Metabolic Impact of VLCPUFA-Rich Fish Oil: A Clinical Study on Omega-3 Index Enhancement in Healthy Individuals

Background: Fish oils contain omega-3 fatty acids that play important roles in the body. Researchers are studying a new type of fish oil that contains very-long-chain omega-3 fatty acids (VLCPUFAs). They want to learn how this fish oil affects omega-3 levels in the blood and other measures related to health. Objective: To learn how a VLCPUFA-enriched fish oil changes omega-3 levels in the blood compared with a standard fish oil. Eligibility: Healthy adults ages 18 to 60 years with a body mass index (BMI) between 18 and 30 kg/m\^2 may be eligible. Design: Participants will take part in the study for about 28 to 30 weeks and will have approximately 4 to 5 clinic visits plus a follow-up phone call. Participants will complete screening tests to determine whether they are eligible. These may include a physical examination, blood tests, measurement of height and weight, visual testing, cognitive testing, and questions about their diet, exercise, medications, and daily habits. Participants will take 2 fish oil capsules by mouth every day for 8 weeks. They will then stop taking study capsules for about 12 weeks. After that, they will take a different fish oil capsule for another 8 weeks. One fish oil contains very-long-chain omega-3 fatty acids (VLCPUFAs), and the other contains standard omega-3 fatty acids. Participants will not know which type they are taking during each study period. Blood samples and other study assessments will be collected at the beginning and end of each treatment period to measure changes in omega-3 levels and other study markers. Participants will receive a follow-up phone call about one week after taking their last dose of study supplement.

* INCLUSION CRITERIA In order to be eligible to participate in this study, an individual must meet all the following criteria: 1. Male or female, age 18-60 years, in good general health in accordance with PI evaluation. 2. Body Mass Index (BMI) \>18 and \