Squalene is an oil which is derived from both plant and animal sources. Small amounts of squalene are produced by the human body and can also found in many vegetable oils. Much larger quantities of squalene can be derived from certain fish oils. Squalene is a natural and vital part of the synthesis of cholesterol, steroid hormones and vitamin D. The most common and valuable source of squalene is found in the livers of deep–sea sharks.
Squalene is a low–density compound often stored in the bodies of cartilaginous fish, such as sharks, which lack a swim bladder and therefore must reduce their body density with oils and fats. Squalene is mainly stored in the shark’s liver.