What is sebum?

Sebum is primarily a mixture of oily substances and fragmented cells produced by sebaceous glands in the skin. This oily secretion plays a crucial role in maintaining skin and hair health, as it acts to lubricate and protect these structures. The lipids present in sebum help to prevent water loss from the skin and also provide a barrier against microbial invasion, thereby contributing to the skin's overall integrity and resilience.

Unlike proteins that provide structural support, sebum is not a protein, which rules out the first option. Additionally, while eccrine glands produce sweat primarily for thermoregulation, they do not create sebum, which means that the option referencing eccrine gland secretion is not accurate. Lastly, while melanin is the pigment responsible for skin color, it does not relate to the composition of sebum, distinguishing it from the correct definition of sebum.