What is it?
Acne is a long-term skin disease. It is characterized by areas of skin with lots of blackheads, whiteheads and pimples. It typically appears during adolescence and it causes significant psychological stress to many teenagers, as people that age are often already self-conscious about their physical appearance and having imperfect skin doesn’t help with their self-esteem.
Acne is very common. It affects about 85% of teenagers, and while its prevalence does decrease with age, about 4% continue to have problems throughout their life.
What causes it?
There is a strong genetic component in the development of acne. Many genes are thought to be involved. Acne probably starts during adolescence because of hormonal changes. Diet seems to play some role but its exact nature is not clear, and cleanliness apparently does not have a significant effect.
What happens during it?
Acne essentially happens when the hair follicles get blocked. There are many possible and often co-existing factors behind this, including the increased secretion of fat into the follicle, too much of the protein keratin in the cells outlining the hair follicle, too many of a species of bacteria called P.acnes living inside the follicles, and the body’s own response to all this which leads to inflammation in the area.
Cells need to be replaced all the time and normally the dead cells that form inside the hair follicles get pushed out of the follicle. In acne, the excessive production of a protein called keratin keeps the cells too tightly together and they start to accumulate inside the follicle. These cells, along with the excess fat produced by the gland that has a duct opening inside the hair follicle, form a sort of plug that prevents anything from getting out of the pore. (An interesting fact: skin color is caused by a pigment called melanin in our skin cells. The more of it we have the darker our skin is. This pigment stays inside the skin cells even after they die. If the plug of dead cells is close to the skin surface, the melanin gets oxidized and turns very dark, resulting in a blackhead. If the plug is deeper down in the follicle this reaction doesn’t happen and a whitehead appears.)
Many hormones, including testosterone, can cause the increased activity of the fat glands. This is thought to lead to the excess production of keratin which makes the dead cells clump together. This is also thought to make the environment inside the follicles ideal for the naturally occurring P.acnes bacteria, and as they increase rapidly in number, the body notices that something’s wrong and starts an immune reaction. Inflammation is promoted in that area to encourage more white cells to travel there through dilating the blood vessels and making them more permeable – this causes the redness and pain associated with acne.
How can it be treated?
There are lots of ways to treat acne. It’s recommended to avoid eating simple sugars. Medications can work through, for example, killing the P.acnes bacteria, reducing fat production, normalizing the process of how the cells lining the follicles live and die, and reducing inflammation. In women it might be helpful to use a combined oral contraceptive, as it reduces the amount of acne-causing hormones that are normally produced in the body.
Sources: en.wikipedia.org/wiki/Acne_vulgaris, https://en.wikipedia.org/wiki/Hyperkeratinization, en.wikipedia.org/wiki/Sebaceous_gland, https://en.wikipedia.org/wiki/Biofilm, https://en.wikipedia.org/wiki/Propionibacterium_acnes