Editor's Note: We are reposting this essay from our June 2002 issue to accompany our coverage of The Curious Case of Benjamin Button. To read the full position statement on aging and its extensive list of references, follow this link.
Efforts to combat aging and extend human life date at least as far back as 3500 B.C., and self-proclaimed experts have touted anti-aging elixirs ever since. Indeed, the prospect of immortality has always had universal appeal, spurring Alexander the Great and Ponce de León to search for the legendary Fountain of Youth and feeding alchemists’ desire to manufacture gold (once believed to be the most potent anti-aging substance in existence). But the hawking of anti-aging “therapies” has taken a particularly troubling turn of late. Disturbingly large numbers of entrepreneurs are luring gullible and frequently desperate customers of all ages to “longevity” clinics, claiming a scientific basis for the anti-aging products they recommend and, often, sell. At the same time, the Internet has enabled those who seek lucre from supposed anti-aging products to reach new consumers with ease.
Alarmed by these trends, scientists who study aging, including the three of us, have issued a position statement containing this warning: no currently marketed intervention—none—has yet been proved to slow, stop or reverse human aging, and some can be downright dangerous. While the public is bombarded by hype and lies, many biologists are intensively studying the underlying nature of aging in the belief that their research will eventually suggest ways to slow its progression and to thereby postpone infirmity and improve quality of life. But anyone purporting to offer an anti-aging product today is either mistaken or lying. (Here's the full position statement.) Here we state the case as we see it, speaking for ourselves.
What Aging Is... and Isn’t Any discussion of aging should first clarify its terms. Various definitions have been proposed, but we think of aging as the accumulation of random damage to the building blocks of life—especially to DNA, certain proteins, carbohydrates and lipids (fats)—that begins early in life and eventually exceeds the body’s self-repair capabilities. This damage gradually impairs the functioning of cells, tissues, organs and organ systems, thereby increasing vulnerability to disease and giving rise to the characteristic manifestations of aging, such as a loss of muscle and bone mass, a decline in reaction time, compromised hearing and vision, and re-
duced elasticity of the skin.
This accretion of molecular damage comes from many sources, including, ironically, the life-sustaining processes involved in converting the food we eat into usable energy. As the energy generators of cells (mitochondria) operate, they emit destructive, oxidizing molecules known as free radicals. Most of the damage caused by these reactive molecules gets repaired, but not all. Biologists suspect that the oxidative assaults ultimately cause irreparable injury to the mitochondria, thereby impeding the cell’s ability to maintain the integrity of the countless molecules needed to keep the body operating properly. The free radicals may also disrupt other parts of cells directly.
Aging, in our view, makes us ever more susceptible to such ills as heart disease, Alzheimer’s disease, stroke and cancer, but these age-related conditions are superimposed on aging, not equivalent to it. Therefore, even if science could eliminate today’s leading killers of older individuals, aging would continue to occur, ensuring that different maladies would take their place. In addition, it would guarantee that one crucial body component or another—say, the cardiovascular system—would eventually experience a catastrophic failure. It is an inescapable biological reality that once the engine of life switches on, the body inevitably sows the seeds of its own destruction.