Retinoids are derivatives of Vitamin A, skin product options include retinoic acids (prescription tretinoin, Retin-A, Renova, etc), retinol (milder retinoic alcohol), and retinaldehyde (Retrinal brand from Avene, France). Retinoids help to normalize abnormal microscopic cell growth, decreasing the incidence of precancerous keratoses. They exfoliate the top layer of the epidermis, help to empty clogged pores, smooth the skin, lighten superficial brown spots, help other topical medications and products penetrate deeper, and generally give the skin improved color and tone. Retinoids also have an effect on the dermal skin layer, by stimulating the production of new collagen and elastic tissue, thereby improving the infrastructure of the skin and softening fine lines and wrinkles.