Is our lifespan fixed, or could we slow down or even abolish ageing?
As much of the world gets older, the question of whether our lifespan is fixed, or could we slow down or even abolish ageing, has prompted an explosion of research. Photo / Getty Images
‘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.