‘Who wants to live forever?” we bravely tell ourselves. But if we were offered a pill that promised another 10 or 20 years of life, how many of us would really say no?
For better or worse, that’s not a decision you’re likely to face soon. Nobel Prize-winning biologist Venki Ramakrishnan has surveyed the many and varied efforts to extend the human lifespan and – to jump to his conclusion – decided it will be another decade or two before we know whether current anti-ageing research is likely to deliver results.
Over the past 150 years, average life expectancy has already doubled, thanks largely to reduced infant mortality. “But extending maximum lifespan – the longest we can expect to live even in the best of circumstances – is a much tougher problem,” argues Ramakrishnan. “Is our lifespan fixed, or could we slow down or even abolish ageing as we learn more about our own biology?”
As much of the world gets older, that question has prompted an explosion of research. Every year, scientists publish tens of thousands of papers on ageing and hundreds of new companies have invested billions of dollars in efforts to lengthen lifetimes.
But for all that research, scientists still don’t know whether humans have an absolute maximum lifespan. Maybe there really is a limit. After all, even before Covid, life expectancy wasn’t increasing as quickly as it once did. Yes, there are more and more 100-plus-year-olds, but it’s been almost 27 years since France’s Jeanne Calment died at the age of 122, and no one has yet beaten her record.
On the other hand, a few animals live much longer than we do – some whales live to more than 200 years old, Greenland sharks to maybe 400, so who knows?
Much of this book is about describing various mechanisms that appear to control the ageing process, and efforts to tweak them. That means taking a deep dive into DNA, mutation, the way the genetic code repairs itself (or doesn’t) and the control systems that tell our cells when to grow and when to take a break.
It’s popular science writing but it helps to have a healthy appetite for the intricacies of cell biology, protein folding, epigenetics, mitochondrial dysfunction and other arcana.
The researchers don’t have it easy. If there’s one thing we do know by now, it’s that ageing isn’t a simple cause-and-effect business, often involving multiple systems operating together in subtle ways. As well, humans don’t make great research subjects when you’re probing such a long-term phenomenon, so a lot of work has to be done on more tractable organisms: mice, nematodes, even yeast.w
This is serious science, but there’s crazy stuff, too. Cryonics, or body freezing, has been out there on the fringe for decades, and if you’re so inclined and have enough money, there are commercial services that will drain the blood from your corpse, replace it with antifreeze and store your remains, theoretically indefinitely, in liquid nitrogen. Or maybe just your brain. All despite zero evidence that a preserved body could ever be reanimated, or that information could be extracted from deep-frozen grey matter.
Or, if your pockets are really deep, you could copy US tech mogul Bryan Johnson, who spends US$2 million a year on an anti-ageing regime that includes “two dozen supplements, a strict vegan diet and … more than 33,000 images of his bowels”.
Even away from the fringes, many anti-ageing therapies remain unproven at best. Remember resveratrol? At one time, the compound found in red wine appeared to come with the perfect sales pitch: quaff your way to better health and a long life. Sadly for wine-lovers, Ramakrishnan says mainstream scientists long ago discounted resveratrol as a way of increasing lifespan.
What about fasting, or otherwise severely limiting how much we eat? “Caloric restriction”, the scientists call it, and it does appear to be effective against cancer and diabetes, while reducing mortality, but has some major downsides – constant hunger being the most obvious. However, serious research is being put into drugs that mimic the beneficial effects of caloric restriction without the drawbacks; Ramakrishnan doesn’t name them but we know them through brand names such as Ozempic and Wegovy.
It’s the same message for some other potentially life-extending therapies: more research needed.
But maybe the researchers are aiming at the wrong target. Instead of adding extra years, perhaps the goal should be making the final years as healthy as possible. Inevitably, there’s a technical term for that, too: “compression of morbidity”, or as one researcher has put it, living long and dying young.
After all, if we succeed in living much longer without also compressing morbidity, all we will have achieved is more years of sickness, while adding to the social cost of caring for the elderly.
While we wait for the scientists, Ramakrishnan has some big questions. If we do unlock the secret to a much longer life, who’ll get treated? Anyone who wants a few more years, or only those who can pay? Will it just add to the existing inequality in life expectancy? (If you want to live to a ripe old age, being relatively wealthy is an excellent first step.) And if you want to go on for another 10 or 20 years, do you also want to keep working past 75 or 85?
And in the end, what’s the point? We’re living twice as long as we did a century ago and we’re still not happy. “If we live to be 120 or 150 years old, we will fret about why we can’t live to 300 … It may be simpler to accept that our life is limited.”
In the meantime, anti-ageing studies are at least proving that for now, the old advice is the best advice: eat well, and not too much, get some exercise and plenty of sleep.
As Ramakrishnan writes, “These remedies currently work better than any anti-ageing medicine on the market, cost nothing and have no side effects.”
Why we die: The new science of ageing and the quest for immortality by Venki Ramakrishnan (William Morrow, $39.99) is out now.
