All about Acne
Acne is a skin disorder that usually appears in adolescence and causes blackheads and pimples. Acne can leave scars and have psychological repercussions. Therefore, it is important to treat it early.
What Causes Acne?
There are four basic factors that lead to the development of acne lesions:
- Follicular Hyperkeratinization: Hair follicles are blocked by excess normal skin cells (the so-called keratinocytes), which combine with the sebum secreted by the sebaceous gland and form a plug that blocks the hair follicle.
- Increase in the production of sebum: Sebaceous glands, which are more abundant in face, neck, chest, upper back and upper arms, grow larger and increase their sebum production. One of the causes of this stimulation is the presence of androgens, the male sex hormone, which level increases during puberty.
- Growth of Cutibacterium acnes: The increase in the production of sebum favors the growth of a bacterium called Cutibacterium acnes, which is part of the set of bacteria living in the pilosebaceous follicles of healthy skin, since sebum is its source of nutrients. The excessive increase of this type of bacteria breaks the balance of skin flora, favoring the occurrence of inflammation.
- Inflammation: Inflammation may cause the follicle to rupture, leading to the formation of a red pimple, also called "tender".
Factors Involved in the Occurrence of Acne:
The main causes for the development of acne are:
- Androgens: Based on clinical observations, the presence of androgens affects the development of acne. In fact, acne does not usually develop before the prepuberal period, also known as adrenarche, i.e. the moment when the levels of dehydroepiandrosterone sulfate (DHEAS) increase. DHEAS is a male sexual hormone (androgen), which is present in both men and women and plays a significant role during puberty in the development of male secondary sexual characteristics. The body can turn DHEAS into more powerful androgens, like testosterone and androstenedione, and can also turn into the female hormone estrogen. In pathologies with high levels of androgen, as in the case of polycystic ovarian syndrome, congenital adrenal hyperplasia, or adrenal or ovarian tumors, this increase in androgens may be the cause of acne.
- Cutibacterium acnes: Critical factors that may be involved in the close association between this bacterium and the development of acne include its ability to activate the response of the immune system, which may contribute to the occurrence of the inflammation often observed in acne.
- Genetic Factors: People with close relatives who have acne are at a higher risk of developing it, supporting the idea that the disease has a genetic component.
Other risk factors that may contribute to its development are:
- Skin Trauma: A mechanical, repetitive trauma, like that caused by washing affected skin with soap, detergent, astringent or other agents, may worsen acne because it may favor the rupture of comedones, causing the appearance of inflammatory lesions.
- Food Habits: Results from several studies suggest that there may be an association between the development of acne and a high consumption of milk and dairy products. Likewise, a relationship has been established between the occurrence of acne and diets with a high glycemic load, such as pasta, bread, cookies, sugary cereals, white rice or watermelon. These types of food raise levels of a substance called insulin-like growth factor (IGF), which may favor the development of acne. proven. Some foods have been related with positive effects, such as zinc, omega-3 acids, antioxidants, vitamin A, and food fiber, although more studies are needed to confirm this.
- Stress: One possible factor that has been suggested to intensify acne is the presence of psychological stress.
- Insulin Resistance: Insulin resistance might also be one of the factors favoring the occurrence of acne, since it can stimulate a higher production of androgens, and it is associated with higher levels of blood in insulin-like growth factor 1 (IGF-1), which is related with a larger secretion of facial sebum. During puberty, there is an abnormal increase in insulin resistance and IGF-1, which is also the onset of acne.
- Increased Body Mass Index (BMI): Studies have been conducted to examine a potential relationship between weight and acne, but results have been different, in a way that an association between overweight or underweight and the development of acne cannot be confirmed.
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