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.