Once Aging Is Curable, How Long Will We Live?

by Patrick Cox
October 1, 2018

In the past week, I talked to two unconnected researchers whose teams believe they have discovered the genetic mechanisms that control aging. More importantly, both believe that they know how to reverse those mechanisms to restore peak adult health.

If they’re right, the impact will be unprecedented—so it may be wise to begin pondering the possibility of age reversal now.

It’s probably inevitable that the ability to permanently restore animals, including humans, to the point of peak adult health will lead to the use of the word “immortal.” It is, in fact, the biological term for cells that don’t age.

You already have immortal cells in your body. They are the germline, the ova or sperm involved in sexual reproduction. Embryonic stem cells are also immortal.

Another form of immortal cell is induced pluripotent stem (iPS) cells, which are very similar to embryonic cells. I’ve had skin cells from my right arm genetically engineered into iPS cells. Cared for properly, they will live and replicate forever without aging.

Nevertheless, people who are permanently restored to peak adult health will not be immortal. Yes, regenerative medicine will reverse aging and extend healthspans dramatically—but it won’t grant us divinity or superpowers. Something will eventually kill everybody.

 

There’s No Shortage of Things That Could Kill You

If you travel by air, you are susceptible to the risks of aircraft failure, pilot error, and freak weather events. The odds of death are higher if you’re in a car per mile traveled. Motorcycles and bicycles entail even greater danger.

Living in South Florida, I often risk electrocution by taking a shower. If you hold a metal golf club over your head in an open expanse of grassland, you are at risk—even on a sunny day—from storms many miles away. Boaters increase their odds of being killed by lightning every time they go out on the water. Sailboats with tall masts are particularly effective lightning magnets.

Even if you showered in a Faraday cage and never left your safety bunker, you could join the 5,000 Americans who die of food poisoning every year. If you eat alone, the risk of death by choking goes up.

If you’re ever around bugs, birds, rodents, cats, dogs, or other animals, you are at risk because the pathogens they carry occasionally mutate into lethal diseases. If you live in a region subject to earthquakes, tornadoes, blizzards, hurricanes, floods, or sinkholes, you are subject to potentially lethal dangers.

You get the point. There is no way to completely protect yourself from “freak accidents.” The ancient Greek playwright Aeschylus was killed by a turtle dropped by an eagle. I might have doubted the story, but I used to live next to a tree with nesting eagles that regularly dropped large fish on my roof and yard.

The risk of being killed by something other than aging is relatively low over the average lifespan of about 80 years, even factoring in traffic accidents, homicide, and suicide. However, it’s a mathematical truism that the probability of dying from something other than an age-related disease will go up over longer lifespans.

Actuarial scientists can estimate how long people would live on average if old age were taken out of the picture.

So let’s play a game…

 

Guess How Long the Average Non-Aging Human Would Live?

To inform your decision and separate the answer from the question, here a few charts from the CDC on causes of US mortality by age group. The first includes all causes of death, highlighting nonmedical causes. The second ranks all injury deaths and highlights accidental deaths.

The answer, according to some actuarial scientists, is that life expectancy in a developed society without old-age-related deaths would be 600–700 years. That assumes, of course, that people in the future won’t be subject to significantly more or fewer risks. Either is possible.

Clearly, a 650-year healthspan is a lot longer—and I’d argue better—than the current 80-year life expectancy. It’s also a very long way from true immortality. Some people, due to bad luck, wouldn’t live past current normal lifespans. Others would live longer than average.

Curiously, the lifespans attributed to the Biblical patriarchs, including Methuselah, are pretty close to the sort of mortality distribution we could expect to see in non-aging populations. I’m telling you this only because it’s interesting, not because I’m making a religious point.

It does, however, make the title of my book, The Methuselah Effect, more meaningful. I didn’t actually come up with the title; that credit goes to my editor Shannara. We’re currently revising the book to include dramatic new discoveries that have emerged in the last year or two.

 

We’re on the Threshold of Something Big

Regarding the two researchers I referenced earlier: I don’t know everything about their discoveries and can’t tell you some things that I do know. These scientists will obviously keep many important details secret until they’ve filed patents and published the results of their trials. What I do know, though, is that they are looking at very similar components of cellular and genetic biology.

In the past, the process of aging was explained using vague hand-waving theories about the body just wearing out due to accumulated damage. I predict we’ll see a new consensus on aging emerge in the next few years.

The new view will be that aging is caused by specific molecular and genetic mechanisms that fully kick in sometime after childhood. Therefore, interventions will not only halt aging but reverse it by restoring regenerative mechanisms normally seen only in embryonic cells.

The attitudes and beliefs of scientists change long before they trickle down to the public, but I expect we’ll see evidence of this profound paradigm shift in peer-reviewed journals within two to three years.

 

— Once Aging Is Curable, How Long Will We Live? originally appeared at Mauldin Economics.