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What are the benefits of cod liver oil? This article provides detailed information on the health benefits associated with cod liver oil, and its potential therapeutic properties. This article looks at some of the claims that cod liver oil might improve cardiovascular health, ease joint stiffness caused by arthritis, and repair wounds. Read on to learn more. Read now
Henneicke-von Zepelin, H. H., Mrowietz, U., Farber, L., Bruck-Borchers, K., Schober, C., Huber, J., Lutz, G., Kohnen, R., Christophers, E., and Welzel, D. Highly purified omega-3-polyunsaturated fatty acids for topical treatment of psoriasis. Results of a double-blind, placebo-controlled multicentre study. Br J Dermatol 1993;129(6):713-717. View abstract.
Results  In total, 1203 participants with omega-3 PUFA treatment (mean age, 43.7 years; mean female proportion, 55.0%; mean omega-3 PUFA dosage, 1605.7 mg/d) and 1037 participants without omega-3 PUFA treatment (mean age, 40.6 years; mean female proportion, 55.0%) showed an association between clinical anxiety symptoms among participants with omega-3 PUFA treatment compared with control arms (Hedges g, 0.374; 95% CI, 0.081-0.666; P = .01). Subgroup analysis showed that the association of treatment with reduced anxiety symptoms was significantly greater in subgroups with specific clinical diagnoses than in subgroups without clinical conditions. The anxiolytic effect of omega-3 PUFAs was significantly better than that of controls only in subgroups with a higher dosage (at least 2000 mg/d) and not in subgroups with a lower dosage (<2000 mg/d).
In many cases, people are recommended to consume fish oil because it is an easy way to get additional omega-3 fatty acids into their diet. Omega-3 fats can be used to reduce swelling or to prevent blood clots which could cause major cardiovascular damage. There are many other conditions which can be decreased or improved with the use of fish oil. In most cases fish oil is used to help reduce high triglycerides which can cause serious conditions like diabetes or heart disease.
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]
Two psychiatrists (P.-T.T. and T.-Y.C.) separately performed a systematic literature search of the PubMed, Embase, ProQuest, ScienceDirect, Cochrane Library, ClinicalKey, Web of Science, and ClinicalTrials.gov databases to March 4, 2018. Because we presumed some clinical trials would use investigating scales for some other mood symptoms but also contain symptoms of anxiety, we tried to use some nonspecific medical subject heading terms to include those clinical trials. Therefore, we used the following keywords: omega-3, eicosapentaenoic acid, EPA, DHA, or docosahexaenoic acid; and anxiety, anxiety disorder, generalized anxiety disorder, agoraphobia, panic disorder, or posttraumatic stress disorder. After removing duplicate studies, the same 2 authors screened the search results according to the title and abstract to evaluate eligibility. List of potentially relevant studies were generated for a full-text review. Any inconsistencies were discussed with a third author to achieve final consensus. To expand the list of potentially eligible articles, we performed a manual search of the reference lists of review articles in this area.12,38,39
Egert, S., Somoza, V., Kannenberg, F., Fobker, M., Krome, K., Erbersdobler, H. F., and Wahrburg, U. Influence of three rapeseed oil-rich diets, fortified with alpha-linolenic acid, eicosapentaenoic acid or docosahexaenoic acid on the composition and oxidizability of low-density lipoproteins: results of a controlled study in healthy volunteers. Eur J Clin Nutr 2007;61(3):314-325. View abstract.
Here is a brief on omega-3 fatty acids: There are three types of omega-3 fatty acids, namely alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA). All three are important for the body. Vegetable sources, including flaxseed oil, soybean oil, hemp oil, canola oil, walnut oil, rapeseed, perilla, chia, and tofu are rich in ALA. The human body has the ability to convert ALA to DHA and EPA, though there are certain limitations to this conversion.
Jump up ^ Miller M, Stone NJ, Ballantyne C, Bittner V, Criqui MH, Ginsberg HN, Goldberg AC, Howard WJ, Jacobson MS, Kris-Etherton PM, Lennie TA, Levi M, Mazzone T, Pennathur S (May 2011). "Triglycerides and cardiovascular disease: a scientific statement from the American Heart Association". Circulation. 123 (20): 2292–333. doi:10.1161/CIR.0b013e3182160726. PMID 21502576.
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Omega 3 fatty acids are monounsaturated fats that come from food sources—primarily cold water fish (eg, salmon, trout, tuna, mackerel, and herring)—that contain EPA (eicosapentaenoic acid) and docosahexaenoic acid (DHA). Other fatty acids are derived from plant-derived sources of food—including nuts (especially walnuts) and seeds (eg, flax, chia, sunflower)—that have primarily ALA (alpha-linolenic acid).
We’ve already seen that fish oil can help with depression-like symptoms in rats, but what about people? A study published in the journal Nutritional Neuroscience evaluated the effects of fish oil supplementation on prefrontal metabolite concentrations in adolescents with major depressive disorder. Researchers found that there was a 40 percent decrease in major depression disorder symptoms in addition to marked improvements in amino acid and nutrition content in the brain, specifically, the right dorsolateral prefrontal cortex. (21)
I've done a lot of shopping and comparing of fish oil softgels and have reached the conclusion that these are these best you can buy. Prior to seeing these in my chiropractor's office I scanned the labels and specs on many brands at Mothers, Vitamin Shoppe, Sprouts and Amazon vendors. These have 430 mg of EPA and 290 mg of DHA per softgel, with a recommended dose of two.. If you compare as well, you will find most other brands, including those sold as premium products at health food stores at premium prices don't have the same potency.Especially among Krill Oil products. My chiropractor shared a clinical study that showed taking fish oil containing levels of EPA and DHA consistent with these supplements caused participants to say it had the same favorable affect as taking ibuprofen. I make no claims. I am not a doctor, am not associated ... full review
Marine and freshwater fish oil vary in contents of arachidonic acid, EPA and DHA.[15] The various species range from lean to fatty and their oil content in the tissues has been shown to vary from 0.7% to 15.5%.[16] They also differ in their effects on organ lipids.[15] Studies have revealed that there is no relation between total fish intake or estimated omega−3 fatty acid intake from all fish, and serum omega−3 fatty acid concentrations.[17] Only fatty fish intake, particularly salmonid, and estimated EPA + DHA intake from fatty fish has been observed to be significantly associated with increase in serum EPA + DHA.[17]

People who eat seafood rich in EPA and DHA at least once a week are less likely to die of heart disease, according to the National Center for Complementary and Alternative Medicine. The fatty acids may also be helpful in relieving symptoms of rheumatoid arthritis. Fish oil has been rated as "Effective" by MedlinePlus for lowering high triglycerides, which can be a major risk factor for heart disease. Fish oil has been rated as "Likely Effective" for keeping healthy hearts free of disease. Although eating baked or broiled fish can reduce the risk of heart disease, fried fish or fish sandwiches not only cancel out any heart-healthy benefits, but may also contribute to heart disease, MedlinePlus notes.
Fish and omega-3 fatty acids. If you keep up with the latest nutrition news, you may have a pretty good sense of what they offer. But, if you're like many people, you still can't tell your omega-3s from your omega-6s -- and you sure as heck can't pronounce eicosapentaenoic acid. That's OK. Our fishing expedition turned up some interesting facts to share about omega-3 fatty acids and fish.

The strongest evidence for a beneficial effect of omega-3 fats has to do with heart disease. These fats appear to help the heart beat at a steady clip and not veer into a dangerous or potentially fatal erratic rhythm. (1) Such arrhythmias cause most of the 500,000-plus cardiac deaths that occur each year in the United States. Omega-3 fats also lower blood pressure and heart rate, improve blood vessel function, and, at higher doses, lower triglycerides and may ease inflammation, which plays a role in the development of atherosclerosis. (1)


Cardiovascular disease is the cause of 38% of all deaths in the United States, many of which are preventable (28). Chronic inflammation is thought to be the cause of many chronic diseases, including cardiovascular disease (29). EPA and DHA are thought to have antiinflammatory effects and a role in oxidative stress (30) and to improve cellular function through changes in gene expression (31). In a study that used human blood samples, EPA+DHA intake changed the expression of 1040 genes and resulted in a decreased expression of genes involved in inflammatory and atherogenesis-related pathways, such as nuclear transcription factor κB signaling, eicosanoid synthesis, scavenger receptor activity, adipogenesis, and hypoxia signaling (31). Circulating markers of inflammation, such as C-reactive protein (CRP), TNF α, and some ILs (IL-6, IL-1), correlate with an increased probability of experiencing a cardiovascular event (32). Inflammatory markers such as IL-6 trigger CRP to be synthesized by the liver, and elevated levels of CRP are associated with an increased risk of the development of cardiovascular disease (33). A study of 89 patients showed that those treated with EPA+DHA had a significant reduction in high-sensitivity CRP (66.7%, P < 0.01) (33). The same study also showed a significant reduction in heat shock protein 27 antibody titers (57.69%, P < 0.05), which have been shown to be overexpressed in heart muscle cells after a return of blood flow after a period of ischemia (ischemia-reperfusion injury) and may potentially have a cardioprotective effect (33).
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.
Birch, E. E., Carlson, S. E., Hoffman, D. R., Fitzgerald-Gustafson, K. M., Fu, V. L., Drover, J. R., Castaneda, Y. S., Minns, L., Wheaton, D. K., Mundy, D., Marunycz, J., and Diersen-Schade, D. A. The DIAMOND (DHA Intake And Measurement Of Neural Development) Study: a double-masked, randomized controlled clinical trial of the maturation of infant visual acuity as a function of the dietary level of docosahexaenoic acid. Am J Clin Nutr 2010;91(4):848-859. View abstract.
Several recent clinical studies, especially those focusing on the benefits of omega-3 in inflammatory conditions, have investigated the actions of pure-EPA in protecting against excess inflammation in the body. EPA works in several different ways. Firstly, it is the precursor to a number of immune messengers, collectively called ‘eicosanoids’ (series-3 prostaglandins, series-3 thromboxanes and series-5 leukotrienes,) all of which have anti-inflammatory roles.
There are numerous omega-3 sources with varying proportions of EPA and DHA, and the balance of EPA and DHA in a supplement influences the actions of these fats in the body. For more information about the different types of omega-3 sources and which are most suited for your individual needs, read our page on the different types of omega-3 supplements
Krill oil is a source of omega−3 fatty acids.[116] The effect of krill oil, at a lower dose of EPA + DHA (62.8%), was demonstrated to be similar to that of fish oil on blood lipid levels and markers of inflammation in healthy humans.[117] While not an endangered species, krill are a mainstay of the diets of many ocean-based species including whales, causing environmental and scientific concerns about their sustainability.[118][119][120]
You “beat me to the punch.” despite labels, cured meats , aged fats, as well as those heated to a high enough temperature all have trans bonds. Fish that offer high amounts of Omega-3 also often are high in mercury. I was fortunate to have a very good teacher for experimental design. One should be careful to assume that a study actually measures what it claims to and without “confounders” Confounders are parts of the study that complicate the the “logic” of the design. Also, were other fat contents measured or controlled? It would be reasonable to suspect that those with higher levels of Omega-3 could have higher levels of Omega-6, fats in general , High levels of protein, higher levels of testosterone, or lower levels of certain hormones. In addition, statistical studies do not and have never indicated a causal relationship. I have a fear of how much we have begun to rely on statistical correlational studies which are at the end of the day”soft” science.
Henneicke-von Zepelin, H. H., Mrowietz, U., Farber, L., Bruck-Borchers, K., Schober, C., Huber, J., Lutz, G., Kohnen, R., Christophers, E., and Welzel, D. Highly purified omega-3-polyunsaturated fatty acids for topical treatment of psoriasis. Results of a double-blind, placebo-controlled multicentre study. Br J Dermatol 1993;129(6):713-717. View abstract.
Weight loss. Some research shows that eating fish improves weight loss and decreases blood sugar in people who are overweight with high blood pressure. Early research also shows that taking a specific fish oil supplement (Hi-DHA, NuMega) lowers body fat when combined with exercise. But other evidence suggests that taking another specific fish oil supplement (Lovaza) does not lower body weight in overweight people.
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