X-Message-Number: 24318 Date: Fri, 2 Jul 2004 20:39:03 -0700 (PDT) From: Doug Skrecky <> Subject: aging: the reality J Gerontol A Biol Sci Med Sci. 2004 Jun;59(6):B579-86. Aging: the reality: demography of human supercentenarians. An international committee of demographers has created a carefully documented list of worldwide living supercentenarians (>/=110 years old) that has been published by the Los Angeles Gerontology Research Group on its web site and updated on a weekly basis for the past 6 years [see "snapshot" for the year 2003 in the Appendix]. What can be learned by studying this distinguished group of individuals? Also, what are the implications for understanding the fundamental biological limits to human longevity and maximum life span? Our conclusion: Although everyone agrees that average life expectancy has systematically advanced linearly over the last century, it is not realistic to expect that this pace can continue indefinitely. Our data suggest that, without the invention of some new unknown form of medical breakthrough, the Guinness Book of World Records benchmark established by French woman Jeanne Calment of 122 years, set back in 1997, will be exceedingly difficult to break in our lifetime. J Gerontol A Biol Sci Med Sci. 2004 Jun;59(6):B573-8. Aging: the reality: "anti-aging" is an oxymoron. Hayflick L. 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? FASEB J. 2003 Apr;17(6):690-2. Epub 2003 Feb 05 Genotype and age influence the effect of caloric intake on mortality in mice. Long-term caloric restriction (CR) has been repeatedly shown to increase life span and delay the onset of age-associated pathologies in laboratory mice and rats. The purpose of the current study was to determine whether the CR-associated increase in life span occurs in all strains of mice or only in some genotypes and whether the effects of CR and ad libitum (AL) feeding on mortality accrue gradually or are rapidly inducible and reversible. In one experiment, groups of male C57BL/6, DBA/2, and B6D2F1 mice were fed AL or CR (60% of AL) diets beginning at 4 months of age until death. In the companion study, separate groups of mice were maintained chronically on AL or CR regimens until 7, 17, or 22-24 months of age, after which, half of each AL and CR group was switched to the opposite regimen for 11 wk. This procedure yielded four experimental groups for each genotype, namely AL-->AL, AL-->CR, CR-->CR, and CR-->AL, designated according to long-term and short-term caloric regimen, respectively. Long-term CR resulted in increased median and maximum life span in C57BL/6 and B6D2F1 mice but failed to affect either parameter in the DBA/2 mice. The shift from AL-->CR increased mortality in 17- and 24-month-old mice, whereas the shift from CR-->AL did not significantly affect mortality of any age group. Such increased risk of mortality following implementation of CR at older ages was evident in all three strains but was most dramatic in DBA/2 mice. Results of this study indicate that CR does not have beneficial effects in all strains of mice, and it increases rather than decreases mortality if initiated in advanced age. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=24318