Why do we get blackheads and acne?

The skin's production of sebum can cause pores to become clogged, leading to blackheads and sometimes even acne. The sebum that is formed can also disrupt the normal maturation process of the skin's cells (keratinocytes), i.e. their differentiation and exfoliation process, which further affects the risk of clogging the pores.

When the skin produces too much sebum and does not slough off the dead skin cells quickly enough, the hair follicles can build up, causing a plug to form. This plug can cause the follicle to swell and form a white pore or, if the plug is open on the surface, form a dark or black pore. A common misconception is that the black blackhead is due to impure skin and that the black is dirt. This is not the case, but it is simply the skin's pigment (melanin) that oxidizes and turns dark when open pores come into contact with the oxygen in the air.

The reason that the area around the blackheads becomes inflamed is often that bacteria and fungi like the oily environment around the blackheads and grow. This can lead to wart formation and also inflammation of the skin around the pimple (papules/pustules).

A blockage or inflammation that develops deep in the sebaceous glands can form lumps under the surface of the skin called cysts.

Causes of blackheads and acne

Hormonal influence

Testosterone or other androgenic hormones stimulate the sebaceous glands to produce more sebum (sebum) than is necessary. During puberty, hormonal changes occur in both boys and girls, and the sebaceous gland, which is sensitive to these hormonal changes, then produces more sebum. Oily skin is therefore a very common skin condition during puberty or the years after, which increases the tendency to get blackheads and acne.

Hereditary influence

There is some evidence that heredity plays a large role in the development of blackheads and acne. If both parents have suffered from acne during puberty, it is likely that their children will also develop acne.

Diet and skin care products

Although the main causes of acne-prone skin tend to be hormonal or hereditary, there are a few other factors that have been shown to worsen symptoms; this mainly applies to diet and various skin care products. When it comes to diet, a lot is individual, but there are studies that show that certain foods in combination with oily skin give an increased risk of acne. However, we always recommend that you do not change your diet alone, but combine it with a medical treatment if you suffer from acne that requires medical treatment. This is to minimize the risk of scarring.

In addition to hereditary factors, the following factors have been shown to influence acne symptoms.

• A high consumption of milk can worsen acne symptoms. Several studies show that there is a relationship between milk drinking and acne (Aghasi et al., 2019; Dai et al., 2018). However, the same connection has not been seen with cheese and yogurt.
• A diet rich in certain carbohydrates: There is compelling evidence that foods with a high glycemic index (GI) and milk can trigger acne. Both are known to stimulate androgens (male hormones) which play an important and proven role in the development of pimples.
• Vitamin D: A recent study found that 28% of acne patients are deficient in vitamin D compared to control subjects where only just under 7% were deficient. The lower the levels of vitamin D the subjects had, the more severe the degree of acne (Singh et al., 2021). However, it is unclear whether intake of vitamin D-rich diet has any effect on acne-affected skin.
• Oilier creams or comedogenic skin care products and make-up (primarily foundation) can, through their occlusive ability, clog pores and in this way trigger acne breakouts

Tips for not making your acne worse

It is always good to consult a dermatologist, even for mild and early symptoms (to prevent the condition from getting worse), but there are certain rules that are good to follow;

• Leave the pimples alone - do not touch or squeeze them, this increases the risk of worsening inflammation and an even worse condition
• If you feel that you have cysts under the skin or if the pimples do not heal normally or form scars, it is important that you get medical help. Diagnosed acne may require medical treatment in the form of isotretionine or other drug treatment. Scars are unfortunately difficult to do anything about once they have appeared and therefore it is important to start medical treatment in time.
• Use non-comedogenic makeup, i.e. makeup that does not clog pores.
• Use non-comedogenic skin care, i.e. skin care that does not clog pores.
• Use sunscreen designed for oily and acne-prone skin. Preferably avoid skin care/make-up with sunscreen during the winter months (in Sweden) - exceptions are the mountains (high altitude) or when the sun is reflected against the snow.

Contrary to what all the myths claim, toothpaste does not help dry out rashes. There is no medical evidence to suggest that they help in any way. In fact, toothpaste contains substances that can irritate and damage the skin.

More information in the Skin Bible

The Skin Bible contains more tips regarding diet and acne-affected skin.