The social consequences of extending the human life span might be quite bad; perhaps the worst outcome is that power could be concentrated into ever fewer hands, as those who wield it gave way more slowly to death and disease. But the worry that more life would damage individuals' quality of life is not persuasive. Depending on what the science of aging makes possible, and on how people plan their lives, longer life might even facilitate a richer and deeper life.

New C. elegans studies imply that lipases and lipid desaturases can mediate signaling effects on aging. But why might fat homeostasis be critical to aging? Could problems with fat handling compromise health in nematodes as they do in mammals? The study of signaling pathways that control longevity could provide the key to one of the great unsolved mysteries of biology: the mechanism of aging. But as our view of the regulatory pathways that control aging grows ever clearer, the nature of (...) aging itself has, if anything, grown more obscure. In particular, focused investigations of the oxidative damage theory have raised questions about an old assumption: that a fundamental cause of aging is accumulation of molecular damage. Could fat dyshomeostasis instead be critical? (shrink)