Calorie restriction is the first and most compelling example of life extension in mammals.
Much speculation about how CR works has focused on ideas of what causes aging. Since
these causes themselves are much disputed, I have instead focused my thinking on lessons
from simple model organisms, which have emerged from recent genetic studies. These
findings can now be integrated with numerous, elegant studies on CR over the decades,
which provide a treasure trove of information about physiological changes that are elicited …