What are stretch marks from?

Stretch marks are a type of scar that develop when the skin is stretched too quickly. They are common during pregnancy, puberty, and in people who gain or lose weight rapidly. Stretch marks can also be caused by certain medical conditions, such as Marfan syndrome and Cushing's syndrome.

When the skin is stretched, the elastic fibers in the dermis (the middle layer of the skin) break down. This causes the skin to appear thin and wrinkled. Stretch marks can be red, purple, or white, and they can range in size from small lines to large, wide bands.

Stretch marks are not harmful, but they can be unsightly. There are a number of treatments available to help reduce the appearance of stretch marks, including creams, lasers, and microdermabrasion.