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Leonard Hayflick

Publications and source records attributed to Leonard Hayflick.

12 recordsLinked to original sources
PubMed2005

Misdirection on the road to Shangri-La.

Will life expectancy in the United States rise or fall in this century? The implications of either scenario are far reaching. We contend that the rise of childhood obesity in the United States in the past three decades has been so dramatic that it will soon lead to higher than expected death rates at middle ages and a possible decline in life expectancy by midcentury. The most detrimental health and longevity effects will not be seen for decades--a phenomenon that cannot be detected by current methods used to forecast life expectancy or estimate the number of deaths currently attributable to obesity. This scenario contrasts sharply with the views of mathematical demographers who generate forecasts by relying on the assumption that the U.S. pattern of longevity will follow that of other longer lived nations and on the extrapolation of historical trends in life expectancy into the future.

Journal Article↗
PubMed2005

Misdirection on the road to Shangri-La.

Will life expectancy in the United States rise or fall in this century? The implications of either scenario are far reaching. We contend that the rise of childhood obesity in the United States in the past three decades has been so dramatic that it will soon lead to higher than expected death rates at middle ages and a possible decline in life expectancy by midcentury. The most detrimental health and longevity effects will not be seen for decades--a phenomenon that cannot be detected by current methods used to forecast life expectancy or estimate the number of deaths currently attributable to obesity. This scenario contrasts sharply with the views of mathematical demographers who generate forecasts by relying on the assumption that the U.S. pattern of longevity will follow that of other longer lived nations and on the extrapolation of historical trends in life expectancy into the future.

Adolescent↗
PubMed2005

A potential decline in life expectancy in the United States in the 21st century.

Forecasts of life expectancy are an important component of public policy that influence age-based entitlement programs such as Social Security and Medicare. Although the Social Security Administration recently raised its estimates of how long Americans are going to live in the 21st century, current trends in obesity in the United States suggest that these estimates may not be accurate. From our analysis of the effect of obesity on longevity, we conclude that the steady rise in life expectancy during the past two centuries may soon come to an end.

Aged↗
PubMed2004

"Anti-aging" is an oxymoron.

No intervention will slow, stop, or reverse the aging process in humans. Whether anti-aging medicine is, or is not, a legitimate science is completely dependent upon the definition of key terms that define the finitude of life: longevity determination, aging, and age-associated diseases. Only intervention in the latter by humans has been shown to affect life expectancy. When it becomes possible to slow, stop, or reverse the aging process in the simpler molecules that compose inanimate objects, such as machines, then that prospect may become tenable for the complex molecules that compose life forms. Most of the resources available under the rubric "aging research" are not used for that purpose at all, thus making the likelihood of intervention in the process even more remote. If age changes are the greatest risk factor for age-associated diseases (an almost universal belief), then why is the study of aging virtually neglected?

Aged↗
PubMed2002

Position statement on human aging.

A large number of products are currently being sold by antiaging entrepreneurs who claim that it is now possible to slow, stop, or reverse human aging. The business of what has become known as antiaging medicine has grown in recent years in the United States and abroad into a multimillion-dollar industry. The products being sold have no scientifically demonstrated efficacy, in some cases they may be harmful, and those selling them often misrepresent the science upon which they are based. In the position statement that follows, 52 researchers in the field of aging have collaborated to inform the public of the distinction between the pseudoscientific antiaging industry, and the genuine science of aging that has progressed rapidly in recent years.

Aged↗
PubMedDate not supplied

Living forever and dying in the attempt.

Since the first cell culture was set at the beginning of the twentieth century it was believed that all cultured cells, if provided with the proper conditions, would replicate indefinitely. Sixty years later we overthrew this dogma by finding that normal cells have a finite capacity to replicate and that only abnormal or cancer cell populations can replicate indefinitely. We interpreted these findings to bear on our understanding of the aging process. If, as had been previously thought, normal cells can replicate indefinitely, then age changes could not have an intracellular origin. Our findings demonstrated that, on the contrary, age changes do have an intracellular origin. The hundreds of changes that were subsequently found to precede the loss of replicative capacity have been interpreted to be age changes and the finitude of replication to be an expression of longevity determination. Subsequent findings by others have determined the molecular mechanism that governs the finitude of normal cell replicative capacity and how immortal cancer cells escape this inevitability. Thus, key events in our understanding of aging, longevity determination and cancer have been revealed.

Aging↗