Cod Liver Oil is obtained from the liver of cod fish. Its flavor and aroma range from a mild sardine-like flavor, to an intense odor of fish and oil. High quality cod liver oil is a pale-yellow, thin, oily liquid, having a slightly fishy and bland taste, however some manufacturers add flavors as well. It is rich in vitamin A, vitamin D, EPA, DHA and omega-3 fatty acids. Cod liver oil is widely used for treatment of arthritis. The high vitamin A and D content make it an effective supplement for children for prevention of rickets and for nursing mothers to increase fatty acids and vitamin A in breast milk. It is also effective in treatment of ordinary burns.

Vitamin A is a fat-soluble vitamin with known toxicity. Although its toxicity has been exaggerated, it is a factor worth keeping in mind. Carotine is converted in the human body to Vitamin A, it comes from vegetable sources. Vitamin A is necessary for normal growth and for skeletal development.

Vitamin D is actually a group of prohormones, all fat soluble, whereby ergocalciferol, or Vitamin D2 and cholecalciferol, also known as Vitamin D3 are the most common forms. The Vitamin D3 form is made when human skin is exposed to UV B radiation. The active form of Vitamin D is calcitrol and it is required in the body to manage phosphorus and calcium levels, but, among other functions, to affect anti tumor activity, immunomodulatory functions and much more. Vitamin D, or more accurately calcitrol, is being bound to a carrier protein, which allows it to be transported throughout the body to the various destinations. The Vitamin D receptors, steroid and thyroid hormone receptors, can be found in most organs, including the brain, skin, heart, breast, prostate and gonads.