A healthy balance of dietary omega 6 and omega 3 fatty acids is a prerequisite for normal immune function, cognitive health, and cardiovascular health. Among other factors, sufficient dietary levels of EPA, DHA or other omega 3 fatty acids are also important in the regulation of normal blood lipoprotein and healthy cholesterol metabolism. Fish oil supplements can also lower elevated triglyceride levels, improving cardiovascular health and reducing the risk of heart disease.†

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
Fish oils might slow blood clotting. Taking fish oils along with medications that also slow clotting might increase the chances of bruising and bleeding.Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.
Infant development. There is some evidence that mothers who eat fish or take fish oil supplements during pregnancy may improve some aspects of their baby's mental development. Taking fish oil during breast-feeding does not have this effect. However, feeding infants formula fortified with fish oil appears to improve some aspect of the baby's vision by the age of 2 months.
Yamagishi, K., Iso, H., Date, C., Fukui, M., Wakai, K., Kikuchi, S., Inaba, Y., Tanabe, N., and Tamakoshi, A. Fish, omega-3 polyunsaturated fatty acids, and mortality from cardiovascular diseases in a nationwide community-based cohort of Japanese men and women the JACC (Japan Collaborative Cohort Study for Evaluation of Cancer Risk) Study. J.Am.Coll.Cardiol. 9-16-2008;52(12):988-996. View abstract.
Augood, C., Chakravarthy, U., Young, I., Vioque, J., de Jong, P. T., Bentham, G., Rahu, M., Seland, J., Soubrane, G., Tomazzoli, L., Topouzis, F., Vingerling, J. R., and Fletcher, A. E. Oily fish consumption, dietary docosahexaenoic acid and eicosapentaenoic acid intakes, and associations with neovascular age-related macular degeneration. Am J Clin Nutr 2008;88(2):398-406. View abstract.
Brussels sprouts are a cruciferous vegetable bursting with vitamin K, vitamin C, and a healthy dose of omega-3 fatty acids. With their strong flavor and smell, however, they’re not always loved (or even tolerated) by children or adults with ADHD. If someone in your house considers sprouts the enemy, try this recipe — honey, cranberries, and parmesan cheese give these Brussels sprouts a sweet and savory flavor that even picky eaters love.

At SelfHacked, it’s our goal to offer our readers all the tools possible to get optimally healthy. When I was struggling with chronic health issues I felt stuck because I didn’t have any tools to help me get better. I had to spend literally thousands of hours trying to read through studies on pubmed to figure out how the body worked and how to fix it.
The current American diet has changed over time to be high in SFA and low in omega-3 fatty acids (12). This change in eating habits is centered on fast food containing high amounts of saturated fat, which has small amounts of essential omega-3 PUFA compared with food prepared in the home (13). Seafood sources such as fish and fish-oil supplements are the primary contributors of the 2 biologically important dietary omega-3 fatty acids, EPA and DHA (14–16). This low intake of dietary EPA and DHA is thought to be associated with increased inflammatory processes as well as poor fetal development, general cardiovascular health, and risk of the development of Alzheimer's disease (AD).
Because of the preliminary state of knowledge on the effects of omega-3 PUFA treatment on anxiety, we decided to include as many studies as possible and not to set further limitations on specific characteristics, such as length of study, diagnosis, omega-3 PUFA dosage, omega-3 PUFA preparation (EPA to DHA ratio), rated anxiety coding scale, or type of control. Therefore, we chose to make the inclusion criteria as broad as possible to avoid missing any potentially eligible studies. The inclusion criteria included clinical trials in humans (randomized or nonrandomized), studies investigating the effects of omega-3 PUFA treatment on anxiety symptoms, and formal published articles in peer-reviewed journals. The clinical trials could be placebo controlled or non–placebo controlled. The target participants could include healthy volunteers, patients with psychiatric illness, and patients with physical illnesses other than psychiatric illnesses. The exclusion criteria included case reports or series, animal studies or review articles, and studies not investigating the effects of omega-3 PUFA treatment on anxiety symptoms. We did not set any language limitation to increase the number of eligible articles. Figure 1 shows the literature search and screening protocol.
According to the American Heart Association (AHA), clinical trials have shown that omega-3 is effective in reducing the incidence of cardiovascular diseases (CVD). Fish oil is a great source of omega-3 and therefore, reduces the risk of heart diseases and heart arrhythmias. It also lowers the level of bad cholesterol (LDL) and increases the level of good cholesterol (HDL). Fish oil prevents the accumulation of triglycerides and also reduces the level of excess triglycerides. Preliminary research has shown that fish oil can be used to prevent atherosclerosis in coronary patients. Thus, fish oil is effective in preventing strokes and regular usage of fish oil can help avoid sudden cardiac death. As per the American Heart Association, these preliminary findings still need to be confirmed by a further detailed research.
Excessive amounts of chemicals. Using excessive amounts of fish products such as shark, farm raised salmon or mackerel can be dangerous. These products may be exposed to excessive amounts of chemicals such as mercury which can build up in the body and cause negative effects. While it is healthy to consume fish, it is important to seek out quality sources to avoid exposure to these chemicals. Using a supplement to get high levels of omega-3s into your system is also recommended because these products are produced in such a way that they will not expose you to unsafe chemicals.
Your concerns are very valid. The quality of commercially available omega-3 preparations can vary greatly. In our clinical trials we use preparations made by reputable manufacturers with high standards. We also have the preparations analyzed by 2 independent labs to confirm omega-3 content, impurities, and degree of oxidation, prior to initiating the study. While omega-3 fatty acids–like most nutrients–are ideally obtained through dietary practice, because many people may not enjoy omega-3 containing foods, supplements may be a good option for these individuals. Anyone who is interested in using an omega-3 preparation for treating a psychiatric condition should do so preferably under the supervision of a psychiatrist.
Omega−3 fatty acids, also called ω−3 fatty acids or n−3 fatty acids,[1] are polyunsaturated fatty acids (PUFAs).[2][3] The fatty acids have two ends, the carboxylic acid (-COOH) end, which is considered the beginning of the chain, thus "alpha", and the methyl (-CH3) end, which is considered the "tail" of the chain, thus "omega". One way in which a fatty acid is named is determined by the location of the first double bond, counted from the tail, that is, the omega (ω-) or the n- end. Thus, in omega-3 fatty acids the first double bond is between the third and fourth carbon atoms from the tail end. However, the standard (IUPAC) chemical nomenclature system starts from the carboxyl end.
The studies recruited men and women, some healthy and others with existing illnesses from North America, Europe, Australia and Asia. Participants were randomly assigned to increase their omega 3 fats or to maintain their usual intake of fat for at least a year. Most studies investigated the impact of giving a long-chain omega 3 supplement in a capsule form and compared it to a dummy pill.  Only a few assessed whole fish intake. Most ALA trials added omega 3 fats to foods such as margarine and gave these enriched foods, or naturally ALA-rich foods such as walnuts, to people in the intervention groups, and usual (non-enriched) foods to other participants.
Weak bones (osteoporosis). Research suggests that taking fish oil alone or together with calcium and evening primrose oil slows the rate of bone loss and increases bone density at the thigh bone (femur) and spine in elderly people with osteoporosis. But taking fish oil does not slow bone loss in older people with osteoarthritis in the knee but without weak bones.