Aging, or rather, how to avoid it, has intrigued mankind from the earliest times. It has been a quest comparable to the alchemists’ search for a way to turn lead into gold. Just as the alchemists spawned chemistry the quest for the fountain of youth has led to a large body of research into aging. Among the many theories on the nature of aging the oxidative stress hypothesis is the most plausible one. This theory states that the lifelong accumulation of oxidative damage to biological macromolecules such as proteins, DNA and lipids is the mechanism underlying aging. Considering that DNA contains all the information needed to build and maintain a cell, it is surmised that (oxidative) damage to DNA is the predominant contributor to aging. In support of this idea are the accelerated segmental aging phenotypes of humans and mice with defects in DNA repair mechanisms.