From Ouroboros: "A counter-intuitive proposal for a mechanism of lifespan extension comes from Schulz et al., who contend that glucose restriction extends worm lifespan by increasing mitochondrial respiration and thereby the production of reactive oxygen species (ROS). Wait, you thought that ROS were deleterious? Welcome to the topsy-turvy world of hormesis, the biological equivalent of Was mich nicht umbringt, macht mich starker, in which a little bit of a bad thing is actually a very good thing. ... Usually, however, hormesis comes from acute exposure to stress: even if it's repeated, there's a chance for the cells (or the body) to recover before the next challenge. What I'm having a tough time wrapping my head around is how a chronic stress (i.e., elevated ROS levels resulting from lifelong glucose deprivation) could protect the body from another chronic stress that is essentially identical (i.e., elevated ROS levels pursuant to aging). For the model to hold true, it seems that either the system must be exquisitely tuned and the authors were lucky to hit a very narrow 'sweet spot', or ROS production must be increasing resistance to other stresses that are more relevant to C. elegans lifespan than oxidation."