of the few proven ways to extend the maximum life span (as opposed
to the mean life span) of laboratory animals has been caloric restriction
(CR). CR has been shown to extend maximum life span of animals up
to 80%! Human research finds similar benefits of improved health
and vigor, but comparable life-span research in humans has not been
conducted. Those involved
in the Biosphere II experiment were an example of human CR research.
big question has been why does CR extend life span. A new study published
in the Proceedings of the National Academy of Sciences sheds
some light on this question. The study gives clues as to how CR
actually reverses aging. The hope would be to eventually find ways
to harness the biological effects of CR without having to eat less.
This new study may be an important step in that direction.
Life Extension Foundation has published an interview with a researcher
in the new study, Dr Stephen Spindler:
Aging Rapidly with Short-Term Calorie Restriction
Extension Foundation-funded Research Breakthrough Published in the
Proceedings of the National Academy of Sciences
Interview with Stephen R. Spindler, Ph.D.
Tuesday, Sep. 4th, the Proceedings of the National
Academy of Sciences (PNAS) web site features a paper from the
laboratory of Dr. Stephen Spindler, who has been probing the life-extending
effects of calorie restriction using advanced gene chip technology.
(For an explanation of gene chip studies of aging, please see
our interview with Drs. Tomas Prolla and Richard Weindruch in
the November, 1999 issue of Life Extension Magazine.) Dr.
Spindler examined aging changes in the expression of 11,000 genes
and the modification of these changes by calorie restriction.
The major conclusions from this study are that many of the life
extension effects of calorie restriction happen rapidly, and that
these effects can be shown not only in young animals, but also
in old animals not previously on calorie restriction. Calorie
restriction not only slows aging and extends maximum life span,
but it partially reverses aging changes as well! On top of that,
the fact that calorie restriction acts rapidly means that, for
the first time, it is possible to test anti-aging interventions
in weeks rather than years, which should drastically accelerate
the search for anti-aging treatments. Dr. Spindler, who is a professor
at the Department of Biochemistry at the University of California
at Riverside and works for a company called LifeSpan Genetics,
was interviewed about his results by Dr. Gregory M. Fahy and by
Life Extension Foundation founder and president Saul Kent on August
Extension: Dr. Spindler, what is the essence of your new observations,
which are just coming out in PNAS?
Spindler: I think the conclusion you can reach from the paper is
that even in very old animals, caloric restriction will very rapidly
produce most of the gene expression effects that you see in long-term
calorie-restricted animals. That means, I think, that even in the
short-term, older people may be able to benefit rapidly from switching
to a calorically-restricted diet, and that fits with some of the
information that has been in the literature for years. For instance,
type II diabetics improve when they start under-eating. Their blood
glucose levels improve. Their insulin sensitivity improves. Their
general health improves, even before the fat mass, for instance,
is depleted. So, there have been some hints that underfeeding could
produce positive effects rather rapidly, but this research that
we are publishing shows this for the first time, directly, using
gene expression profiles as biomarkers for the effects of caloric