Sebum

Lipid substance produced by sebaceous glands, composed of triglycerides, wax, squalene and free fatty acids. It forms a protective film on the skin surface and participates in regulating the cutaneous microbiome. Its overproduction (hyperseborrhoea) is linked to excess androgens, IGF-1 and activation of the mTORC1 pathway. Regulated by zinc, niacinamide and a low glycaemic index diet.