Cod liver oil is a nutritional supplement derived from the liver of cod fish. It is rich in omega-3 fatty acids, which are essential for heart and brain health. Additionally, it contains vitamins A and D, important for maintaining healthy vision, immune function, and bone health. People often take cod liver oil to support overall wellness and to help reduce inflammation. It can be consumed in liquid form or as soft gel capsules. While it offers various health benefits, it's important to use it in moderation, as excessive intake can lead to toxicity due to high vitamin A levels.