Premature skin aging can involve extra blood vessels, brown spots, fine lines and wrinkles, different color of the skin as a yellow, sallow color, and cobblestoning of the surface. Many of these changes are related to the earlier years of sunexposure that one has had, especially the ultraviolet A rays that penetrate deeper than the UV-B rays. The texutural change is permanent, whereas some of the coloration changes can improve with religious avoidance of sunexposure and the use of sunscreen. Topical vitamin A, Retin A (tretinoin) can improve the skin's condition with long term use and sunprotection techniques. Other topicals use naturally found ingredients, such as Elure's lignin peroxidase which has been found to lighten skin after discovering the chemical in fungi growing against tree trunks that caused a lighter color in the bark. Revale and TNS Essential serum use antioxidants, the former using a coffee berry extract.
Lasers, of course, such as Fraxel and plasma devices such as Portrait, and ultrasonic treatment such as Ultherapy, and radiofrequency devices such as Thermage and Pelleve, can all help but these are not "natural." If you want to avoid all unnatural treatments and products, then you just have to be patient, avoid all sun exposure and allow the skin cell defenses to help reverse some coloration issues.