Fish oil benefits, fish oil side effects, fish oil dosage, fish oil supplements
updated on November 21, 2011
Fish Oil Reviews - Omega 3-fatty Acids
Meat-lover diets are overwhelmed by saturated animal fat and omega-6 fatty acids. Saturated fats from mammal
products contribute to many chronic inflammatory and autoimmune diseases. Omega-6 fatty acid (linoleic acid) is in most
vegetable and cooking oils and is the primary oil used in processed and fast foods. Some of this fat may break down into
arachidonic acid that may enhance inflammation.

Omega 3 fatty acids and gamma linoleic acid are good fats, but we always have too little in our diets. Gamma linoleic acid
can be found in
borage seed oil and evening primrose seed oil, while omega 3 fatty acids are found in cold-water fishes,
and some plants oils such as
flaxseed, olive and canola oils.

Omega 3 fatty acid is a group of fatty acids characterized by a double bond that sits three carbons down from the n
terminal of the molecule, e.g. eicosapentaenoic acid. [1] N-3 Omega
3 polyunsaturated fatty acids have well documented
anti-inflammatory effects in vitro and have also been demonstrated to have health benefits in a range of chronic
inflammatory diseases. [2] Fishes that give good fats include mackerel, tuna, salmon, sturgeon, mullet, bluefish,
anchovy, sardines, herring, trout, and menhaden. They provide about 1 gram of omega-3 fatty acids in about 3.5 ounces
of fish.In general, the colder the water they live in, the more omega-3 oil in the fish. Fish oils are commonly combined
with vitamin E, calcium, iron, or vitamins A, B1, B2, B3, C, or D.


Cardiaovascular events
Fish oil benefits are many. Fish oil is used for a wide range of conditions. Studies have suggested that fish oil benefits
people at risks of conditions related to the heart and blood system. Fish oil offers health benefits of blood pressure or
triglyceride levels lowering. Fish oil may help prevent heart disease or stroke. The scientific evidence suggests that fish
oil really does have health benefits to those with high triglycerides, and fish oil also seems to be able to prevent heart
disease and stroke when taken in the recommended amounts. However, overdoses of fish oil can increase the risk of

Cognitive and Neuronal Conditions
Fish has been considered as “brain food” for years, eating fish may benefit some people with depression, psychosis,
attention deficit-hyperactivity disorder, Alzheimer’s disease, and other cognitive disorders. Fish oil may also benefit some
people suffered from dry eyes, glaucoma, and age-related macular degeneration.

Pain and Other Conditions
Fish oil supplements may also help ladies to prevent painful periods; breast pain; and complications associated with
pregnancy such as miscarriage, high blood pressure late in pregnancy, and early delivery. Fish oil may offer health
supports or benefits for people suffered from diabetes, asthma, developmental coordination disorders, movement
disorders, dyslexia, obesity, kidney disease, osteoporosis, psoriasis, and side effects of some cancer drugs.

Omega-3 Polyunsaturated Fatty Acids - Benefits
The health benefits of eating fish seems to be different from intake of fish oil supplements. Eating fried fish or fish
sandwiches may not have the benefits of fish oil, they may actually increase heart disease risk. Further, fish may also
contain heavy metals or other contaminants. Further, fish oil contains high concentrations of two of the most important
omega-3 fatty acids contained in fish oil are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
Supplementation of the maternal diet in pregnancy with omega-3 polyunsaturated fatty acids may provide a non-invasive
intervention with significant potential to prevent the development of allergic and possibly other immune-mediated
diseases or even cancers. [2, C1]  Fish-oil-derived monounsaturated fatty acids improved glucose/lipid homeostasis and
hindered the development of metabolic syndrome in obese mice. [A2] Omega-3 polyunsaturated fatty acids (ω3 PUFA)
are major components of brain cells membranes. ω3 PUFA-deficient rodents exhibit severe cognitive impairments
(learning, memory). ω3 PUFA supplementation is able to lower anxiety and to improve several cognitive parameters in
rodents. The long-term dietary ω3 PUFA from fish oil supplementation positively benefits on anxiety and cognitive
performances in the adult mouse lemur. [29] Epidemiological, preclinical and clinical data have enlightened the possible
benefits of n-3 PUFA in Alzheimer's disease. [A3] For details, please, review:

Fish oil is LIKELY SAFE for most healthy people, at dosage: of 3 grams or less per day.

Fish oil can cause many side effects including belching, bad breath, heartburn, nausea, loose stools, rash, and
nosebleeds. Taking fish oil supplements with meals or freezing them can often decrease these side effects, but this
action may alter the effectiveness of the fish oil supplements.

High Dosage of fish oil supplements: Taking high doses of fish oil is NOT safe. Taking more than 3 grams per day can
increase the chance of bleeding. High doses of fish oil might also reduce the immune system’s activity, reducing the body
defense. High dosage of fish oil supplement may also increase levels of the “bad” LDL cholesterol in some people. You
will need blood tests from time to time to monitor the LDL levels.

Duration and Fish Oil Side Effects
Fish oil side effects vary depending on the brand, dosage and the user physical conditions. Low dose fish oil extracts are
found to be beneficial to healthy, older or sick subjects, but long-term use of high dose fish oil may lead to harmful side
effects. [8] The most common side effects of fish oil supplements include fishy odor on the breath, stomach upset,
gastrointestinal disturbances, and greasy stools. To avoid the unpleasant fish oil taste and gastrointestinal side effects,
researchers suggested using enteric-coating to prepare the fish-oil supplements. [9]

Fish Oil Side Effects and Users' Conditions
Fish oil side effects have been observed and reported in subjects with various health conditions. Insignificant side effects
were noted with patients suffered from sporadic adenomas [10], arthritis [11-12], asthma [13], depression [14], and
systemic lupus erythematosus [15,16]. No untoward or only mild gastrointestinal side effects were observed in patients
suffered from cancer. [17-20], from high blood pressure [21,22], from high triglyceride or cholesterol [23, 24] However,
potential side effects such as gastrointestinal distress, prolonged bleeding, and vitamin A toxicity may happen to patients
suffered from pruritus. [25]

In a study of healthy male subjects, supplementation of purified fish oil to eight healthy male subjects led to reduced
platelet aggregation and whole blood viscosity. [7] This may be a good news for people with high blood viscosity, but it
may lead to prolonged bleeding under certain conditions. [25]

Contaminants in Fish
As discussed in the previous sections, some fishes such as shark, king mackerel, and farm-raised salmon, may contain
mercury and other industrial and environmental chemicals, but fish oil supplements typically do not contain these
contaminants. It is because there is a purification process for the fish oil supplement preparations.

Intake of fish is a major source of exposure to mercury, and a high content of mercury probably inhibits the beneficial
effects of omega-3 fatty acids on the development of coronary artery disease. In some studies no beneficial effects of
fish intake on coronary heart disease could be found; one Finnish study even found a positive correlation between
intake of freshwater fish and coronary heart disease. Researchers explained this paradox due to a high content of
mercury in fish. In one study the odds ratio for myocardial infarction in those with the highest content of mercury was
2.16. They also observed a positive correlation between mercury in hair and the progression of carotid atherosclerosis.

Fish Oil Supplements and Dosage
The optimal dosage of omega 3 fatty acid is not yet determined. However, fish oil dosage of 1 g has shown to reduce
overall and cardiovascular mortality, myocardial infarction, and sudden cardiac death. Higher dosages may be used for
its potent triglyceride-lowering effects and for patients with rheumatoid arthritis to reduce non-steroidal anti-inflammatory
use. American Heart Association Dietary Guidelines committee to recommend to the general population the consumption
of the dosage -- at least two servings of fatty fish per week, in addition to vegetable oils high in alpha-linolenic acid. [27]
Omega-3 fatty acid supplementation of infant formula has shown benefits in infant neural growth and development. [3,4]
Most commercial products of fish oil are in dosage form of softgels. The maximum dosage is about 3 g, total of EPA/DHA
per day. Be sure to check the labels: the label may say “1 g of fish oil” but it may contain a petite amount of EPA and
DHA. Look for high potency products, so you don’t need to take so many softgels a day.

To minimize the fish oil side effects such as belching and flatulence, one should avoid taking the entire dosage at one
time. Try splitting a 3 g daily dosage into three 1 g dosages, and take throughout the day with meals. Fish side effects
depend on the brand that you use, if you have trouble tolerating one fish oil supplement, try switching to another brand.
Fish Oil Benefits   Fish oil  - Manufacturing  Fish Oil Side Effects - High Dosages (Expt)        

Send your comment on this article to:

[1] Jatoi A Fish oil, lean tissue, and cancer: is there a role for eicosapentaenoic acid in treating the cancer anorexia/weight loss syndrome?
Crit Rev Oncol Hematol. 2005 Jul;55(1):37-43. [2] Dunstan JA and Prescott SL Does fish oil supplementation in pregnancy reduce the risk of
allergic disease in infants? Curr Opin Allergy Clin Immunol. 2005 Jun;5(3):215-21. [3] Oh R Practical applications of fish oil (Omega-3 fatty
acids) in primary care. J Am Board Fam Pract. 2005 Jan-Feb;18(1):28-36. [4] Stephensen CB Fish oil and inflammatory disease: is asthma
the next target for n-3 fatty acid supplements? Nutr Rev. 2004 Dec;62(12):486-9. [5] Zeller FP and Spears C Fish oil: effectiveness as a
dietary supplement in the prevention of heart disease. Drug Intell Clin Pharm. 1987 Jul-Aug;21(7-8):584-9. [6] Herold PM and Kinsella JE
Fish oil consumption and decreased risk of cardiovascular disease: a comparison of findings from animal and human feeding trials. Am J
Clin Nutr. 1986 Apr;43(4):566-98. [7] Terano T Effect of oral administration of highly purified eicosapentaenoic acid on platelet function,
blood viscosity and red cell deformability in healthy human subjects. Atherosclerosis. 1983 Mar;46(3):321-31.] [8] Bartoli GM Dietary fish oil
inhibits human erythrocyte Mg,NaK-ATPase. Biochem Biophys Res Commun. 1995 Aug 24;213(3):881-7. [9] Belluzzi A Effect of an enteric-
coated fish-oil preparation on relapses in Crohn's disease. N Engl J Med. 1996 Jun 13;334(24):1557-60. [10] In a study, 60 patients with
sporadic adenomas received low dose fish oil for 30 days. Side effects were found to be insignificant. Anti M Effects of different doses of fish
oil on rectal cell proliferation in patients with sporadic colonic adenomas. Gastroenterology. 1994 Dec;107(6):1709-18. [11] No significant
fish oil side effects were detected in a 12 week-study of fish oil on 8 patients with arthritis. Astorga G Active rheumatoid arthritis: effect of
dietary supplementation with omega-3 oils. A controlled double-blind trial Rev Med Chil. 1991 Mar;119(3):267-72. [12] No serious side
effects were observed when 51 patients with arthritis supplemented with fish oil extracts for 12 weeks. Faarvang KL Fish oils and
rheumatoid arthritis. A randomized and double-blind study. Ugeskr Laeger. 1994 Jun 6;156(23):3495-8. [13] No significant fish oil side
effects were observed, after 29 children suffered from asthma were supplemented with fish oil for 10 months. Nagakura T. Dietary
supplementation with fish oil rich in omega-3 polyunsaturated fatty acids in children with bronchial asthma. Eur Respir J. 2000 Nov;16(5):
861-5. [14] Twelve patients with depressive symptoms were treated with 1.5 to 2 g/day of fish oil for 6 months. No patients developed
hypomania or manic symptoms. No significant fish oil side effects were reported. Osher Y Omega-3 eicosapentaenoic Acid in bipolar
depression: report of a small open-label study. J Clin Psychiatry. 2005 Jun;66(6):726-9. [15] No major side effects were noted in a study of
27 patients with active systemic lupus erythematosus supplemented with high fish oil. Walton AJ Dietary fish oil and the severity of
symptoms in patients with systemic lupus erythematosus. Ann Rheum Dis. 1991 Jul;50(7):463-6. [16] Oral supplementation of fish oil
extracts induced prolonged remission of SLE in 10 consecutive patients without any side-effects. Das UN Beneficial effect of
eicosapentaenoic and docosahexaenoic acids [fish oil extracts] in the management of systemic lupus erythematosus and its relationship to
the cytokine network. Prostaglandins Leukot Essent Fatty Acids. 1994 Sep;51(3):207-13. [17] Patients with malignancy and weight loss > or
= 2% of body weight in the preceding month took concentrated, high-doses of fish oil that were supplied by the NIH. A majority of patients did
not gain weight and There was marked variability in the tolerability of the capsules, and many patients had gastrointestinal side effects.
[Burns CP et al Phase II study of high-dose fish oil capsules for patients with cancer-related cachexia. Cancer. 2004 Jul 15;101(2):370-8.]
[18] Postsurgical cancer patients receiving fish oil/medium-chain triglyceride structured lipid experienced no untoward side effects. Kenler
AS Early enteral feeding in postsurgical cancer patients. Fish oil structured lipid-based polymeric formula versus a standard polymeric
formula. Ann Surg. 1996 Mar;223(3):316-33. [19] EPA (95% pure, fish oil) was administered to 26 patients suffered from pancreatic cancer
for a few weeks. Fish oil supplementation was well tolerated, with only five patients experiencing side effects possibly attributable to the
EPA. Wigmore SJ Effect of oral eicosapentaenoic acid on weight loss in patients with pancreatic cancer. Nutr Cancer. 2000;36(2):177-84.
[20] Patients undergoing major abdominal surgery for upper gastrointestinal malignancies receiving fish oil/medium-chain triglyceride
structured lipid experienced no untoward side effects demonstrated a general trend toward improved hepatic, renal and immune function
found in the previous study. Swails Effect of a fish oil structured lipid-based diet on prostaglandin release from mononuclear cells in cancer
patients after surgery. JPEN J Parenter Enteral Nutr. 1997 Sep-Oct;21(5):266-74. [21] Common fish oil side effects are eructation and a fishy
taste, in six studies of 291 untreated hypertensives. Appel LJ. Does supplementation of diet with 'fish oil' reduce blood pressure? A meta-
analysis of controlled clinical trials. Am J Kidney Dis. 1993 Jul;22(1):151-7. [22] Fish oil may help prevent coronary artery disease. Four
studies of total 203 subjects were reviewed.  Fish oil was found to be able reduce diastolic blood pressure and triglyceride level.
Gastrointestinal side effects were observed in one study.  [Sommerfield T et al, Omega-3 fatty acids for intermittent claudication. Cochrane
Database Syst Rev. 2004.] [23] In an open study of 3,958 hyperlipemic patients, 471 subjects supplemented with fish oil experienced
gastrointestinal side effects. Kunzel U[Clinical experiences with a standardized fish oil concentrate. Field study with 3,958 hyperlipemic
patients in the practice of an established physician] Fortschr Med. 1990 Jul 30;108(22):437-42. [24] Minor gastrointestinal side effects were
reported in a study of fish oil using 48 patients with hypertriglyceridaemia. Miller JP Triglyceride lowering effect of MaxEPA fish lipid
concentrate (oil): a multicentre placebo controlled double blind study. Clin Chim Acta. 1988 Dec 30;178(3):251-9. [25] Vergili-Nelsen JM
Benefits of fish oil supplementation for hemodialysis patients. J Am Diet Assoc. 2003 Sep;103(9):1174-7. [26] Terano T Changes in fatty
acid composition, platelet aggregability and RBC function in elderly subjects with administration of low-dose fish oil concentrate and
comparison with younger subjects Nippon Ronen Igakkai Zasshi. 1994 Aug;31(8):596-603. [27] Eilat-Adar S et al, Omega-3 fatty acids, fish,
fish oil and cardiovascular disease--a review with implications to Israeli nutritional guidelines Harefuah. 2004 Aug;143(8):585-91, 622, 621.
[28] Landmark K and Aursnes I Mercury, fish, fish oil and the risk of cardiovascular disease Tidsskr Nor Laegeforen. 2004 Jan 22;124(2):
198-200 [29] Vinot N, et al, PLoS One. 2011;6(6):e20491. [A1] European Journal of Cancer Prevention 13(2): 159-164, June 2004] [A2] Yang
ZH et al, J Agric Food Chem. 2011 Jun 10.] [A3] Calon F, Curr Alzheimer Res. 2011 May 23] [A4] Solfrizzi V et al, Expert Rev Neurother. 2011
May;11(5):677-708.] [B1] DeFina LF, Marcoux LG, Devers SM, Cleaver JP, Willis BL. Effects of omega-3 supplementation in combination with
diet and exercise on weight loss and body composition. Am J Clin Nutr. 2011 Feb;93(2):455-62 [B2] Weed HG, Ferguson ML, Gaff RL,
Hustead DS, Nelson JL, Voss AC. Lean body mass gain in patients with head and neck squamous cell cancer treated perioperatively with a
protein- and energy-dense nutritional supplement containing eicosapentaenoic acid. Head Neck. 2011 Jul;33(7):1027-33. [B3] Cho JY, Chi
SG, Chun HS. Oral administration of docosahexaenoic acid attenuates colitis induced by dextran sulfate sodium in mice. Mol Nutr Food
Res. 2011 Feb;55(2):239-46. [B4] Rubin MG, Kim K, Logan AC.Acne vulgaris, mental health and omega-3 fatty acids: a report of cases.
Lipids Health Dis. 2008 Oct 13;7:36. [B5] Brinson BE, Miller S. Fish Oil: What is the Role in Cardiovascular Health? J Pharm Pract. 2011 Jun
6 [B6] Yamazaki RK, Brito GA, Coelho I, Pequitto DC, Yamaguchi AA, Borghetti G, Schiessel DL, Kryczyk M, Machado J, Rocha RE, Aikawa J,
Iagher F, Naliwaiko K, Tanhoffer RA, Nunes EA, Fernandes LC. Low fish oil intake improves insulin sensitivity, lipid profile and muscle
metabolism on insulin resistant MSG-obese rats.Lipids Health Dis. 2011 Apr 28;10:66. [C1] aA study of mice found. Mom's Diet May Reduce
Breast Cancer Risk in Daughters, Health Day, April 20, 2005.
Discuss with your doctor before taking any alternative medicine. This article is for
reference only, it is not a medical advice. All rights reserved. Do not copy this article to
other website or blog.