Are we really doomed to grow old and die?

True: Ageing is responsible for more than 100,000 deaths every day

Of the 150,000 deaths that occur on Earth every day, over two thirds of them are due to age­ing¹. This is because, bio­lo­gic­ally, the age­ing pro­cess is the cause of our biggest killers, like can­cer, heart dis­ease and demen­tia². Though diet, life­style and oth­er factors can make these more or less likely, their effect is dwarfed by the bio­lo­gic­al con­sequences of get­ting older: hav­ing high blood pres­sure can double your risk of a heart attack, but being 80 rather than 40 mul­ti­plies it by ten ³. As a res­ult, age­ing is the single largest cause of death and suf­fer­ing, globally.

False: The ageing process is inevitable

Though we think of get­ting older as a nat­ur­al fact of life, this isn’t the case for all spe­cies. Bio­lo­gists have a simple defin­i­tion of age­ing: an increase in risk of death with time. Humans have a risk of death that doubles every eight years⁴. How­ever, some spe­cies, includ­ing some tor­toises, fish and sala­man­ders, are ‘neg­li­gibly senescent’—more plainly, they don’t age⁵. Along with their unchan­ging risk of death, these anim­als don’t become frail or less fer­tile with time. This means that their ‘health­span’ is increased, along with their lifespan.

Uncertain: How long we can hope to live

Every so often, a study pro­poses a ‘lim­it’ on human lifespan, either by look­ing at demo­graph­ic trends, or ana­lys­ing aspects of human bio­logy. How­ever, these ‘lim­its’ have repeatedly been smashed his­tor­ic­ally, as life expect­ancy in the lead­ing coun­try has increased by three months per year, every year for almost two cen­tur­ies⁶. Are we approach­ing a real bio­lo­gic­al lim­it now? Or can medi­cines that tar­get the age­ing pro­cess help us sidestep the con­straints that evol­u­tion has placed on us, and help humans become more like neg­li­gibly sen­es­cent tortoises?

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True: We can slow down and even reverse the ageing process in the lab

Sci­ent­ists have found dozens of ways to inter­vene in the age­ing pro­cess in the lab. The first indic­a­tion came in the 1930s, when sci­ent­ists study­ing diet in rats noticed that those eat­ing less lived sub­stan­tially longer than their peers allowed to eat what they liked—and they did so in good health, stay­ing fit and with less dis­ease⁷. We’ve since rep­lic­ated this feat by find­ing genes that can slow age­ing, and using drugs and oth­er treat­ments that alter aspects of the age­ing pro­cess, slow­ing the decline in lab anim­als. The first of these are already being tri­alled in humans.

False: Living longer would mean extra years in a nursing home

A lot of people ima­gine that liv­ing longer would mean extend­ing the frail years at the end of life, drag­ging out our decrep­itude. But this under­stand­able worry gets things back­wards from a bio­lo­gic­al per­spect­ive: as we treat age­ing, we’d increase health­span by defer­ring the age-related changes that cause dis­ease, and this would cause people would live longer, rather than the oth­er way around. This makes sense in theory—because you have to die of some­thing, so not being ill means you’re much less likely to die—and also in prac­tice, where both slow-age­ing lab anim­als and excep­tion­ally long-lived humans don’t just live longer, but spend a great­er frac­tion of their lives in good health.

Uncertain: How medical practice and regulation will adapt to these new, preventative treatments

The dream of real anti-age­ing medi­cine is pre­vent­at­ive treat­ments that would slow down our decline as we age, and pre­vent many or even all of the age-related killers. How­ever, this approach is very dif­fer­ent to cur­rent medi­cine, which usu­ally waits for dis­eases to arise before inter­ven­ing, and then treats them indi­vidu­ally. This means that reg­u­lat­ors, like the FDA in the US or EMA in Europe won’t approve a drug unless it’s effect­ive against a spe­cif­ic dis­ease. We need a soci­et­al debate about how we should go about approv­ing pre­vent­at­ive treat­ments for ageing—and the poten­tial bene­fits are so large it’s crit­ic­ally import­ant that we get this right.

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True: Billionaires and private companies are trying to slow the ageing process

In 2013, Google launched a spin-out called Calico aim­ing to under­stand and inter­vene in the age­ing pro­cess. This year, Amazon founder Jeff Bezos sunk some of his bil­lions into a com­pany called Altos Labs, work­ing on an age-revers­ing tech­no­logy called ‘cel­lu­lar repro­gram­ming’. After dec­ades as a niche sci­entif­ic pur­suit, age­ing bio­logy finally has enough con­crete res­ults that big investors are get­ting inter­ested. How­ever, there’s still lots of work to do, includ­ing fun­da­ment­al bio­logy typ­ic­ally stud­ied in uni­ver­sit­ies and research insti­tutes, and more fund­ing is des­per­ately needed: in the US, only about a dol­lar of gov­ern­ment fund­ing per Amer­ic­an is spe­cific­ally ear­marked for research to under­stand the age­ing process—compared to more than $10,000 per per­son spent on health­care, a num­ber which age­ing research could sub­stan­tially reduce⁸.

False: We’re on the brink of immortality!

The press loves to run with head­lines about liv­ing forever, par­tic­u­larly in the con­text of bil­lion­aires invest­ing in age­ing research to give them a bit longer to spend their unima­gin­able wealth. How­ever, immor­tal­ity isn’t on the cards even in the best-case scen­ario: even neg­li­gibly sen­es­cent anim­als still die (the old­est recor­ded Galápa­gos tor­toise, Har­riet, died of a heart attack—the dif­fer­ence between her and a human was that she lived 175 healthy years first!)⁹.  Even if the out­come isn’t immor­tal­ity, it could still be hugely sig­ni­fic­ant: a recent paper estim­ated that delay­ing age­ing by just one year would be worth $37 tril­lion to the US eco­nomy alone, and lar­ger gains would be worth pro­por­tion­ately more¹⁰.

Uncertain: When these medicines might arrive

In spite of big-money bets from bil­lion­aires, it’s not clear how long it will be before we can expect to see the first anti-age­ing medi­cines in hos­pit­als, or the loc­al phar­macy. Mov­ing from an idea that works in mice in the lab to human treat­ments is a notori­ously dif­fi­cult pro­cess. How­ever, it seems likely that they will arrive in time for most people alive today. Some pro­posed treat­ments are drugs that we already use for spe­cif­ic con­di­tions, such as dia­betes drug met­form­in and, if that works against age­ing, there’s no reas­on we couldn’t roll it out glob­ally with imme­di­ate effect (it helps that it’s a well-under­stood medi­cine that costs cents per pill). Oth­er front-run­ners, like ‘senolyt­ic’ drugs that remove aged, sen­es­cent cells from the body have proved their mettle in mice and are already under­go­ing human tri­als, so it’s quite pos­sible they could be in use before the dec­ade is out. More spec­u­lat­ive ideas, like the cel­lu­lar repro­gram­ming being explored by Altos Labs, might be dec­ades away—but, if you’re middle-aged or young­er today, or a little older but live longer thanks to the first gen­er­a­tion of anti-age­ing drugs, a few dec­ades is still soon enough to mat­ter. This means, while we can’t be sure, I think it’s well worth get­ting excited about age­ing biology—and doing more research to make unlock­ing the enorm­ous poten­tial eco­nom­ic, social and health gains more likely.