One for the Record Book

Here’s a curious coincidence: The current world records for human longevity and for running the mile were both set back in the 20th century. The longest-lived human was France’s Jeanne Calment, who reached 122 years and 164 days of age before her death in 1997. In 1999, Morocco’s Hicham El Guerrouj ran the world’s fastest mile to date in just over three minutes and 43 seconds.

The fact that these records have stood for over a decade is more than a little surprising. During the 20th century there were continual improvements in longevity and mile-running times. In the late 1990s it seemed the gains would continue apace—there were obviously limits to what the human body could do without bionically rebuilding it, but they didn’t appear to be in sight. Now things look different.

Not only is Jeanne Calment’s life-span record unbroken, no one has come close to it since she passed on. While four “supercentenarians” reached at least 117 during the 1990s, no one has lived that long since 2000. (The second longest-lived person on record is Shigechiyo Izumi, who reportedly died in 1986 at age 120 and 237 days—there are doubts about his age at death, though.) Meanwhile, gains in life expectancy, or average life-span, appear to be flattening out—U.S. life expectancy rose by about 2% during each of the 1980s and 1990s, but over the past decade it has risen by about 1.6%.

As for running, you have to go back more than a century to find another era in which the world record for the mile stood for more than a decade. And some distance-running records have existed even longer than El Guerrouj’s. The high-school record for the mile (in a race including only high-schoolers) has stood for nearly a half century—it was set in 1965 by Kansan Jim Ryun, who won the Kansas High School State Meet that year with a time of 3:58.3. The collegiate records for the three-mile and the six-mile were set in the early 1970s by Steve Prefontaine, the storied University of Oregon runner who was tragically killed at age 24 in a 1975 car accident.

This isn’t to say we’re approaching hard and fast limits when it comes to longevity and running. But the marked slowing of gains in both realms of physical endeavor underscores a hard truth: We’ve gotten so many contributing factors right when it comes to longevity (reduced death from infectious diseases, better diets, improved geriatric care) and running (better conditioning routines, lighter shoes, faster track surfaces) that it seems we’ve nearly run out of ones that are crying out for improvement. To put it another way, making further substantial gains will require the simultaneous optimization of ever more factors that are already nearly optimal. (Such factors, by the way, include the extraordinary good luck of people who possess rare combinations of genes that abet extreme longevity or world-class running speed.) The killer issue is simultaneity—improving just one contributing factor may not be all that hard, but getting many of them more right than ever before is really, really tough.

When it comes to pushing the envelope on healthy life span, getting everything more right than ever means simultaneously lowering the risk of death from many hard-to-treat diseases of aging. That is, in the developed world we’ve already mostly eliminated early-life mortality risks, such as diphtheria and measles, and we’ve greatly cut mid-life ones too, such as fatal heart attacks before age 60, with preventatives such as hypertension drugs. In order to further boost life expectancy, we must now find a way to substantially lower the risk of death after age 75 from Alzheimer’s disease, all forms of cancer, Parkinson’s, heart failure, stroke, and many other killer diseases whose risk is not only quite high for people at such advanced ages, but also soaring even higher as they grow older. (And I’m focusing on life expectancy here because I think it’s a good proxy for what matters most: average health-span—no one wants to live an extra-long time in miserable health. Besides, rising life expectancy is tightly tied to the setting of longevity records, since it increases the number of extremely long-lived people who have a shot at setting a new record.)

A revealing 1990 study highlighted the daunting magnitude of this challenge. It showed that if we could totally wipe out cancer, U.S. life expectancy would rise by only about 3.2 years. (Based on 1985 actuarial data.) Eliminating all deaths from ischemic heart disease (the kind caused by clogged arteries) would yield a similarly small increase in life expectancy. The reason these gains would be surprisingly small is that numerous diseases are competing to kill us after 75, so even if we eliminated one of them, something else would soon get us and thus prevent life expectancy from rising very much. You can see from these startling figures that our current strategy of treating tough diseases of aging one at a time, often when it’s late and little can be done, isn’t likely buy us much in the way of quality time. And it’s obviously very difficult and expensive to attain even the relatively minor gains in average health- and life-span that we’re managing to eke out these days via the conventional, one-disease-at-a-time approach.

All this makes a compelling case for investing more of our medical-research dollars in anti-aging R & D. If we could slow aging in humans as much as we’ve already been able to in mice with an existing drug, we could increase average life-span at birth by about nine years. Do the math: This means developing drugs that modestly slow aging (which leading gerontologists say is now realistically achievable) would be like totally winning the war on cancer three times over. No other medical advance on the horizon promises such large gains in healthy life as anti-aging drugs do, because nothing else would so effectively deal with the killer issue of simultaneity mentioned earlier—almost by definition, decelerating the aging process would push off all fatal diseases of aging at the same time, as well as cut the age-associated risk of nonfatal ills, such as hearing loss and bone-thinning, that lower our quality of life as we get older. As a fringe benefit, anti-aging drugs would probably lead to a lot of new world records—including ones by middle-aged runners, for whom medicines that retard the loss of youthful speed and endurance, along with everything else that goes downhill as we age, would be the ultimate safe, performance-enhancement drugs.

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