How to recognise the different types of skin imperfections?

Until now, it is still commonly believed that poor daily hygiene is the main cause of these skin issues. However, this is not always the case. Other triggering factors, whether internal or external, can contribute to a blemished skin, such as:

• Hereditary predisposition: Genetics and family history appear to play a dominant role in the onset of acne, particularly severe acne. Indeed, several studies show that acne appears earlier and is more severe in individuals with positive family histories. One study even identified two new loci, 11p11.2 and 1q24.2, which are thought to be involved in the metabolism of androgens, inflammatory processes, and scar formation in severe acne, thus highlighting another risk factor influencing acne.

  There is also a clear genetic predisposition in patients suffering from melasma, a common form of hyperpigmentation. Indeed, 60% of those affected report that family members also suffer from it. Similarly, genetics predominantly determine the size of skin pores;

• Skin Type: Combination to oily skin types are most likely to exhibit blemishes such as blackheads, comedones or pimples, as they secrete more sebum than normal, creating a favourable environment. Of course, they can also appear on other skin types under the influence of several factors;

• Aging: As we age, the skin loses its elasticity, thus the skin around the pores becomes less tight, which can then lead to an increase in their size and make them more visible.

  Furthermore, as we age, the skin's cellular renewal process slows down. Consequently, dead cells remain on the skin's surface instead of shedding, leading to their accumulation, the blockage of pores (and also their enlargement), and thus the formation of spots;

• Hormonal Disorders: Hormones are one of the main causes of skin imperfections. For instance, during puberty, the body produces more male hormones (testosterone, androgen), which in turn boosts the production of sebum in the sebaceous glands. As a result, men tend to suffer more from acne during adolescence than women. However, in adulthood, women are more affected by acne than men, which can be largely attributed to a hormonal component.

  Although their levels stabilise over the years in men, in women, they continue to fluctuate, particularly with the onset of menstruation (premenstrual syndrome), during pregnancy, at menopause or even following the cessation of hormonal contraception. A study has shown that a high serum level of progesterone, but a low level of oestrogen, was found in patients suffering from common acne.

  UV rays are not the only factors that promote the appearance of brown spots on the skin. Hormonal factors also play a role in skin pigmentation defects. Studies have shown that under the influence of female hormones, namely oestrogen and progesterone, an over-stimulation of melanocytes has been observed;

• Chronic sun exposure: Overexposure to the sun can cause dehydration and dry out the skin. In response to this imbalance, the skin will start to produce more sebum. Similarly, indirectly, the sun is also a risk factor in the dilation of skin pores. It weakens the structure of the dermis, damaging the collagen and elastin fibres. Less firm and flexible, the dermal structure surrounding the pores then collapses and their size widens.

  Ultraviolet rays also constitute the main exogenous factor capable of altering the normal pigmentation of the skin. In response to the mutagenic effects of the sun's UV rays, the skin secretes melanin to protect the nucleus, and therefore the DNA, of the keratinocytes in the basal layers of the epidermis, acting as a natural sunscreen. Furthermore, the penetration of the sun's UV rays leads to an increased production of free radicals, which would stimulate the production of melanin to protect cells from their harmful effect;

• Imbalanced Diet: There is evidence that diet can promote the development of acne. Indeed, studies have assessed the impact of the glycaemic index of various foods on the skin, revealing that individuals following a high glycaemic load diet have more acne lesions. This is caused by a significant production of insulin to lower blood sugar levels, which in turn increases androgen levels, thereby promoting sebum secretion.

  Similarly, several studies have demonstrated a positive association between the consumption of dairy products and the prevalence of acne. More specifically, they have shown that whey proteins and casein could contribute to the development or exacerbation of acne, by triggering sebum production. Furthermore, acne can be caused by the consumption of foods high in free fatty acids, which can promote the proliferation of P. acnes .

• Sleep Quality: A sleep duration of less than 8 hours per day could be a risk factor for acne. Indeed, studies have shown that a lack of sleep (sleep duration ≤ 5 hours) was correlated with an increase in transepidermal water loss compared to individuals with good sleep quality (sleep duration between 7 - 9 hours), indicating an impairment of the skin barrier. In such a situation, the skin's defence system against external aggressions is weakened, which can lead to skin problems such as acne, but also an increase in sebum production;

• Touching the face: Generally, we touch our face about 3,000 times a day, although this varies from person to person. However, our hands come into contact with numerous surfaces throughout the day that harbour bacteria and other dirt that is not good for the skin. This can potentially lead to an increase in skin imperfections. Similarly, handling and popping pimples significantly increases the risk of damaging the skin and thus promoting the formation of scars.