Study Comparing Fish Oil and Krill Oil

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are omega-3 fatty acids found in fish oil and in krill oil. The purpose of this study is to compare the effects of the recommended dose of a fish oil supplement (Omax3 4:1 EPA:DHA; recommended daily dose 1650 mg - totaling 1500 mg EPA+DHA) and a krill oil supplement (MegaRed; recommended daily dose 300 mg - totaling 74 mg EPA+DHA) on omega-3 index, plasma biomarkers of inflammation and inflammatory cell activation, and plasma lipid levels in subjects with metabolic syndrome.

Inflammation plays a pivotal role in the pathogenesis of several chronic diseases including cardiovascular disease and diabetes mellitus. There has been some evidence that fish oil, containing the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), reduces the risk or severity of these diseases, leading several government and health organizations to advocate an increased consumption of fish or fish oil. Fish oil contains EPA and DHA either as triglycerides or as ethyl esters. Recently, krill oil has gained popularity as an EPA and DHA supplement. Krill oil contains EPA and DHA in phospholipid, triglyceride, and free fatty acid form. Some studies have shown that the bioavailability of EPA and DHA in krill oil is higher than in fish oil and that smaller doses of krill oil are therefore sufficient to observe a significant effect on the desired outcome (inflammation, plasma lipid levels). The central hypothesis of this proposal is that the dose of the EPA and DHA omega-3 fatty acids is more important than their bioavailability in effecting changes in systemic inflammation and lipid metabolism.

fish oil, 1500 mg/day, EPA:DHA ratio of 4:1, each capsule containing 750 mg total EPA+DHA, 2 capsules/day for 10 weeks

Inclusion Criteria: fasting plasma triglyceride levels between 150 and 500 mg/dL C-reactive protein (CRP) levels ≥2 µg/mL at least one of the following criteria for the definition of metabolic syndrome: abdominal obesity (waist circumference >40 inches in men and >35 inches in women), hypertension (blood pressure ≥130/≥85 mmHg or use of anti-hypertensive medications), and fasting glucose ≥110 mg/dL. Exclusion Criteria: high-fish diets (>2 fish meals/week) taking fish oil supplements or supplements containing EPA or DHA regular use of anti-inflammatory medications Above normal coagulation time or use of anticoagulant medications allergy to fish, fish oil, or shellfish uncontrolled thyroid dysfunction insulin-dependent type 2 diabetes mellitus kidney or liver disease smoking drinking more than 7 alcoholic drinks/week use of lipid-lowering medications or medications known to alter lipoprotein metabolism