Protects Vision: Our eyes' retinas are a membranous structures and the whole eye is covered in a soft double layer of membranes, making your eyes' health dependent on the liver (who knew?). The liver helps metabolize fat-soluble vitamins that feed and maintain those membranes. If you're deficient in DHA, it affects how we see by delaying the system that converts light into neural energy in the retina.
The competition between EPA and DHA during digestion and absorption and the fact that DHA appears to ‘block’ the therapeutic actions of EPA can therefore be an issue if we are looking to optimise the benefits associated with EPA (Martins 2009; Bloch & Qawasmi et al, 2011; Sublette et al, 2011). High dose, high concentration and high ratio EPA supplements increase the effectiveness in depression studies, and pure EPA-only is optimal. Depression is also a condition with an inflammatory basis, so this is likely another significant reason for EPA being the key player – its antagonistic relationship with the inflammatory omega-3 AA (arachidonic acid) is very effective at reducing inflammation.
Thank you for your kind comment. As pointed out above, the main limitation of our meta-analysis is the heterogeneity, which we address several times in our main manuscript. We included studies with several different situations and participants with different underlying diseases, which would also result in wide heterogeneity in our meta-analysis. Based upon our post-hoc analysis, there was some common characteristics among the six trials with nominally significant results, including specific clinical diagnoses (5/6) and, placebo-control (4/6), which had also previously been addressed in our subgroup meta-analysis. Therefore, we suggested future placebo-controlled trials investigating the treatment effect of omega-3 in participants with specific clinical diagnoses should be warranted. In addition, improving underlying specific clinical diagnoses (5/6), good quality (placebo-control (4/6), low drop-out rate (zero in Exp/control groups: 4/6)), and long treatment duration (>= 12 weeks: 4/6) are all good indicators of high quality.
42. Cawood AL, Ding R, Napper FL, Young RH, Williams JA, Ward MJ, Gudmundsen O, Vige R, Payne SP, Ye S, et al. Eicosapentaenoic acid (EPA) from highly concentrated n-3 fatty acid ethyl esters is incorporated into advanced atherosclerotic plaques and higher plaque EPA is associated with decreased plaque inflammation and increased stability. Atherosclerosis. 2010;212:252–9. [PubMed]
As a result, we depend on our diet to get the necessary Omega-3 fatty acids into our bodies. These two fatty acids work together in human health. DHA helps with cell membrane structure and assists in normal growth and development. While both EPA and DHA participate in key pathways of the immune system where they control key processes that support our health. Together they provide a number of important health benefits throughout our lifetime.

My optometrist explained to me how important a good quality fish oil was to my eye health because I have dry eye due to inflammation. Little did I realize that it would be go for so many other things. Since I have been taking this product, not only have I had improvement with my dry eyes, but I have less joint pain from my osteoarthritis! I am so happy I found this and plan to continue it as part of my regular supplement routine! Thanks BioScience Nutrition!
The supplements contain omega-3 fatty acids, the polyunsaturated oils prominent in fatty cold water fish like salmon, sardines and mackerel. In many observational studies, people who regularly consumed fish two or more times a week were less likely to suffer heart attacks, strokes and cardiovascular deaths than those who ate fish infrequently or not at all.
Gajos G1, Rostoff P, Undas A, et al. Effects of polyunsaturated omega-3 fatty acids on responsiveness to dual antiplatelet therapy in patients undergoing percutaneous coronary intervention: the OMEGA-PCI (OMEGA-3 fatty acids after pci to modify responsiveness to dual antiplatelet therapy) study. J Am Coll Cardiol. 2010 Apr 20;55(16):1671-8. View abstract.
As a result, we depend on our diet to get the necessary Omega-3 fatty acids into our bodies. These two fatty acids work together in human health. DHA helps with cell membrane structure and assists in normal growth and development. While both EPA and DHA participate in key pathways of the immune system where they control key processes that support our health. Together they provide a number of important health benefits throughout our lifetime.
In a U.K. study, children of mothers who ate more than 12 ounces a week actually scored better on tests of verbal I.Q., social behavior, and development and communication than children of mothers who ate none. In the Seychelles Islands, where people average 12 fish meals -- not ounces -- a week, there are no reports of links between mercury exposure and poor outcomes in children. These studies suggest that eating less than 12 ounces of fish each week could do more harm to a child's developing neurological system than mercury poisoning.
Guallar, E., Aro, A., Jimenez, F. J., Martin-Moreno, J. M., Salminen, I., van't Veer, P., Kardinaal, A. F., Gomez-Aracena, J., Martin, B. C., Kohlmeier, L., Kark, J. D., Mazaev, V. P., Ringstad, J., Guillen, J., Riemersma, R. A., Huttunen, J. K., Thamm, M., and Kok, F. J. Omega-3 fatty acids in adipose tissue and risk of myocardial infarction: the EURAMIC study. Arterioscler.Thromb.Vasc.Biol 1999;19(4):1111-1118. View abstract.
Finally, in order for AA to be converted into inflammatory products it must be released from phospholipids (part of the cell membrane) using the enzyme phospholipase A2 and then converted by the enzyme cyclooxygenase. EPA utilises both of these enzymes, so if EPA levels are increased in the diet, it attracts enzyme away from AA to EPA – again giving rise to anti-inflammatory products instead of inflammatory ones.
Fish oil has the ability to treat Attention Deficit Hyperactivity Disorder (ADHD) due to its high concentration of fatty acids. For children suffering from hyperactivity, dyslexia, dyspraxia, inability to complete tasks, emotional instability, wavering attitude, poor coordination, short attention span, short-term memory weakness, low concentration, tendency to interrupt others, recklessness, hastiness, impetuosity, impulsiveness, low IQ, or learning disorders, fish oil is a proven remedy. Research conducted at the University of South Australia and CSIRO has shown that when children suffering from ADHD were given doses of fish oil and evening primrose capsules for 15 weeks, they showed significant improvements in their behavior. Since, human brain consists of about 60% fats, especially essential fatty acids such as omega-3 and omega-6, it helps to improve the functions of the brain.
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.
Brain function and vision rely on dietary intake of DHA to support a broad range of cell membrane properties, particularly in grey matter, which is rich in membranes.[61][62] A major structural component of the mammalian brain, DHA is the most abundant omega−3 fatty acid in the brain.[63] It is under study as a candidate essential nutrient with roles in neurodevelopment, cognition, and neurodegenerative disorders.[61]
Another study conducted by researchers at Rhode Island Hospital examined the relationship between fish oil supplementation and indicators of cognitive decline. The subjects of the study were older adults: 229 cognitively normal individuals, 397 patients with mild cognitive impairment and 193 patients with Alzheimer’s disease. They were assessed with neuropsychological tests and brain magnetic resonance imaging every six months while taking fish oil supplements. The study found that the adults taking fish oil (who had not yet developed Alzheimer’s and did not have genetic risk factor for developing Alzheimer’s known as APOE ε4) experienced significantly less cognitive decline and brain shrinkage than adults not taking fish oil. (9)
Samsonov, M. A., Vasil'ev, A. V., Pogozheva, A. V., Pokrovskaia, G. R., Mal'tsev, G. I., Biiasheva, I. R., and Orlova, L. A. [The effect of a soy protein isolate and sources of polyunsaturated omega-3 fatty acids in an anti-atherosclerotic diet on the lipid spectrum of blood serum and immunological indicators in patients with ischemic heart disease and hypertension]. Vopr.Med Khim. 1992;38(5):47-50. View abstract.
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.
Fearon, K. C., Von Meyenfeldt, M. F., Moses, A. G., Van Geenen, R., Roy, A., Gouma, D. J., Giacosa, A., Van Gossum, A., Bauer, J., Barber, M. D., Aaronson, N. K., Voss, A. C., and Tisdale, M. J. Effect of a protein and energy dense n-3 fatty acid enriched oral supplement on loss of weight and lean tissue in cancer cachexia: a randomised double blind trial. Gut 2003;52(10):1479-1486. View abstract.

Hooper, L., Thompson, R. L., Harrison, R. A., Summerbell, C. D., Ness, A. R., Moore, H. J., Worthington, H. V., Durrington, P. N., Higgins, J. P., Capps, N. E., Riemersma, R. A., Ebrahim, S. B., and Davey, Smith G. Risks and benefits of omega 3 fats for mortality, cardiovascular disease, and cancer: systematic review. BMJ 4-1-2006;332(7544):752-760. View abstract.

Good for you for eating healthily! Sadly, many people do not like omega-3 containing foods such as fish, and for these people, supplementation may be a good alternative to obtain omega-3. As a clinical investigator, my research focuses on study supplements, which is what I was asked to cover in this article. I’m all for healthy eating, but not everyone can afford it or wants to eat certain foods, and this is perhaps why supplements are so popular.
It is also believed that women who do not have a sufficient intake of EPA and DHA in their diet suffer from depression after childbirth, as there is a transfer of some amount of brain mass from the mother to the child in the last stages of pregnancy. Thus, it is very beneficial to consume fish oil either by eating fish or taking fish oil supplements, tablets, capsules, or pills during pregnancy for the overall development of the child and the well-being of the mother. However, it should be noted that fish oil obtained from the liver of the fish, example – cod liver oil, should not be consumed during pregnancy as cod liver oil is high in retinol and vitamin A, which are usually known to cause birth defects.
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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