Shark liver oil in concentration of 0.4 - 0.7 %. However, liver of the deep sea shark forms the richest source of natural squalene. Shark liver oil consists of about 60-85 % of this organic matter. It is generally assumed that squalene is essential substance from the very beginning of life that explains the presence of high concentration of squalene in new born babies, responsible for their soft skin, and such babies need to strengthen the immune system in no time after birth.