Cod liver oil is exactly what it says it is, oil from the liver of a cod! It is a rich source of both Omega-3 & vitamin D. Did you know adults should aim to eat at least 2 portions of fish each week with one of them being oily? Our Cod Liver Oil One-a-day product comes in the form of an easy to consume, single capsule dosage for those important health benefits we need every day. It contains 120 mg of Omega-3 plus the Government recommended, 10 μg vitamin D.