In the words of Taylor Swift, I might be “feeling 22” but the reality is that my 39th birthday approaches and with that the slow creep to 40: official midlife territory. The desire to stay young feels like a universal pursuit, whether you are Swift, Madonna or Jeff Bezos. Indeed, it is an obsession that transcends the centuries: in 1513, explorer Juan Ponce de León discovered Florida while searching for the fountain of youth and eternal life.
Fast forward just more than 500 years and American tech centimillionaire Bryan Johnson is on his own voyage of discovery. Johnson reportedly spends $2m (£1.6m) a year on an intensive regime designed to reduce his biological age from 45 to 18. He recently made headlines for injecting himself with his 17-year-old son’s plasma, after studies in mice showed young blood can rejuvenate old tissue.
In these experiments, two mice (one old and one young) were stitched together to share a circulatory system. Within five weeks, the blood from the younger mouse had restored muscle and liver cells – and enhanced growth of brain cells – in the older one. On the other hand, the young mice who were exposed to older blood had reduced growth. The experiments were not without risk. In a 1956 study that joined 69 pairs of rats, scientists noted that if two rats were not adjusted to each other, one would chew the head of the other until it was destroyed. In addition, 11 pairs died within one to two weeks of conjoining, probably due to tissue rejection.
So why would a multimillionaire want to be infused with his son’s blood based on such a rudimentary experiment? Johnson’s quest is indicative of our singular obsession as a society with looking younger and living longer in the face of an ever-elusive anti-ageing “cure”. Demand for anti-ageing elixirs is huge, from widely available skin and hair products, to surgical procedures and less common medical experiments, such as Johnson’s plasma transfusions. The anti-ageing market is expected to surpass $119.6bn globally by 2030.
As people live longer across the world and our societies age, there is a creeping societal pressure to reverse the visible (and biological) effects that come with each advancing year. Private companies recognise this, creating products that claim to bottle “youth”; the idea of returning to your prime and the fullness of life. We are surrounded by marketing and advertising that encourages us to seek out this elusive goal and tries to get us to spend money, from hundreds of pounds to millions.
I’m just as guilty as anyone of thinking how quickly life flies by as I approach 40. But I’ve changed my mindset from not wanting to age to taking steps to age as naturally and healthily as I can. For me, it is about maintaining functional health with each passing year: can my mind and body do the things that I want them to do, such as run 5km or solve Wordle? And can I avoid health conditions such as type 2 diabetes and hypertension that tend to come with being older and south Asian?
We don’t know how to “reverse” ageing, but decades of public health research have created an evidence base for how to live longer: don’t smoke, don’t drink too much, eat a diverse and balanced diet, avoid ultra-processed foods, try to move each day – even if just walking – and maintain muscle mass, and stay socially active with friends and acquaintances. Loneliness, especially for those aged 50 or older, has potential consequences, including a 50% increased risk of dementia, 29% increased risk of heart disease, 32% increased risk of a stroke and a significant increase in risk of premature death from all causes.
Medicine may some day provide the “cure” for the biological effects of ageing. Until then, a lot of the answers to living well as we age can already be found in public health research. And while getting older is often seen in negative terms, it is ultimately a marker of the success of our public health and medical systems that we are growing older as a species. In 1841, life expectancy at birth was roughly 40 years old. Forty wasn’t midlife: it was life. Ageing is simply a byproduct of living and living another year is cause enough to celebrate each birthday that comes.
Prof Devi Sridhar is chair of global public health at the University of Edinburgh