The official Revitol website needs some work.

[tarakul islam]

The blurb says that Revitol helps to increase the production of
collagen and elastin. Of collagen, this may be true. But elastin is an
immutable, very tough protein no longer produced after puberty. If
elastin is added to Revitol, fine. But it states that Revitol
stimulates the body’s production of elastin. According to the
textbooks on any dermatologist’s shelf, elastin can be replicated only
early on, only in the bodies of children.
http://stretchmarkinstitute.com/products/1,revitol-stretch-mark.html