Scientific research has identified a variety of factors that affect extrinsic and intrinsic aging of the skin. Many of these factors are controllable by simply modifying your behavior and diet. This section covers ways to prevent skin aging, and the following sections cover ways to treat it.

Sunlight is the major cause of extrinsic skin aging and skin cancer. It damages collagen and elastin and can cause changes in cells that trigger cancer. Doctors call this type of skin aging photoaging, that is, aging produced by light.

You should not expect the texture of the epidermis to be porcelain-smooth. The openings of the pores and sweat glands cause small indentations, and there are small ridges covering the surface. Many people have a false sense of how smooth adult skin should appear because they see models and celebrities who seem to have perfect skin in magazine photos, on TV and in movies.

Only children or people who have generally avoided sun exposure have this type of skin. Most close-up magazine photos are touched-up to smooth skin texture, and both men and women wear a lot of makeup on TV and in the movies. (There is a web site with candid photos showing that many celebrities have the same skin problems as everyone else.)

You can buy medical-grade silicone sheets for scar treatment that are taped over moderately-raised scars to flatten them over time (however, they won't work on keloid scars.) They may also help flatten uneven areas from second-degree burns. There are many medical studies that show this method improves the appearance of new scars, though the mechanism is unknown.

Wounds or surgical incisions that penetrate into, or through, the lower dermis are likely to cause scars. The scars that form are classified as hypertrophic (raised) or atrophic (depressed or flat). Keloid scars are hypertrophic scars with especially hard and prominent tissue. Following a wound, it can take a year or more for the scarred skin to fully heal.

Accutane dosage is calculated by your body weight, however, some research indicates that daily dosage can be reduced so long as the total accumulated dose over the course of treatment (that is, the number of pills taken) is the same. So you can reduce the risks of taking Accutane by starting out with a low daily dose to see if there are any serious side effects.