HEALTH BENEFITS. Omega-3 Fish Oil

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1 HEALTH BENEFITS Omega-3 Fish Oil

2 Omega-3 fatty acids are essential polyunsaturated fats. They cannot be manufactured by the body and therefore must be consumed through food or supplements. Three types of omega-3s include ALA (alphalinolenic acid), EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). ALA is found in plant foods such as flaxseeds and nuts, while EPA and DHA are found in fatty fish such as salmon, herring, sardines, tuna, trout, and mackerel. Wild-caught fatty fish generally contain a higher percentage of omega-3 fats than farm-raised fish. Because EPA and DHA are found in fish, they are often referred to as marine-derived omega-3 fatty acids, or simply fish oils. Which Omega-3s are most beneficial? A diet rich in omega-3 fats has been shown to be heart-healthy. While there is substantial evidence that EPA and DHA reduce the risk of heart disease, the effect of ALA on the risk of heart health is less established. Due to the strength of the evidence for fish oil, the FDA (U.S. Food and Drug Administration) has approved the following health claim: Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease. Omega-3 fish oils are among a small list of foods or nutrients that the FDA allows to carry this type of health claim. Comparing Fish Oil Supplements For those who do not eat enough fish, a fish oil supplement can be beneficial. However, these products vary a lot in their amount of EPA and DHA, as well as in quality and safety, and thus it is important to consider a few things before purchasing a fish oil supplement. Choose a supplement that has been independently tested and certified for content accuracy, purity, and freedom from contaminants. The International Fish Oil Standards (IFOS) program tests products for PCBs, mercury, and other contaminants that can be found in fish, and they compare the EPA/DHA concentration in the product with its label claim. Be sure the supplement has been molecularly distilled to remove contaminants and decrease the likelihood of fishy smell and aftertaste. Determine the amount of EPA and DHA in the supplement, and then compare the cost based on the total amount of EPA and DHA. Should I take fish oil supplements if I eat fish? Healthy individuals who eat fatty fish more than twice a week may not need a daily supplement. If you do not eat fish often, or if you have heart disease or another condition that may benefit from higher doses of EPA and DHA, you should consider taking a fish oil supplement. If you have a question about your diet and the need for supplementation, consult your healthcare provider. Omega-3 Fish Oils and Heart Disease Scientific research has shown that omega-3 fish oils decrease the risk of heart disease, as well as the number of deaths from heart disease and all other causes. 1,2,3 Omega-3s have also been shown to decrease triglyceride levels, decrease the risk of blood clots and ischemic stroke, slightly lower blood pressure, decrease inflammation, and enhance the effectiveness of cholesterol-lowering

3 Consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease. - FDA. (statin) medications In the GISSI-Prevention Study, a large randomized trial of 11,324 patients with pre-existing heart disease, a daily EPA and DHA supplement reduced the incidence of nonfatal heart attack and stroke by 15%, allcause mortality (death from all causes) by 20%, and sudden cardiac death by 45%. 12 A significant reduction in mortality was found after only three months of supplementation, and a decrease in sudden death was seen after only four months of supplementation. 13 Cardiovascular diseases are the leading cause of death for men and women with diabetes. Eating fatty fish or taking a fish oil supplement is important, especially for people with diabetes who may also have elevated triglyceride levels. The American Diabetes Association recommends that individuals with diabetes increase omega-3 intake by eating two to three servings of fatty fish per week. Omega-3 Fish Oils and Prostate Cancer The Health Professionals Follow-up Study, which followed about 50,000 men for ten years, showed that men who ate fish more than three times per week had a lower risk of prostate cancer, especially advanced prostate cancer, and a lower risk of death from the disease than men who ate fish only twice a month or less. 14 In addition, men who ate more fish after being diagnosed with prostate cancer had a reduced risk of prostate cancer recurrence. 15 These benefits are thought to be due to EPA and DHA, the omega-3s that have been shown to slow the growth and spread of prostate cancer cells in the lab. 16 Men considered at risk of prostate cancer, or those who have had prostate cancer, should consider increasing their intake of fatty fish to two to three times per week or taking a high-quality fish oil supplement providing at least 500 mg EPA and DHA per day. Omega-3 Fish Oils and Arthritis EPA and DHA are thought to be beneficial for painful joints because of their anti-inflammatory properties. In people with rheumatoid arthritis, fish oil supplements have been shown to decrease joint pain, morning stiffness, the number of tender joints, and reduce the use of nonsteroidal antiinflammatory drugs (NSAIDs) No clinical trials have tested omega-3 fish oils in patients with osteoarthritis, though animal studies and models have suggested that omega-3 fats may provide 20, 21 some benefit. Omega-3 Fish Oils and Macular Degeneration Omega-3 fish oils are thought to promote eye health. DHA is found in high concentrations in the cell membranes of the retina. One study found that among people at an increased risk of age-related macular degeneration (AMD), those who had the highest intakes of EPA and DHA were about 30% less likely to develop AMD compared to those with low intakes. 22 Omega-3 Fish Oils and Mental Health Omega-3 fish oils appear to play an important role in brain function. DHA is the major fat found in the brain. Higher intakes of DHA and EPA have been associated with a decrease in symptoms of depression in women. 23 Fish consumption has

4 Because of the convincing evidence for omega-3 fish oils, the American Heart Association recommends all adults eat a variety of fish at least twice weekly. been linked to a decreased risk of Alzheimer s and other types of dementia and may decrease the rate of cognitive decline during normal aging and in those with mild Alzheimer s disease It is not known whether taking a fish oil supplement can help decrease the risk or progression of Alzheimer s disease. Omega-3 Fish Oils and Pregnancy There have been many studies looking into the effects of fish and omega-3 fats on fetal development and pregnancy outcome. Fish intake during pregnancy has been associated with healthier birth weight, reduced preterm delivery, and reduced asthma and allergy in babies Maternal stores of DHA decrease during pregnancy and lactation as the DHA is transferred to the fetus and newborn. Pregnant and lactating women in the U.S. average less than 25% of the recommended intake for DHA. 32 Women who are pregnant, may become pregnant, or who are breastfeeding, as well as children under 12 years of age, can safely consume up to 12 ounces of a variety of fish and shellfish per week. 33 Common fish with low levels of mercury include shrimp, canned light tuna, salmon, pollock, and catfish. Pregnant women and children should not eat certain fish highest in mercury (shark, swordfish, king mackerel, and tilefish) and limit white (albacore) tuna to six ounces or less per week. Pregnant women and breastfeeding mothers are advised to aim for an intake of at least 200 mg DHA per day. 34 Fish and Omega-3 Recommendations for the General Population Because of the convincing evidence for omega-3 fish oils and heart health, the American Heart Association (AHA) recommends that all adults eat a variety of fish, particularly fatty fish, at least twice weekly. If these meals include salmon, for example, two six-ounce servings per week provide an average of about 600 mg EPA and DHA per day. The AHA recommends that adults who have heart disease consume a total of approximately 1 gram per day of EPA and DHA from fatty fish or fish oil supplements, and adults trying to lower triglyceride levels consume 2 4 grams per day of EPA and DHA from fish oil capsules. 35 The AHA recommends that patients follow these guidelines under their physicians care. Safety of Omega-3 Fish Oil The FDA has ruled that intakes of up to 3 grams (3,000 mg) per day of EPA and DHA are generally safe. 36 The most common side effect of lowquality fish oil supplements is a fishy aftertaste. However, higher-quality fish oil supplements that have been molecularly distilled should present less of a problem. If you experience these side effects, try keeping your fish oil supplement in the freezer. Stomach upset, which is not generally seen with intakes up to 1 gram per day, may occur at higher intake levels. Taking fish oil supplements with food will help minimize this risk. With doses greater than 3 grams per day, there is a possible increased risk of clinical bleeding and increases in LDL cholesterol. Individuals taking blood thinners should exercise caution in the use of fish u

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