A new hypothesis on aging via the Juvenon Health Journal: "In general, species with higher metabolic rates have the shortest life spans. Demetrius's hypothesis holds that it is not the stresses of life, such as oxidative stress produced by free radicals, or the relative metabolic rates, that are important in determining life span. He believes the more important issue is metabolic stability, which is defined as the capacity of the networks of cellular metabolic pathways to continue to run smoothly, even during times of stress. ... One established method to increase life span in the mouse is caloric restriction (CR). Of interest, and in support of this theory, is experimental evidence showing that caloric restriction does in fact tend to stabilize metabolic pathways." This leads to the conjecture that CR will not do much for human maximum longevity, even though it is demonstrably effective at lowering risk for age-related conditions, as a healthy human already has a much more stable metabolism than mice.