What are stretch marks?

Tearing of dermis: When skin stretches rapidly like with pregnancy or weight gain the top layer or dermis can tear. When this happens it becomes discolored in some individuals causing stretch marks.

Stretch Marks: Stretch marks happen when the skin is pulled by rapid growth or stretching. Although the skin is usually fairly elastic, when it's overstretched, the normal production of collagen (the major protein that makes up the connective tissue in your skin) is disrupted. As a result, scars called stretch marks may form.

Skin tears: Stretch marks are tears in the skin cause by weight gain. They can be covered up, but not improved by creams and lotions. The only possibly effective therapy is cosmetic plastic surgery, but that's a big step for a non-health and non-life threatening problem.