What Causes Stretch Marks?
The most common reason stretch marks occur is because the skin changes shape too rapidly. This sudden change, whether through weight loss or excessive weight gain, causes a tear in the middle layer of your skin, the dermis. The collagen and elastin fibers in the dermis rupture and you end up with "underground" scars that look like stripes on the affected area. In their earliest state they are red, purple, pink, or brown, depending on the color of your skin. However, they gradually turn a dull silvery gray or white color.
Pregnancy and puberty are also common times that one may be more likely to see stretch marks. Stretch marks occur during this time because your skin is expanding as your body matures and changes. Stretch marks can occur nearly anywhere on the body; common sites include the breast, abdomen, buttock, and arm areas. However, the most important thing to remember is that the sooner you treat them, the better your chances of removing and/or lessening them