Oily skin

<How do skin blemishes originate?>

Three associated factors are responsible: hyperseborrhoea, hyperkeratinisation and bacterial proliferation.

• Hyperseborrhoea: this is the overproduction of sebum resulting from the hormonal activity triggered at puberty. The skin becomes oily and shiny.

• Hyperkeratinisation: the excessive proliferation of skin cells leads to the formation of a plug that prevents the sebum from being discharged. These plugs are comedones, known as "blackheads" when they are open and microcysts when they are closed.

• Bacterial proliferation: sebum provides the ideal nutritional environment for certain bacteria, in particular, Propionibacterium acnes. The latter multiplies in the pilosebaceous follicle where it causes inflammation. The blackhead is then transformed into a painful red spot called a papule.