The current issue of Scientific American contains a brief story written at the lay level about a scientist named David Gems.
Gems works with nematode roundworms, and did an experiment in which he knocked out intracellular antioxidant proteins. He expected the creatures to die young, but instead to his surprise did not.
This experiment along with several others like it a are illustrated to propose the possibility that the free radical theory of aging is wrong after all and that antioxidant supplements may be harmful.
The article discusses the history of the theory, which readers here should be well familiar.
As we live and metabolize food and oxygen, the mitochondria generate reactive oxygen species, a type of free radical, similar to how cars produce tailpipe emissions as they burn gas.
The ROS then bounce around the cells damaging proteins, lipids, and DNA. The cumulative effect of this damage is aging.
Our cells have several powerful lines of intrinsic antioxidant molecules which neutralize the toxicity of ROS. So in the Gems experiment one would predict knocking out these molecules would increase aging. It did not.
His alternative theory of aging is relegated to a brief mention in the final paragraph:
“Gems, for one, believes the evidence points to a new theory in which aging stems from the overactivity of certain biological processes involved in growth and reproduction.”