Found within our skin's sebum, this hydrocarbon helps to prevent water loss (TEWL - trans-epidermal water loss) and acts as an emollient. Squalane is produced naturally by the body, however production slows drastically after the age of 30, potentially contributing to dryness. While they sound very similar, Squalane slightly differs from squalene in it's structure. This difference results in lower stability of squalene, one of the main reasons that squalane is instead used in cosmetic formulations.