Why do we age? Is aging inevitable? Will advances in medical knowledge allow us to extend the human lifespan beyond its present limits? Because growing old has become the one irreducible reality of human existence, these intriguing questions arise more often in the context of science fiction than science fact. But recent discoveries in the fields of cell biology and molecular genetics are seriously challenging the assumption that human lifespans are beyond our control.

With such discoveries in mind, noted cell biologist William R. Clark clearly and skillfully describes how senescence begins at the level of individual cells and how cellular senescence is bound up with aging of the entire organism. He explores the evolutionary origins of aging, the cellular connections between aging and cancer, the parallels between cellular senescence and Alzheimer's disease, and the insights gained through studying human genetic disorders - such as Werner's syndrome - that mimic the symptoms of aging. Clark also explains how reduction in caloric intake may actually help increase lifespan, and how the destructive effects of oxidative elements in the body may be limited by the consumption of anyioxidants found in fruits and vegetables. In a final chapter, Clark considers the social and economic consequences of living longer, the implications of gene therapy on senescence, and what we might learn about aging from cloning.

This is a highly readable, provocative account of some of the most far reaching and controversial questions we are likely to ask in the next century.

"If we want to understand why we age or if we can slow down the aging process, we first have to understand why we age. A Means to an End, written by Dr, Clark, is a very readable book about the biological basis of aging."

- Jerry W. Shay, Professor
University of Texas Southwestern Medical Center at Dallas

"…Why in spite of healthy, well-fed, well-watered lives do people age and die? The well-informed scientist-researcher William R. Clark excitedly reveals new studies…as he tracks the inevitable corrolary to human life: the inexorable, rhythmiv march to human death."

- Lynn Margulis, Distinguished University Professor
University of Massachussetts, Amherst