What strategies actually work to fight dying?
A prominent biologist tackles a morbid topic
FOR most of human history, death has been a blunt fact of life. People died because they were eaten, had an accident or developed an infection. In 1950 global life expectancy was 46.5 years. But now that the world is richer and healthier, it is almost 72. Living longer exposes more people to the wear and tear of ageing. Unlike their ancestors, they spend little time dodging predators and worry instead about succumbing to dementia or simply to frailty.
In“Why We Die”, Dr Venki Ramakrishnan asks whether it is possible to arrest the decay of body and mind. A molecular biologist based in Britain, Dr Ramakrishnan won a Nobel prize in 2009 for his work on how cells generate the proteins that make up human bodies. As those cells accumulate chemical damage, for instance from toxins, they malfunction, and their inherent repair mechanisms deteriorate.
Though technical terms pepper his account, he has a jauntily accessible style. He likens a breakdown in vital proteins to an orchestra playing discordantly. When discussing how the energy-generating mitochondria in cells degrade over time, he pictures them “rusting from within”.
Is this decline inevitable? Dr Ramakrishnan notes that some species, such as jellyfish, respond to injury or stress by rejuvenating themselves. Among mammals, the naked mole rat stands out, seemingly resistant to heart disease and cancer. Can humans learn the secrets of longevity from the mole rat – or from the hydra, a tiny aquatic creature capable of indefinite self-renewal? Scientists are trying.
Quest to cheat death
The quest to cheat death has a long history. More than 2,000 years ago Qin Shi Huang, a Chinese emperor, directed a team of envoys to seek the elixir of life. He died at 49, apparently killed by the very potions he dreamed would preserve him.
Only in the past 50 years have biologists fully grasped the processes that cause ageing. Scientists harness ever more sophisticated tools to manipulate cells and genes, and a new industry has sprung up. Some 700 biotech firms currently focus on ageing and longevity. Though they have achieved few advances, hype runs riot.
Dr Ramakrishnan takes a hard look at voguish therapies. Not all of them draw criticism. He cites evidence for the benefits of limiting calorie intake, and cautiously reports the promise of rapamycin, a drug that produces the same effects without the need to restrict diet. But there are many “dubious” enterprises pushing “crackpot” ideas. He is especially critical of cryonics, a process that involves freezing people after death and defrosting them when cures for their ailments are found.
Also in the firing line are messianic figures who tout fantasies of eternal life. One, Aubrey de Grey, asserts that the first humans to live to 1,000 have already been born; he promotes what he calls “longevity escape velocity”, the idea that human beings can improve average life expectancy faster than they age and thus never die.
Prophets of immortality attract funding from plutocrats who treat life as yet another system that can be hacked. Bryan Johnson, a tech entrepreneur, has spent an estimated US$2 million a year on his anti-ageing regimen, which until recently included blood transfusions from his teenage son (he has said these produced “no benefits”). Those who share his interest in anti-ageing research include Elon Musk, Jeff Bezos and Mark Zuckerberg: “When they were young, they wanted to be rich, and now that they’re rich, they want to be young,” writes Dr Ramakrishnan.
A wide gap in life expectancy still exists between rich and poor. The new science and business of longevity threaten to increase it. Dr Ramakrishnan is uncomfortable about this. By 2050 there will be 2 billion people who are over 60, reckons the World Health Organisation. He predicts mounting problems: overpopulation, dwindling natural resources and fewer workers to support a growing cohort of pensioners.
In the end he offers conservative advice. If you aspire to a long, healthy life, you should sleep well, exercise and eat moderately, consuming mainly plants. For those who favour bolder interventions, he has a simple message: “Even if we conquer ageing, we will die of…wars, viral pandemics or environmental catastrophes.”
Boosting your lifespan may beguile the imagination but could rob your existence of meaning, because there is no urgency to make every day count. Perhaps, after all, life’s transience is the key to its beauty.
Why We Die, By Venki Ramakrishnan; William Morrow; 320 pages; US$32.50. Hodder Press; £25