Fish Oil Capsules in Heart Shaped Box
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It's no secret that your body needs omega-3 fatty acids to function properly. Omega-3 fatty acids are crucial for proper growth and development, normal brain function and overall heart health. They aren't manufactured inside your body, so the best way to get enough is through your diet. The American Heart Association advises having two servings of fatty fish, such as salmon, tuna or mackerel, each week. However, these fish can contain high levels of mercury, so taking a nutritional supplement high in omega-3 fatty acids is a viable alternative. Both krill oil and fish oil supplements contain omega-3 fatty acids, and they are available over the counter. Talk to your doctor first before taking either of these supplements, especially if you are pregnant or have a medical condition.

Krill Oil

Krill oil is derived from tiny shrimp-like crustaceans found in the cold waters of the Antarctic. Like fish oil, krill oil is rich in eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA, which are omega-3 polyunsaturated fatty acids. A study published in the "European Journal of Nutrition" in 2013 found that krill oil, which provides omega-3 fatty acids in their phospholipid form, is more effective in lowering triglyceride levels than fish oil. Although it appears that krill oil may be beneficial in helping lower triglyceride levels, alleviating arthritis pain and reducing the risk of heart attack and stroke, more clinical studies involving human participants are needed.

Fish Oil

Fish oil, which has been studied more extensively than krill oil, also provides plenty of omega-3 fatty acids. The authors of a clinical literature review published in the "American Journal of Therapeutics" in 2009 summed up the benefits of taking omega-3 fatty acids in fish oil supplements by stating that they significantly reduce the risks of developing heart disease, lower high triglyceride levels and reduce the risk of clots and irregular heartbeat. An added benefit of taking fish oil supplements is that they eliminate concerns about mercury contamination from consuming fish, which is critical for pregnant and nursing women. One disadvantage of taking a fish oil supplement is it can have a fishy taste and produce fishy-tasting burps. Krill oil doesn't produce those effects.

Comparison of Products

Two popular brands of omega-3 fatty acid supplements are MegaRed Krill Oil and Omega-3 Premium Fish Oil. In general, krill oil is more expensive and may provide less DHA and EPA per capsule than fish oil does. According to MegaRed, one capsule provides 300 milligrams to 1,000 milligrams of krill oil, containing 50 milligrams to 128 milligrams of EPA and 24 milligrams to 60 milligrams of DHA. The Omega-3 Premium Fish Oil label states that a two-capsule serving provides 800 milligrams of EPA, 600 milligrams of DHA and 100 milligrams of other unspecified omega-3 fatty acids.

Other Considerations

Getting your nutrient needs through your diet is preferred, but that's not always possible. If you follow a vegan diet, eating fish is not an option. If you are pregnant or nursing, your doctor may advise you to avoid eating cold-water fish because of possible mercury contamination. Always talk to your doctor before taking krill oil or fish oil supplements to discuss your need for them and the correct dosage, especially if you have a serious medical condition such as diabetes, heart disease or a blood-clotting disorder. Krill oil and fish oil supplements can interfere with anti-coagulation medications by increasing their effects. Don't take krill oil if you have a seafood or shellfish allergy, as cross-reactions are possible.