Why do we get blackheads and acne?

Skin production of sebum can cause pores to clog, leading to blackheads and sometimes even acne. The sebum that is formed can also interfere with the normal maturation process of skin cells (keratinocytes), i.e. their differentiation and de-scaling process, which further affects the risk of pores clogging.

When the skin produces too much sebum and does not peel off the dead skin cells quickly enough, there can be a build-up of hair follicles, which causes a clot to form. This stopper can cause the hair follicle to swell and form a white blackhead or, if the stopper is open on the surface, form a dark or black blackhead. A common misconception is that the black blackhead is due to the fact that the skin is unclean and that the black is dirt. This is not the case, but it is simply skin pigment (melanin) that oxidizes and becomes dark when open pores come into contact with the oxygen of the air.

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

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

Causes of blackheads and acne

Hormonal impact

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

Hereditary influence

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

Diet and skincare products

Although the main causes of acne-prone skin tend to be hormonal or hereditary, there are a couple of other factors that have been seen can exacerbate symptoms; this applies above all to diet and various skin care products. When it comes to diet, it is very individual, but there are studies that show that certain foods combined with oily skin increase the risk of acne. However, we always recommend not only changing your diet but combining it with a medical treatment if you suffer from acne that requires medical treatment. This is to minimize the risk of scarring.

The following factors have been shown to affect acne symptoms in addition to hereditary factors.

• A high consumption of milk can worsen acne symptoms. Several studies show that there is one between milk drinking and acne (Aghasi et al., 2019; Dai et al., 2018). However, the same connection to cheese and yogurt has not been seen.
• A diet rich in certain carbohydrates: There is compelling evidence that food with a high glycemic index (GI) and milk can trigger acne. Both are known to stimulate androgens (male hormones) that play an important and proven role in the development of pimples.
• Vitamin D: A new study showed that 28% of patients with acne have a deficiency of vitamin D compared to the control subjects where only just under 7% had a deficiency. The lower the levels of vitamin D subjects had, the more severe the degree of acne (Singh et al., 2021). However, it is unclear whether the intake of vitamin D rich diet has any effect on acne-affected skin.
• Oily creams or comedogenic skincare products and makeup (mainly foundation) can clog pores due to their occlusive properties and thus trigger acne breakouts.

Tips to avoid aggravating your acne

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

• Do not touch or pinch the pimples, it increases the risk of worsening inflammation and an even worse condition
• If you feel that you have cysts under your 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 isotretionin or other drug treatment. Unfortunately, scars are difficult to do anything about once it has arisen and therefore it is important to put in medical treatment on time.
• Use non-comedogenegenic makeup, i.e. make-up that does not clog the pores.
• Use non-comedogenic skin care, i.e. skin care that does not clog pores.
• Use sunscreen designed for oily and acne-prone skin. Avoid skin care/make-up with sun protection 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 myths claim, toothpaste does not help to 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

In the Skin Bible there are more tips regarding diet and acne-ridden skin.