Why Stretch Marks Occur

Partially due to genetics, stretch marks are small tears in the dermis that result when the fat or muscle beneath the skin is growing at a faster rate than the skin itself. “Keeping the skin moisturized during periods of ‘stretching,’ such as pregnancy, may help prevent them from forming,” says San Antonio plastic surgeon Mark W. Greene, MD. If your weight is fairly steady, you may be less likely to develop stretch marks, but there’s no guarantee that they won’t form. 

Unsightly stretch marks may be an inevitable fact of life, since there is a genetic component to them, but you may be able to minimize their appearance with the right plan of attack. “While we haven’t found a method that 100-percent prevents or eliminates them, there are some technologies that may help to lighten up the redness associated with some stretch marks, making them less apparent,” says Montclair, NJ, plastic surgeon Barry DiBernardo, MD. Read more about treating stretch marks here.

Stretch Mark Summary:

Changes in Collagen
As the tissue under the skin is “stretched out,” normal collagen production is interrupted, and stretch marks begin to surface.

Textural Changes
“Stretch marks can cause problems in terms of skin texture because the tissue has collagen that is laid down in layers, in one direction as a scar,” says New York dermatologist Macrene Alexiades-Armenakas. “As a result, the skin is atrophic or thin, and the light reflected makes them appear white.” 

Elevated Hormone Levels
Stretch marks also correlate to an influx of the hormone glucocorticoid, which becomes elevated during puberty, pregnancy, excessive weight training and obesity, and prevents collagen and elastin from properly forming.