When Retin A is applied to the skin it penetrates to the deeper layers of the dermis. The following changes are seen:
There is an increased activity of the basal cells which causes an increase in their number and improvement in their shape and organization. This leads to a thicker, more level skin surface with less wrinkling.
With this increase in new cell production there is less clumping of old cells on the skin's surface, this further improving the texture and smoothness of the skin.
In the dermis, there is increased production and improved organization of new collagen fibers. This leads to thicker, more supple and les wrinkled skin.
Blood vessel growth is stimulated, this leading to better circulation. This might also account for the slight blush or pinkness which is often seen wit the use of vitamin A.
The melanin pigment of the skin tends to be disbursed faster, moving upwards and outwards as a result of the increased rate of cell turnover. This leads to less prominent and fewer freckles, sun spots and bothiness.