The omega-3 fatty acids EPA and DHA are valuable for one's health. They are used in the phospholipid bilipid layer of cell membranes to add flexibility. The body incorporates them in the linings of nerve cell membranes in the brain as well as in some other parts of the body.
EPA and DHA are most easily obtained from fatty fish, with somewhat lower amounts in virtually all seafood. They are also present in much smaller amounts in wild land animals and range-fed livestock. Testing has found that the average vegan is significantly more deficient than the average omnivore, although probably anyone not eating a pound of fish a week or taking a supplement is obtaining less than the optimum amount. Fish oil or microalgae oil supplements are simple ways of getting EPA and DHA and fish oil is very inexpensive. Fish oil also avoids mercury and organochlorines, toxins present in varying levels in whole fish.
EPA and DHA have many beneficial effects on many different diseases. Heart disease, cancers, Alzheimer's disease, psychiatric illness, arthritis, and allergies some of them. Between this page and all of its sub-pages listed above you can read many of the beneficial studies. I recommend that everyone eat a pound of seafood each week or take two to three fish oil capsules a day. I have found it cheapest at Osco's when the Osco brand has a two for one sale. Large containers are also very inexpensive at Walmart.
There are special half-sized capsules available for children who can't swallow the larger capsules. The cheapest I have found of the internet at www.iHerb.com. My children have tried several liquid fish oil preparations and none tasted good, but they all tasted better than cod liver oil. For patients with bad depression, I recommend three to four fish oil capsules per day in addition to any medicine they might need.
For vegetarians, there is DHA extracted from phytoplankton, the same source where fish get it. This is roughly 10 times more expensive than fish oil. The cheapest I have found also at iHerb.com. I personally think its worth the money. Flax seeds are very high in a shorter chain omega-3 fatty acid and the body is able to convert this into EPA and DHA although with considerable difficulty. While flax is a less desirable source, a fair number of studies have shown health benefits from flax for individuals not eating fish. Flax seeds can be obtained very cheaply, are good for at least several years, and do not need to be refrigerated. Flax oil is much more expensive, needs refrigeration, and deteriorates in several months. A teaspoon of flax seeds a day is probably good enough and can be added to breads or granola, sprinkled on cereal, or even eaten right off the spoon. I enjoy the texture they add to my homemade rolled wheat and rolled rye nut and raisin granola.
Omega-3 Fatty Acids (Fish Oil, etc.) Best for Lowering Mortality, Statins and Resins Help: In an analysis of 97 studies of lipid-lowering interventions covering 137,140 individuals in intervention and 138,976 individuals in control groups, compared with control groups, risk ratios for overall mortality were 0.87 for statins, 1.00 for fibrates, 0.84 for resins, 0.96 for niacin, 0.77 for omega-3 fatty acids, and 0.97 for diet. Effect of different antilipidemic agents and diets on mortality: a systematic review. Studer M, Briel M, et al. University Hospital Basel, Switzerland. Arch Intern Med. 2005 Apr 11;165(7):725-30.
Fish Oil May be Safer than Fish: Fish contain environmental toxins such as mercury, polychlorinated biphenyls, and organochlorine pesticides. In a study of 5 commercial fish oil brands, the levels of polychlorinated biphenyls and organochlorines were all below the detectable limit. Measurement of organochlorines in commercial over-the-counter fish oil preparations: implications for dietary and therapeutic recommendations for omega-3 fatty acids and a review of the literature. Melanson SF, Lewandrowski EL, et al. Harvard. Arch Pathol Lab Med. 2005 Jan;129(1):74-7.
Farmed Fish Not As Good: Not surprisingly, since the DHA contained in fish is manufactured by phytoplankton, wild fish are higher in DHA than farm raised fish. In five studies farmed fish had a higher fat content but the N-3 to N-6 fatty acid ratio is higher in the wild trout, salmon, and carp in the two studies reporting this data. R Bhopal, Newcastle, BMJ ’99;318:945. Farmed fish are routinely fed fish in order to get some omega-3 fatty acids since these are necessary for fish health. I have read that farm fish are fed three pounds of less valuable fish as fish meal to produce one pound of retail fish. Thus, taking fish oil capsules, which come from the low value fish or discarded parts of retail fish, actually minimizes the number of fish being killed.
Algae DHA Natrol $$: Pure DHA is available from Martek of Columbia, MD (www.martekbio.com). It is sold in drug stores under the brand of Neuromins DHA capsules available at Rite-Aid as well as others. Ordering by phone cost $25 for 60 capsules or 41 cents a capsule vs. 7 cents for fish oil capsules which actually contain more long chain fatty acids which can be converted to each other by the body. It is not available in a bottle as a liquid although it might have a better flavor than fish oil and be advantageous. It is apparently made from phytoplanton although the company says "microalgae."
Perilla but not Borage Oil Increase DHA-EPA in Rats: A study of safflower, borage, and perilla oil found perilla (high in ALA 18:3n-3) effective at decreasing AA and increasing EPA and DHA but not borage. Gu, Japan, Biosci Biotech Biochem 10/98;62:1917; Borage is high in GLA(18:3n-6) and did increase this and AA in rats. Has been found to decrease BP in Wistar rats sensitive to HBP. Engler, UCSF, PLEFA 7/98;59:11; Borage decreases omega-3 fatty acids in the body.
Decreases BP, Cholesterol, TG, Prevent Clots, & Anti-Inflammatory. If there is markedly decreased DHA availability, infants get smaller brains and vision difficulty. There is more DHA in brains of breast fed than in formula fed (Lancet 345:1463 ’95). Eating fish increases the DHA in breast milk. Breast milk DHA was found lowest in vegans. An NIAAA study found increased depression with an increased ratio of Omega-6:Omega-3 fatty acids. The human diet is thought to have been originally closer to 1:1, and is now 10-25:1 in most countries. Fatty acid deficiency symptoms are thirst, frequent urination, and dry hair and skin. 4/97 Nutr Sci News Michelle Badash
Body Fats Measured: The omega-6:omega-3 ratio in body fat in the U.S. is 18:1; in Japan where fish is consumed much more often than in the U.S., it is 5:1.
EPA and DHA Accumulate Fast At First: A study with normal volunteers found increases in red blood cell EPA/DHA levels was rapid the first two months and continued through the four months of intake. During three months of "washout," the levels fell slowly but by three months were only slightly above initial levels. Prisco U Florence, Am J Clin Nutr 6/96;63-925
Eskimos Very High Omega-3: For Eskimos, 14% of the fats in their diet are n-3 EPA and DHA vs. 3% in Denmark and 0.2% in U.S. They have low coronary heart disease and low serum cholesterol despite somewhat high cholesterol intake in fish, and high HDL cholesterol. Feskens, the Netherlands, Ann NY Acad Sci 6/14/93;683:9
Smoking Decreases DHA and AA: As the number of cigarettes smoked increases, the phospholipid content of DHA and AA decreases. Simon, SF VA, Am J Epidem 8/96, 144:325
Fish Oil Fewer Toxins than Fish: While research on populations actually consuming large amounts of ocean fish suggest that the mercury concerns are overblown, people consuming Great Lakes fish have more cancers. A new study of the five leading brands of fish oil capsules reports any toxins were non-detectable. Arch Pathol Lab Med. 2005;129:74-77
Fish Oil & Margarine Don’t Fit: Fish oil may benefit RA (Rheumatoid Arthritis) and psoriasis. In a 7 week study of males receiving 1.6 g EPA and 0.32 g DHA in fish oil, half stayed on diet high in linoleic acid by using margarine and polyunsaturated oil in cooking. Half used butter and olive oil which are low in linoleic. The incorporation of fish oil was better with the butter and olive oil diet. Linoleic polyunsaturated fats should be excluded to maximized benefit of fish oil. Leslie Cleland, Am J Clin Nutr 2/92;55:395-99
Fish Oil Margarine: A sunflower oil margarine with 13% fish oil increased EPA, DPA and DHA vs. a sunflower based margarine. Vitamin E was decreased. Nina Sorensen, Tech U Denmark, Am J Clin Nutr ’98;68:235-41. Study supported by MD Foods of Aarhus, Denmark. Margarine was 16% water 4 mg beta-carotene/kg color agent, 0.2g EDTA/kg, an antioxidant mix of propylgallate 20% and citric acid monoglyceride ester 80% at a rate of 0.04 mg/g.
EPA vs. DHA: 234 healthy men 36-56yo were treated with 3.6g/d DHA or EPA or placebo. The DHA group showed a 69% increase in DHA and a 27% increase in EPA by retroconversion. EPA group showed 297% increase in EPA but 15% decrease in DHA, suggesting lack of conversion of EPA to DHA. Both decreased triacylglycerols: 21% EPA 26% DHA. DHA increased the healthy HDL. EPA decreased total cholesterol. Grimsgaard, U Tromso, Am J Clin Nutr 9/97;66:649.
Benefit Not Decreased by Omega-6: Study reports that the benefits of fish oil were not diminished by presence of omega-6 fatty acids. Hwang, Louisiana State, Am J Clin Nutr 7/97;66:89
May Need More Vit E: London study found 9 males on fish oil supplement 2.1g DHA and .8g EPA for 6 wk had increased DHA and EPA in blood and decreased VLDL and TG and BP. Alpha-tocopherol (Vit E) fell fr 20 micromol/L to 10. May increase the need for antioxidant supplementation. T. Sanders. Br J Nutr 7/92;68:163-73.
Decreased Thrombomodulin & von Willebrand Factor: DB 41 hyperlipemic smokers with fish oil. Results may show improvement in endothelial dysfunction and incr E-selectin and vascular cell adhesion molecule-1 suggesting adverse effect on inflammation system. No effect from DB on Vit E, C, and beta-carotene simultaneously given in DB fashion. Seljeflot, Norway, Eur J Clin Invest 8/98;28:629
Greek Eggs Highest in DHA: Study comparing Greek eggs to eggs of chickens raised on fish meal or flax. Breast milk at 1 mo. Gives 250 mg LCPUFAs=.94 greek yolks, 1.6 flax yolks, 1.4 fish yolks, and 8.3 regular yolks. Simopolous, DC, @ Am J Clin Nutr 2/92:55:411; Also see Cherian, Lipids ’92;27:706 & 27:274; The LCPUFAs are incorporated preferentially in phosphatidylethanolamine over phosphatidylcholine by 7:1. ’91;Poult Sci 70:2467; @ Lipids 93;28:811; Kaminskas, Vopr Pitan 92’L 5-6):13. fed 20 DM pt 30g flax oil/d and only 6 obtained minor incorp of LCPUFAs into lipoprotein maybe due to low delta6-desatur activity. Recommends fish.
Soy Oil adds Stability to Fish Oil Paul Brown of Purdue U has shown that feeding fish with 6-18% fish oil combined with soy improved growth whereas fish oil without soy impaired growth.
Fish Oil Helps Lower BP: Thought lower BP and TG and VLDL and reduce platelet aggregation and suppress growth smooth-muscle cells in arterial walls. Univ Tromso study fish oil supplement lowers BP in P decr 4.4 mm Hg systolic, 3.2 mm Hg diastolic. TG and VLL also decreased 9% and increased in corn oil group 12%. Ingrid Toft, Annals Int Med 12/15/95;123:911-8.
Fish Oil No Benefit Diabetic Nephropathy: 36 IDDM pt rx 4.6g/d n-3 fish oil vs placebo for 1 year with no benefit fish oil. Rossing, Denmark, Diabetes Care 11/96;19:1214
Fish Oil Helps TG but Not Insulin Sensitivity: Very small 16 pt DB study 2.7g/d n-3 fish oil for 1 month then 1.7g/d four months lowered TG and VLDL without affect on insulin sensitivity and no loss of glucose control. Rivellese, Naples, Diabetes Care 11/96;19:1207.
Eskimos Hurt by Switching Away From Fish: Rapid increases in Eskimo diabetes linked to switch to store-bought food. Int J Circumpolar Health 4/99
Fish Oil Helped Teenagers: 21 teenagers given placebos for two months then half given 1080mg EPA and 720mg DHA and Vit E 1.5 mg for two months. Markedly decrease in symptoms in the treatment groups from score of 69 to 44 and no change in controls. Harel, Cincinnati, Am J Ob Gyn 4/96;174:1335-8
Dysmenorrhea Correlates with Low Intake n-3: Deutsch, Eur J Clin Nutr 95;49:508
Evening Primrose No Benefit PMS: 38 pt DB placebo crossed-over after three cycles. SK Khoo, U Queensland, Med J Aust 8/20/90;153:189-92
Evening Primrose No Benefit Menopause: 56 DB 2g/d 6 mo. Only change was a decr in night time flushes. BMJ 2/19/94;308-501-3
Evening Primrose Not Help Recurrent Breast Cyst: 200 with aspiration DB 6 caps /d 1 yr. Non-signif slight diff favoring evening. Mansel, Cardiff, Ann NY Acad Sci ’90;586:288-94
Emphysema & Cystic Fibrosis
Protects Against Emphysema & Bronchitis Development: Says other studies show helps RA and ulcerative colitis. U Minn study 8960 people, 55% former smokers, 45% current. Those eating four servings of fish/wk had half the risk of developing chronic bronchitis as those eating 0.5 serving or less. Only 1/3 the risk of emphysema. Four servings=480 mg EPA&DHA. Eyal Shahar, NEJM 7/28/94:331:228-33.
Helps Alleviate Cystic Fibrosis: U Sydney study 16 pt 12-26y0. Half received fish oil with 2.7g EPA/d vs. olive oil for 6 wk. Fish oil pt coughed up les sputum, breathing more easily (incr FEV and vital capacity) and felt better. Think modifying leukotriene B4, the main culprit of excessive inflam response to bacteria in CF. R Lawrence, Lancet 8/21/93;342:465-9.
Fish Oil Trend Decr Indomethacin Inflam: DB with healthy volunteers 8g/d n-3 fish oil vs placebo for 4 months. Betwee 12th and 16th week took indometh 50mg TID. No signif diff on Giscope in stomach or duod but strong trend p<.056 for benefit. Kremer, Albany, J Rheumotol 10/96;23:1770
Tend Toward Benefit: DB PC 37 adults with gingivitis induced by 21 days with brushing Rx with 8 day of 6g/d n-3 fish oil vs placebo. No significant differences although several trends in favorable direction. Campan, Toulouse, J Clin Periodontal 12/97;24:907-13
Fish Oil No Difference Lymphocyte Proliferation or Monocyte: DB study placebo vs. arginine vs. arginine+n-3 for 7 days before GI surgery. McCarter, Cornell, J Parental Enteral Nutr 7/98;22:206
Fish Oil No Benefit: HIV infected randomized to 1.7g/d for 6 months. Pichard, Geneva, AIDS 1/98;12:53
Hypertension & Pre-eclampsia
Fish Oil Decreased HBP: Johns Hopkins meta-analysis 17 trials fish oils for 3 mo or less. 3 gr/day of fish oil (6-10 caps [sic]) or more led to impressive reductions in HB. Systolic aver decr 5.5 and diastolic 3.5 mm Hg. Most pronounced for pt with highest BP ad no effect for normal BP. 28% c/o fishy taste or belching. Lawrence Appel, Arch Int Med 6/28/93;153:1429-38.
EPA+DHA Decreased HBP in DB: Highly refined ethyl esters used rather than fish oil in DB of 16 mild hypertensive and 16 normals. Both systolic and diastolic BP decreased over 2 mo by –5 mmHg and –6 mmHg but no additional decr over 2 more months. Prisco, U Florence, Thrombo Res 8/98;91:105-12
No Effect Found: Very small DB PC study 21 hypertensive adults 8 week fish oil with 4.5 g/d n-3 or placebo found both groups had sizeable decr BP. Fish oil group decreased TG 40% and increased LDL 19%. Gray, Long Beach VA, Pharmacother 3/96;16:295
Fish Oil Decreased HBP: DB PC 78 hypertensives 4.5g/d n-3 found fish oil decreased systolic 3.8 mmHg and dias 2.0 mmHg. Toft, Tromso, Ann Intern Med 12/95;123:911
Fish Oil Additive to Low Sodium Diet for HBP: 114 pt DB fish oil, vs. sunflower oil, vs. sodium tablets found that fish oil with sodium augmented to normal consumption levels no benefit but at low sodium levels pts had lower BP while with sunflower they did not. Cobiac, Adlaide, J Hypertension 1/92;10:87-92
Evening+Fish Oil Some Benefit pre-eclapsia: 13% lower incidence of edema. Mg Oxide helped HBP. 3 cases of eclampsia, all in placebo group. Women Health ’92;19:117-31
Cod Liver Oil by Pregnant Mothers Makes Kids More Intelligent: Pregnant women were recruited in week 18 of pregnancy to take 10 mL of cod liver oil or corn oil until 3 months after delivery. 341 women in study with 262 taking until delivery with goal of continuing to three months post-partum. 90 kids tested at 4 years. All had been breastfed at least 3 months. IQ 106.4 vs. 102.3, favoring DHA and EPA cod liver oil group. Maternal supplementation with very-long-chain n-3 fatty acids during pregnancy and lactation augments children's IQ at 4 years of age. Helland IB, Smith L, Saarem K, Saugstad OD, Drevon CA. Pediatrics 2003 Jan;111(1):e39-44
Better Cyclosporine Absorption and Metab in Kidney Transplants: 42 pt DB PC 6g/d highly concentrated DHA/EPA vs placebo decr to 3 g after 1 mo. After one year, Markedly decr creatinine and triglycerides in treatment group. Busnach, Milan, J Nephrol 3/98;11:87
Fish Oil Helps Kidney Failure: DB PC fish vs olive vs safflower. Fish oil decreased pro-inflammatory PGE2, incr hematocrit, decr pruritis, improved fatty acid profile. Peck, Purdue, J Am Diet Assoc 10/97;97(10 Suppl 2):S150
Fish Oil Helps Pruritis: DB PC 25 dialysis pt 6g/d n-3 fr fish oil vs safflower vs olive for 8 weeks found decr pruritis in fish oil group, incr plasma DHA and EPA, trend toward decr AA and incr(sic) PGE2. Peck, Purdue, Am J Clin Nutr 8/96;64:210
Slows Berger’s Disease: IgA Nephropathy is the most common type of primary glomerular nephritis and no rx has ever slowed progression including corticosteroids and cyclosporine. Mayo Clinic DB 2 yr study showed fish oil slowed progression, contrary to earlier studies. Nephron ’97;75:251.
No Benefit Diabetic Nephropathy: 36 IDDM pt rx 4.6g/d n-3 fish oil vs placebo for 1 year with no benefit fish oil. Rossing, Denmark, Diabetes Care 11/96;19:1214
Fish Oil Helps Mice: The influence of food restriction (40% overall reduction in intake of all dietary components) combined with substitution of fish oil for corn oil was studied in a factorial design. Autoimmune-prone (NZB x NZW)F(1) (B/W) mice, which develop fatal autoimmune renal disease, were used. The food-restricted/fish oil diet maximally extended median life span to 645 d (vs. 494 d for the food-restricted corn oil diet). Similarly, fish oil prolonged life span in the ad libitum-fed mice to 345 d (vs. 242 for the ad libitum/corn oil diet). Increased life span was partially associated with decreased body weight, blunting renal proinflammatory cytokine (interferon-gamma, interleukins-10 and -12 and tumor necrosis factor-alpha) levels and lower nuclear factor-kappaB (NF-kappaB). Reductions in NF-kappaB were preceded by enhanced superoxide dismutase, catalase and glutathione peroxidase activities. These findings demonstrate the profound additive effects of food restriction and (n-3) fatty acids in prolonging life span in B/W mice. J Nutr 2001 Oct;131(10):2753-60
Small Differential Fish/Soy Benefit in Japan: 29,000 adults in a 7-year follow-up study in which 2,000 died found high soy intake modest beneficial effect on mortality and fish was only significant for females. However, even the low intake quartile consumed 410 mg omega-3 per day v. 800-1000 average and 1600 mg high with 0.87 HR males and 0.77 females p=0.38 for males. High soy 166 g/d v 40 g/d for low with HR 0.83 both sexes. Am J Epid ’02;156:824-31. Ed: Fish and soy consumption in Japan is so common that even low consumers are eating as much as high consumers in mos other countries.
Heavy Fish Consumption No Added Benefit in Japan: In a 19-year follow-up of 8879 adults, there were 1745 deaths. Those who ate fish more than twice daily compared with those of subjects who ate 1 to 2 times weekly were 1% less like to die, no a significant difference ( OR =0.99 for all-cause, 1.26 for stroke, 0.92 for cerebral hemorrhage, 1.09 for cerebral infarction, and 0.91 (for coronary heart disease mortality). Association between fish consumption and all-cause and cause-specific mortality in Japan: NIPPON DATA80, 1980-99. Nakamura Y, Ueshima H, et al. Kyoto Women's University, Japan. Am J Med. 2005 Mar;118(3):239-45.
Fish Oil Helps Lupus: In a 24-week DB PC study of 52 systemic lupus erythematosus (SLE) patients, one group received 3 g MaxEPA fish oil and 3 mg copper, another 3 g MaxEPA and placebo copper, another 3 mg copper and placebo fish oil, and the fourth group received both placebo capsules. There was a significant decline in the lupus activity SLAM-R score from 6.12 to 4.69 (p < 0.05) in those subjects taking fish oil compared to placebo. No significant effect on SLAM-R was observed in subjects taking copper. The clinical effect of dietary supplementation with omega-3 fish oils and/or copper in systemic lupus erythematosus. Duffy EM, Meenagh GK, McMillan SA, Strain JJ, Hannigan BM, Bell AL. University of Ulster, UK. J Rheumatol. 2004 Aug;31(8):1551-6
Fish Oil Helps: DB cross over of low fat, high fish oil diet 27 pt with active SLE. 20 g/d MaxEPA capsules or 20g olive oil placebo with standard low fat diet. 34 weeks completed by 17, 14 of whom were on MaxEPA achieved benefit. 13 on placebo had no benefit or were worse. AJ Walton, Annals Rheu Disease (England) 7/91;50:463-6.
Fish Oil Helps SLE Mice: Fish oil vs. corn oil for 10% of diet. Corn oil shortened life span to 267 days and fish oil increased life span to 402 days. At 6.5 mo found increased proliferation response to T cell mitogens including bacterial superantigense and decreased anti-ds DNA Ab titers in fish oil group. Splenocytes of fish oil group had favorable changes. G Fernades, J Immunology (US) 6/15/94;152:5979-87.
Kills 1000 American per Year: African-Americans die from Lupus at a rate of 137/10 million annually vs. European-Americans at 10/10 million. Women are 5-6 times more likely to die. 16,000 contract the disease each year. CDC. Atlanta AP 5/3/02
Fish Oil Helps Primary Disease: DB PC 33 pt 17 wk fish oil with 6.6g/d n-3 vs. olive oil improved tolerance to cold and delayed vasospasm in primary but not secondary Raynaud’s. DiGiacomo, Albany, Am J Med 2/89;86:158.
Helps GI Surgery Recovery: DB PC study 154 pts s/p major GI surgery with parenteral arginine, dietary nucleotides and n-3 vs. standard found decr post-op infection. Senkal, Germany, Crit Care Med 9/97;25:1489
Low DHA in Retinitis Pigmentosa: Lining around night vision rods >50% DHA. If no Omega-3=animals with impaired vision.
Lower DHA in RP: Humans with RP had less DHA in RBCs than controls. Simonelli, U Naples, Opthalmic Res 28:93
Lower ARMD with DHA, Fish, Higher with linolenic acid: Harvard f/u 12 yr of 70,000 over 50yos found four servings per week fish assoc with 35% decrease in age-related macular degeneration. Lowest quintile in fat RR 1.54, high linolenic acid RR 1.4, high DHA RR 0.7. Amer J Clin Nutr 2/01;209
Fish Lowers Risk of Age-Related Maculopathy, Cholesterol Increases Risk: People (N = 3654) aged 49 or older. ARM identified from retinal photographs. A higher frequency of fish consumption was associated with decreased odds of late ARM (odds ratio for frequency of consumption more than once per week compared with less than once per month, 0.5). Subjects with higher energy-adjusted intakes of cholesterol were significantly more likely to have late ARM, with an increased risk for late ARM for the highest compared with the lowest quintile of intake (odds ratio, 2.7). Arch Ophthalmol 2000 Mar;118(3):401-4
Thomas E. Radecki, M.D., J.D.