules, along with DHA (docosahexaenoic acid). Some commercial products may also contain vitamin E to maintain freshness.

How to Take It

Pediatric

• Babies who are breastfed should get enough EPA if their mother is getting enough EPA in her diet.

Adult

• The adequate daily intake of EPA for adults should be at least 220 mg per day.
• In the diet: 2 to 3 servings of fatty fish per week, which is the same as about 1,250 mg EPA and DHA per day.
• Fish oil supplements: 3,000 to 4,000 mg standardized fish oils per day. Read the label to check levels of DHA and EPA, which are not the same as mg of fish oil. People who take blood-thinning medication, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin, or people who have hemophilia, should ask their doctors what is a safe dose.

Some fish oil supplements also contain vitamin E for freshness. Check the label to see whether the product needs to be refrigerated. DO NOT use products beyond their expiration date.

Precautions

Fish oil capsules have both DHA and EPA. DO NOT give supplements with EPA to a child unless your pediatrician tells you to because they upset the healthy balance between DHA and EPA during early development. Pregnant women should talk to their doctor before taking fish oil supplements.

Fish oil capsules may cause minor side effects, such as loose stools, stomach upset, and belching.

They also may raise the risk of bleeding. If you take blood-thinning medication, talk to your doctor before taking fish oil.

Possible Interactions

Blood pressure medication: Fish oil may lower blood pressure, so it could make the effects of prescription blood pressure medication stronger.

Blood-thinners (anticoagulants and antiplatelets): EPA in fish oil supplements may increase bleeding time, so fish oil could make these drugs act stronger. The same does not seem to be true of DHA alone. Blood thinners include warfarin (Coumadin), clopidogrel (Plavix), and aspirin.

Diabetes medications: Theoretically, fish oil supplements may lower blood sugar levels and could make diabetes drugs act stronger. If you have diabetes, talk to your doctor before taking fish oil.

Aspirin: Taken with aspirin, fish oil may help treat some forms of heart disease. However, this combination may also increase the risk of bleeding. Talk to your doctor to see if this combination is right for you.

Cyclosporine: Omega-3 fatty acids may reduce some of the side effects of cyclosporine, which is often used to stop rejection in transplant recipients. Talk to your doctor before adding any new herbs or supplements to the medication you already take.

Supporting Research

Amiano P, Machon M, Dorronsoro M, et al. Intake of total omega-3 fatty acids, eicosapentaenoic acid and docosahexaenoic acid and risk of coronary heart disease in the Spanish EPIC cohort study. Nutr Metab Cardiovasc Dis. 2014;24(3):321-7.

Angerer P, von Schacky C. n-3 polyunsaturated fatty acids and the cardiovascular system. Curr Opin Lipidol. 2000;11(1):57-63.

Aronson WJ, Glaspy JA, Reddy ST, Reese D, Heber D, Bagga D. Modulation of omega-3/omega-6 polyunsaturated ratios with dietary fish oils in men with prostate cancer. Urology. 2001;58(2):283-288.

Belluzzi A, Boschi S, Brignola C, Munarini A, Cariani C, Miglio F. Polyunsaturated fatty acids and inflammatory bowel disease. Am J Clin Nutr. 2000;71(suppl):339S-342S.

Boelsma E, Hendriks HF. Roza L. Nutritional skin care: health effects of micronutrients and fatty acids. Am J Clin Nutr. 2001;73(5):853-864.

Bruinsma KA, Taren DL. Dieting, essential fatty acid intake, and depression. Nutrition Rev. 2000;58(4):98-108.

Burgess J, Stevens L, Zhang W, Peck L. Long-chain polyunsaturated fatty acids in children with attention-deficit hyperactivity disorder. Am J Clin Nutr. 2000;71(suppl):327S-330S.

Calder PC. n-3 polyunsaturated fatty acids, inflammation and immunity: pouring oil on troubled waters or another fishy tale? Nut Res. 2001;21:309-341.

Caron MF, White CM. Evaluation of the antihyperlipidemic properties of dietary supplements. Pharmacotherapy. 2001;21(4):481-487.

Cho E, Hung S, Willet WC, Spiegelman D, Rimm EB, Seddon JM, et al. Prospective study of dietary fat and the risk of age-related macular degeneration. Am J Clin Nutr. 2001;73(2):209-218.

Christensen JH, Skou HA, Fog L, Hansen V, Vesterlund T, Dyerberg J, Toft E, Schmidt EB. Marine n-3 fatty acids, wine intake, and heart rate variability in patients referred for coronary angiography. Circulation. 2001;103:623-625.

Cicero AF, Derosa G, Di Gregori V, Bove M, Gaddi AV, Borghi C. Omega 3 polyunsaturated fatty acids supplementation and blood pressure levels in hypertriglyceridemic patients with untreated normal-high blood pressure and with or without metabolic syndrome: a retrospective study. Clin Exp Hypertens. 2010 Jan;32(2):137-44.

Clark WF, Kortas C, Heidenheim AP, Garland J, Spanner E, Parbtani A. Flaxseed in lupus nephritis: a two-year nonplacebo-controlled crossover study. J Am Coll Nutr. 2001;20(2 Suppl):143-148.

Curtis CL, Hughes CE, Flannery CR, Little CB, Harwood JL, Caterson B. N-3 fatty acids specifically modulate catabolic factors involved in articular cartilage degradation. J Biol Chem. 2000;275(2):721-724.

Dewailly E, Blanchet C, Lemieux S, et al. n-3 fatty acids and cardiovascular disease risk factors among the Inuit of Nunavik. Am J Clin Nutr. 2001;74(4):464-473.

Dichi I, Frenhane P, Dichi JB, Correa CR, Angeleli AY, Bicudo MH, et al. Comparison of omega-3 fatty acids and sulfasalazine in ulcerative colitis. Nutrition. 2000;16:87-90.

Fatty fish consumption and ischemic heart disease mortality in older adults: The cardiovascular heart study. Presented at the American Heart Association's 41st annual conference on cardiovascular disease epidemiology and prevention. AHA. 2001.

Fenton WS, Dicerson F, Boronow J, et al. A placebo controlled trial of omega-3 fatty acid (ethyl eicosapentaenoic acid) supplementation for residual symptoms and cognitive impairment in schizophrenia. Am J Psychiatry. 2001;158(12):2071-2074.

Freeman VL, Meydani M, Yong S, Pyle J, Flanigan RC, Waters WB, Wojcik EM. Prostatic levels of fatty acids and the histopathology of localized prostate cancer. J Urol. 2000;164(6):2168-2172.

Frieri G, Pimpo MT, Palombieri A, Melideo D, Marcheggiano A, Caprilli R, et al. Polyunsaturated fatty acid dietary supplementation: an adjuvant approach to treatment of Helicobacter pylori infection. Nut Res. 2000;20(7):907-916.

Geerling BJ, Badart-Smook A, van Deursen C, et al. Nutritional supplementation with N-3 fatty acids and antioxidants in patients with Crohn's disease in remission: effects on antioxidant status and fatty acid profile. Inflamm Bowel Dis. 2000;6(2):77-84.

Goodfellow J, Bellamy MF, Ramsey MW, Jones CJ, Lewis MJ. Dietary supplementation with marine omega-3 fatty acids improve systemic large artery endothelial function in subjects with hypercholesterolemia. J Am Coll Cardiol. 2000;35(2):265-270.

Halpern G-M. Anti-inflammatory effects of a stabilized lipid extract of Perna canaliculus (Lyprinol). Allerg Immunol (Paris). 2000;32(7):272-278.

Harper CR, Jacobson TA. The fats of life: the role of omega-3 fatty acids in the prevention of coronary heart disease. Arch Intern Med. 2001;161(18):2185-2192.

Iso H, Rexrode KM, Stampfer MJ, Manson JE, Colditz GA, Speizer FE et al. Intake of fish and omega-3 fatty acids and risk of stroke in women. JAMA. 2001;285(3):304-312.

Jacobson TA. Role of n-3 fatty acids in the treatment of hypertriglyceridemia and cardiovascular disease. Am J Clin Nutr. 2008 Jun;87(6):1981S-90S.

Juhl A, Marniemi J, Huupponen R, Virtanen A, Rastas M, Ronnemaa T. Effects of diet and simvistatin on serum lipids, insulin, and antioxidants in hypercholesterolemic men; a randomized controlled trial. JAMA. 2002;2887(5):598-605.

Krauss RM, Eckel RH, Howard B, et al. AHA Scientific Statement: AHA Dietary guidelines Revision 2000: A statement for healthcare professionals from the nutrition committee of the American Heart Association. Circulation. 2000;102(18):2284-2299.

Kremer JM. N-3 fatty acid supplements in rheumatoid arthritis. Am J Clin Nutr. 2000;(suppl 1):349S-351S.

Kris-Etherton P, Eckel RH, Howard BV, St. Jeor S, Bazzare TL. AHA Science Advisory: Lyon Diet Heart Study. Benefits of a Mediterranean-style, National Cholesterol Education Program/American Heart Association Step I Dietary Pattern on Cardiovascular Disease. Circulation. 2001;103:1823.

Kris-Etherton PM, Taylor DS, Yu-Poth S, et al. Polyunsaturated fatty acids in the food chain in the United States. Am J Clin Nutr. 2000;71(1 Suppl):179S-188S.

Kromhout D. Omega-3 fatty acids and coronary heart disease. The final verdict? Curr Opin Lipidol. 2012 Dec;23(6):554-9. doi: 10.1097/MOL.0b013e328359515f.

Leaf A. Historical overview of n-3 fatty acids and coronary heart disease. Am J Clin Nutr. 2008 Jun;87(6):1978S-80S.

Levy E, Rizwan Y, Thibault L, et al. Altered lipid profile, lipoprotein composition, and oxidant and antioxidant status in pediatric Crohn's disease. Am J Clin Nutr. 2000;71:807-815.

Lopez-Miranda J, Gomez P, Castro P, et al. Mediterranean diet improves low density lipoproteins' susceptibility to oxidative modifications. Med Clin (Barc) [in Spanish]. 2000;115(10):361-365.

Lucas M, Asselin G, Merette C, et al. Effects of ethyl-eicosapentaenoic acid omega-3 fatty acid supplementation on hot flashes and quality of life among middle-aged women: a double-blind, placebo-controlled, randomized clinical trial. Menopause. 2009;16:357-66.

Mabile L, Piolot A, Boulet L, Fortin LJ, Doyle N, Rodriquez C, et al. Moderate intake of omega-3 fatty acids is associated with stable erythrocyte resistance to oxidative stress in hypertriglyceridemic subjects. Am J Clin Nutr. 2001;7494):449-456.

Meydani M. Omega-3 fatty acids alter soluble markers of endothelial function in coronary heart disease patients. Nutr Rev. 2000;58(2 pt 1):56-59.

Miller PE, Van Elswyk M, Alexander DD. Long-chain omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid and blood pressure: a meta-analysis of randomized controlled trials. Am J Hypertens. 2014;27(7):885-96.

Montori V, Farmer A, Wollan PC, Dinneen SF. Fish oil supplementation in type 2 diabetes: a quantitative systematic review. Diabetes Care. 2000;23:1407-1415.

Mozaffari-Khosravi H, Yassini-Ardakani M, Karamati M, Shariati-Bafghi SE. Eicosapentaenoic acid versus docosahexaenoic acid in mild-to-moderate depression: a randomized, double-blind, placebo-controlled trial. Eur Neuropsychopharmacol . 2013;23(7):636-44.

Nagakura T, Matsuda S, Shichijyo K, Sugimoto H, Hata K. Dietary supplementation with fish oil rich in omega-3 polyunsaturated fatty acids in children with bronchial asthma. Eur Resp J. 2000;16(5):861-865.

Nannicini F, Sofi F, Avanzi G, Abbate R, Gensini GF. Alpha-linolenic acid and cardiovascular diseases omega-3 fatty acids beyond eicosapentaenoic acid and docosahexaenoic acid. Minerva Cardioangiol. 2006;54(4):431-42.

Newcomer LM, King IB, Wicklund KG, Stanford JL. The association of fatty acids with prostate cancer risk. Prostate. 2001;47(4):262-268.

Okamoto M, Misunobu F, Ashida K, et al. Effects of dietary supplementation with n-3 fatty acids compared with n-6 fatty acids on bronchial asthma. Int Med. 2000;39(2):107-111.

Okamoto M, Misunobu F, Ashida K, et al. Effects of perilla seed oil supplementation on leukotriene generation by leucocytes in patients with asthma associated with lipometabolism. Int Arch Allergy Immunol. 2000;122(2):137-142.

Oken E, Radesky JS, Wright RO, Bellinger DC, Amarasiriwardena CJ, Kleinman KP, et al. Maternal fish intake during pregnancy, blood mercury levels, and child cognition at age 3 years in a US cohort. Am J Epidemiol. 2008 May 15;167(10):1171-81.

Olsen SF, Secher NJ. Low consumption of seafood in early pregnancy as a risk factor for preterm delivery: prospective cohort study. BMJ. 2002;324(7335):447-451.

Puri B, Richardson AJ, Horrobin DF, et al. Eicosapentaenoic acid treatment in schizophrenia associated with symptom remission, normalisation of blood fatty acids, reduced neuronal membrane phospholipid turnover and structural brain changes. Int J Clin Pract. 2000;54(1):57-63.

Ras RT, Demonty I, Zebregs YE, Quadt JF, Olsson J, Trautwein EA. Low doses of eicosapentaenoic acid and docosahexaenoic acid from fish oil dose-dependently decrease serum triglyceride concentrations in the presence of plant sterols in hypercholesterolemic men and women. J Nutr. 2014;144(10):1564-70.

Richardson AJ, Puri BK. The potential role of fatty acids in attention-deficit/hyperactivity disorder. Prostaglandins Leukot Essent Fatty Acids. 2000;63(1/2):79-87.

Saravanan P, Davidson NC, Schmidt EB, Calder PC. Cardiovascular effects of marine omega-3 fatty acids. Lancet. 2010 Aug 14;376(9740):540-50. Review.

Schacky CV, Harris WS. Cardiovascular benefits of omega-3 fatty acids. Cardiovasc Res. 2006 Sep 1; [Epub ahead of print].

Seddon JM, Rosner B, Sperduto RD, Yannuzzi L, Haller JA, Blair NP, Willett W. Dietary fat and risk for advanced age-related macular degeneration. Arch Opthalmol. 2001;119(8):1191-1199.

Simopoulos AP. Human requirement for N-3 polyunsaturated fatty acids. Poult Sci. 2000;79(7):961-970.

Smith W, Mitchell P, Leeder SR. Dietary fat and fish intake and age-related maculopathy. Arch Opthamol. 2000;118(3):401-404.

Stampfer MJ, Hu FB, Manson JE, Rimm EB, Willett WC. Primary prevention of coronary heart disease in women through diet and lifestyle. N Engl J Med. 2000;343(1):16-22

Stark KD, Park EJ, Maines VA, et al. Effect of fish-oil concentrate on serum lipids in postmenopausal women receiving and not receiving hormone replacement therapy in a placebo-controlled, double blind trial. Am J Clin Nutr. 2000;72:389-394.

Sun Q, Ma J, Campos H, Rexrode KM, Albert CM, Mozaffarian D, Hu FB. Blood concentrations of individual long-chain n-3 fatty acids and risk of nonfatal myocardial infarction. Am J Clin Nutr. 2008 Jul;88(1):216-23.

Tang FY, Cho HJ, Pai MH, Chen YH. Concomitant supplementation of lycopene and eicosapentaenoic acid inhibits the proliferation of human colon cancer cells. J Nutr Biochem. 2008 Aug 15. [Epub ahead of print]

Terry P, Lichtenstein P, Feychting M, Ahlbom A, Wolk A. Fatty fish consumption and risk of prostate cancer. Lancet. 2001;357(9270):1764-1766.

Tsujikawa T, Satoh J, Uda K, Ihara T, Okamoto T, Araki Y, et al. Clinical importance of n-3 fatty acid-rich diet and nutritional education for the maintenance of remission in Crohn's disease. J Gastroenterol. 2000;35(2):99-104.

Zambón D, Sabate J, Munoz S, et al. Substituting walnuts for monounsaturated fat improves the serum lipid profile of hypercholesterolemic men and women. Ann Intern Med. 2000;132:538-546.

Zimmerman R, Radhakrishnan J, Valeri A, Appel G. Advances in the treatment of lupus nephritis. Ann Rev Med. 2001;52:63-78.