Decelerating and Arresting Human Aging

Aging is the bane of our human existence. It is responsible for degenerative diseases of the body and mind and is the cause of much pain, suffering, and diminished quality of life. It is a constant reminder of our mortality. Assuming that mortality is not a disease, and that aging is an intrinsic property of mortality, aging itself is not a disease. But the degenerative features of many diseases are the by-product of aging. Thus it would seem intuitively desirable to intervene in and decelerate or arrest this process. If this intervention were successful, then it could slow the development of and perhaps even prevent diseases and thereby extend the human lifespan. Decelerated and arrested aging could greatly improve the quality of life and increase the well-being of many people.

In this chapter, I explore medical, social, and psychological dimensions of these two types of intervention aimed at altering aging. Regenerative medicine may be a mixed blessing. In many cases, it could result in a modest increase in the lifespan. But it could also entail a trade-off between increased quantity and quality of life in terms of physical function and decreased quality of life in terms of cognitive function. This could cancel out any early benefits of the intervention. A similar trade-off could occur to a greater degree if genetic manipulation of aging mechanisms substantially extended the lifespan. Whether this would benefit us would depend on whether we could retain equal physical and cognitive functioning through the extended period of our lives. In addition, tinkering with genes to decelerate or arrest aging might unleash growth factors normally suppressed by these same genes and result in diseases such as cancer. Even a modest increase in the lifespan for the elderly could be unfair to the young by burdening them in different ways. At a deeper level, such an increase could alter the natural contour of a human life and its component stages. Much of the discussion in this chapter is speculative, especially with respect to the second type of intervention I have described. Nevertheless, given our understanding of the biology of aging and the theoretical possibility of extending the human lifespan, speculation can be the catalyst for consideration of issues raised by intervention in the aging process.