This is usually a subject of controversy but seldom is it refrenced to personal experience. My friend nick delgado, who has been a fitness researcher here in southern california for over 25 years now... Has worked with several companies to find a way to use the miraculous power of stem cells, without using a moraly unsound source. Eventually, and recently he developed a way to extract stem cells from umbilical cords. These tend to be better than the previous way to gather them (which was fairly disgusting and involved fetuses) and also these stem cells are better because they do not contain the dna codings that those which were of the fetus origin had.
This is truly the best treatment I have ever personally witnessed. Restoring everything from skin elasticity (removing wrinkles) to muscle density, bone mass, eyesight, heart problems, nervous system damage, immune system, lung damage.... Anything physical. Ofcourse due to the nature of stem cells themselves, its relative to each individual... However I have never seen anyone who did not have excellent results from umbilical cord stem cells in 2 years of study.