In some cases, they persist into adulthood but the mechanisms at play in adult acne are quite different. We are going to explore the age at which acne starts, its causes, the typical forms in adolescence, and the aggravating factors.


At what age does acne start?

Acne begins during puberty and varies depending on the individual. It is triggered by the production of sex hormones, which depends on several biological and environmental factors. Girls and boys are not necessarily affected at the same age or in the same places.

In general, there are pimples and blackheads on the face and the areas with the most sebaceous glands, i.e. the upper back, cleavage, and T-zone.


Where do pimples come from?

Sex hormones are responsible for numerous physical changes in adolescence, especially in the functioning of the sebaceous glands.

  • Temporarily active at birth under the influence of the mother’s hormones which are passed on to the child at the end of pregnancy, the sebaceous glands are at rest between the ages of six months and nine or ten years and are then reactivated during puberty. They start to produce a large quantity of sebum, which is typically evacuated through hair ducts.
  • In parallel, dysseborrhoea alters the composition of sebum, and squalene becomes oxidised. It then thickens. As a result, skin pores become clogged. Blackheads and pimples then appear when the excess sebum is no longer able to flow through the pilo-sebaceous follicle as usual. This sebum blocks the hair duct and becomes trapped, initially forming a comedo. Bacteria multiply inside the comedo and contribute to the development of pimples.
  • Heredity should also be taken into account. The family factor alone can probably not explain why acne occurs, but it can provide insight as to its severity. If both parents have had acne, the risk for the children is higher. The characteristics of sebum have a genetic component, although there are several other related factors involved.


What are the typical forms of adolescent acne?

Adolescent acne is polymorphous, comedonal and inflammatory, caused by the accumulation of sebum that cannot be evacuated. There are two types of blemishes:

1: Open comedones, commonly called “blackheads”
2 / 3: Skin-coloured closed comedones or microcysts (causing the skin to appear grainy when seen in profile using low-angle lighting)
In both cases, the blemishes promote bacterial (C. acnes) proliferation, causing follicular inflammation and progression to inflammatory acne.

Acne Teen schema

Picto Phone in Hand

Several lifestyle aspects can have a negative impact on acne, including the cosmetic products used, make-up, the sun, diet, and the use of a mobile phone in particular.

Hygiene and cosmetic care

This is particularly important. Bacterial proliferation aggravates acne, which is why the skin needs to be thoroughly cleansed on a daily basis. But it should not be stripped!

  • People with acne-prone skin should choose products that have been specifically formulated to prevent blemishes, such as foaming gels or micellar waters.
  • Make-up removal is an essential step for all women, but especially those combating pimples and blackheads.
  • When it comes to choosing make-up, watch out for high-coverage foundations and powders, which risk causing pimples. ‘Acne cosmetica’ is the term used by dermatologists to refer to acne that has been caused or aggravated by cosmetics.

The sun is most certainly not an ally for problem skin, even though it tends to dry out lesions at first. In reality, sun exposure thickens the skin, causing blemishes to be less visible. When the summer is over, patients experience the dreaded rebound effect, which is when numerous pimples reappear simultaneously. People with acne should therefore avoid over-exposure to UV rays. There are multiple sun care products that have been designed to protect acne-prone skin. Whether tinted or not, they can provide a matte finish and are capable of protecting and treating at the same time.

Back of a woman under the sun

Diet has long been suspected of playing a role in acne. Studies are currently in progress to scientifically validate various hypotheses, but it is known that some people can reduce their acne by eliminating dairy products from their diet. Some experts claim that industrial processed foods high in fat and sugar, which tend to be very common in the diet of teenagers, contribute to the development of acne. So while it’s fine to eat burgers and tacos from time to time, they should be part of a balanced diet consisting of lots of fresh fruits and vegetables. Also remember to drink plenty of water, which has multiple health benefits for the skin.

Your Skin - Healthy food

Mobile phones are an integral part of life for adolescents but are also highly effective bacterial vectors. They should thus be cleaned on a regular basis, keeping in mind that they are often stored in or placed on dirty surfaces (handbags, pockets, bar tables, floor for recharging, etc.). You can also use earphones or headphones to keep your phone from touching your cheeks.

Man working with a laptop and a mobile phone