Beauty education

Primary causes of acne

Elise Deylgat

Hormonal acne, also known as ‘acne’ or ‘acne vulgaris’ is one of the most common skin concerns worldwide. This skin condition varies from small comedones and pimples to severe inflammatory lesions. For most people acne manifests for the first time during puberty. Eighty-five percent of people, aged between 12 and 24, suffer from acne1. Usually, it disappears spontaneously around the age of 25. Nevertheless, the condition can be persistent and some people still suffer from the condition in adulthood. In this blog we will elaborate on the causes of acne and the role of lifestyle factors.





Acne is a multifactorial disease and is influenced by 4 primary factors: (i) increased sebum production; (ii) hyperkeratinisation of the upper skin layer; (iii) growth of the P. acnes bacteria and (iv) inflammation

The onset of acne is initiated by increased sebum production and hyperkeratinisation of the dead skin cells:

  • Sebum is an oily substance secreted by the sebaceous glands in our skin and protects the skin against dehydration and external factors. An increased production of this fatty substance can cause a pore blockage, resulting in microcomedones or small pimples. Hormones play a role in the development of acne as they regulate the production of sebum. Increased hormonal activity (mainly male hormones / androgens) can therefore lead to increased sebum production. Your hormone levels may alter during certain phases of your life (for example: menstrual cycle, puberty, pregnancy, illness) and as a result you may experience more acne breakouts at certain moments.


  • Hyperkeratinisation is a second important element in the development of acne. Let's explain this process of ‘hyperkeratinisation’ briefly: Our skin renews itself every 28 days. During this renewal process, new skin cells migrate from the bottom to the surface of the skin. The skin cells undergo a change in shape and composition during their migration to the surface of the skin. The upper cells are called ‘corneocytes' and consist of old, dead skin cells that flake off the skin. In this way, new cells can migrate to the surface. So, new cells are constantly being created and old cells are constantly flaking off. With hyperkeratinisation, there is an insufficient exfoliation (shedding of) of the dead skin cells. The corneocytes stick to the skin's surface and there is an accumulation of these old skin cells. The combination of hyperkeratinisation and increased sebum production results in the blockage of the pores and the development of primary acne lesions.

Once formed, a microcomedone can evolve into a non-inflammatory comedone, such as blackheads and whiteheads.

  • These primary acne lesions, rich in lipids, form an ideal growth medium for the anaerobic Propionibacterium Acnes bacteria. This bacterium is always present on the skin but can thrive under certain circumstances (ideally an oxygen-poor culture medium such as sebum).
  • Due to the presence of large numbers of this type of bacterium, your immune system starts to react and the generation of inflammatory mediators initiates the development of inflammatory lesions. Inflammation therefore results in pimples, papules, painful lesions, which, if left untreated, can lead to acne scars.

Different treatments can be used depending on the severity, location and type of your acne. Drugs to treat acne always act on 1 or more of these primary factors. Moreover, acne can also be initiated by other 'secondary' or lifestyle factors. Read more about these lifestyle factors and acne treatments on our blog pages soon.