How close are we to living forever – and do we want to?

Even if you don’t know his name, you’ll know of him: Bryan Johnston, the man who wants to live forever. The 48-year-old tech billionaire from California, and subject of Netflix documentary Don’t Die, spends $2million every year trying to reverse his age.

This includes taking a huge range of vitamins, minerals and herbal supplements, a strict 1,950 calorie diet, cosmetic procedures, prescriptive exercise regimes, regular tests to monitor how his brain and body is performing, and experimental treatments including an infamous blood-plasma exchange with his teenage son.

On the other side of the Pacific Ocean, Russian president Vladimir Putin was recently overhead telling Chinese president Xi Jinping that “human organs can be constantly transplanted, to the extent people can get younger – perhaps even immortal”. Xi replied that living to 150 may be possible by the end of this century.

But are we actually getting any closer to living forever – or at least a lot longer than we ever imagined?

How long could we live for?

How many years do scientists currently estimate we could be around for? Professor João Pedro de Magalhães from the University of Birmingham, believes humans could live for 1,000 years. And if the tech arrives that eliminates ageing at a cellular level, he says we could be celebrating our 20,000th birthday.

Taking things one step further, Google AI visionary and ‘futurist’ Ray Kurzweil says we can cheat death – we just need to merge our brains with AI. And he predicts this will happen in the next 10 years. “In the 2030s, robots the size of molecules will go into our brains, non-invasively, through the capillaries, and connect our brains directly to the cloud. Think of it like having a phone, but in your brain,” he says. By 2045, this will lead to a version of immortality, where our brains ‘live’ forever in new bodies built from 3D-printed parts.

However, Venki Ramakrishnan, author of Why We Die: The New Science of Aging and the Quest for Immortality, believes humans won’t live much further than 110 and we’ve only got this far thanks to improvements in public health and medical advances in treating age-related conditions, rather than any advances in longevity. He says, “There’s a natural limit of our biology because lifespan for each species is a result of evolutionary selection.”

The cure for ageing

But whether we want to live to 110 or 20,000 – we'll need to find a way to limit ageing in order to get there. The race to find a ‘cure’ for ageing is now so intense, there’s even a $101million prize for the scientists who find a way to “dramatically rejuvenate our muscles, cognition and immune functions”.

Why are scientists so keen to limit ageing? It's not just a vanity project, there are health benefits at the core. As we get older, certain things start happening inside our bodies. Our DNA changes, cells stop dividing as normal, and waste products (the result of cellular activity) start to build up. Over time, this has an impact on our physical and mental health, increasing our risk of diseases including diabetes, heart disease, cancer and dementia. If we can stop – or at least delay – the ageing process, we could help prevent these age-related diseases from developing.

The latest advances in longevity

So what steps are scientists taking to try and turn back time – and how close are they to working? Currently, there are a number of groundbreaking research areas scientists are focusing on in a bid to improve our longevity.

Cell senescence

Senescent cells are cells that stop dividing but don’t die, instead releasing chemicals that trigger inflammation and age-related conditions like cancer. Finding a way to remove these senescent cells could help stop the damage they cause.

So far, research has found clearing out senescent cells in mice can ‘reverse’ the ageing process – improving cognitive function and energy levels, for example – and various clinical trials are now happening in humans. The results will help develop senolytics, a new class of drugs that can clear out different types of senescent cells.

Gene therapy

Another promising area of research is gene therapy, specifically ‘cellular reprogramming’. This is based on the work of Japanese scientist Shinya Yamanaka and his team who identified a certain series of genes that could turn cells in our body back into stem cells, which can then become any type of cell.

Cell rejuvenation is the goal of Altos Labs, the $3billion biotech company that counts Jeff Bezos among its investors. It’s rumoured that Altos Labs are about to move into human clinical trials, but it’s not yet known what – or who – they might be testing.

Drug repurposing

The third area that shows a lot of potential is drug repurposing – using existing drugs to target the issues caused by ageing. One of these drugs is metformin, which is normally used to treat diabetes, and another is rapamycin, which is currently used as an immunosuppressant.

Many of these drugs are ‘off patent’ meaning they were originally designed to treat a certain health condition, but that patent has now expired so other pharmaceutical companies can make and sell generic versions of the same drug. “But these drugs have been off-patent for years, so you would need a completely fresh set of clinical trials if you were going to use them preventatively for the diseases of old age,” says Professor Linda Partridge from the Institute of Health Ageing at University College London. And new clinical trials need a lot of investment.

What about ‘alternative’ treatments?

Back to Bryan Johnson – will anything he’s doing actually advance the science of longevity? His critics point out that his extreme regime of supplements, exercise, a strict diet and constant monitoring of his health metrics (a protocol he calls Blueprint) is incredibly expensive and unavailable to the overwhelming majority of us.

Another issue is that because he’s ‘testing’ so many different interventions, it will be hard to tell which one actually worked if he does manage to live forever. And because he is the only subject in his ‘study’, his results probably won’t apply to the rest of the human population.

And what about Putin’s idea to constantly replace worn-out organs to achieve immortality? The big issue is people who receive donor organs have to take strong anti-rejection drugs that can have severe side effects, including high-blood pressure and an increased risk of diabetes. We may not be able to cope with multiple doses.

Plus, undergoing major surgery is a risk to your health at any age, let alone as we get older. Professor Neil Mabbot, an expert in immunopathology at the University of Edinburgh, says, “As we age, we respond less effectively to infections, and our bodies become more frail, prone to injury and are less able to recover and repair.”

We could skip replacing body parts altogether and go for a full body transplant instead: putting your head on a much younger body. This is still wildly theoretical, but scientists believe the shock of adjusting to living in someone else’s body would ‘prove too significant to maintain personal identity’. In other words, you would no longer be you.

But none of these answers address a key element in the debate over longevity – why would anyone want to live forever?

Why do humans want to be immortal?

Some of this desire to cheat death may come from a fear of death itself; wanting to avoid dying is a basic survival instinct. But rather than making sacrifices to ancient mythical gods, we can now invest in cell rejuvenation or gene therapy.

Another perspective is that we are terrified of ageing because we know how society treats older people. Fears about getting ill or frail, or becoming lonely and isolated, drives anxiety around ageing and leads to ageism. In fact, ageism can shorten our lives because it means older people receive worse healthcare and face more financial, phycological and physical abuse than younger people.

Fighting these views needs a two-pronged approach – finding ways to help us stay healthier for longer (known as ‘healthspan’) so older people are no longer seen as a ‘burden’, and tackling ageism. If we know we can live long, healthy and useful lives, becoming immortal may no longer seem so important.

What does improve our healthspan?

Many scientists studying longevity say this is the real goal – figuring out how to add healthy years to our lives rather than simply living for longer. And the three things Bryan says have had the biggest impact on his health are also areas that have been widely researched and could be achievable for the rest of us.

Sleep

A decent night’s sleep does more than help you feel refreshed when you wake up. It can also clear out waste products from your brain, improve your memory, balance out your hormones, repair and reset your body, maintain your immune system and generally support your overall wellbeing to live a long and healthy life.

Bryan’s tips for better sleep include sticking to the same bedtime every day, avoiding bright light before sleep, and creating a wind-down routine to avoid overstimulation before bed i.e. no coffee or doomscrolling. These are better known as good sleep hygiene behaviours, and are easily achievable for everybody.

Diet

We know Bryan follows a calorie-restricted diet and there is evidence to show that reducing calories can boost longevity. However, a lot of these studies have been done in mice or fruit flies. Human trials have been carried out, but they are not big enough to conclusively say whether this is an approach we should all follow.

Bryan also practices intermittent fasting – he eats his last meal of the day at 11am and fasts for 18 hours – and some human studies do show that this can help reduce our risk of age-related conditions like diabetes and heart disease. But (again) we don’t yet know if this will work for everyone.

Bryan’s other diet tips include eating whole foods, healthy fats, quality proteins and avoiding sugar; essentially a Mediterranean diet. This type of diet does have well-known health benefits, including reducing our risk of high blood pressure, stroke, heart disease and other cardiovascular conditions. A Mediterranean diet is also rich in fibre, which can help support a healthy gut microbiome. And new research is now emerging that suggests increasing the number of beneficial bacteria in our gut could also increase our healthspan.

Exercise

If you thought Bryan devotes huge chunks of his day to gruelling workouts, you’d be wrong. He does spend one hour a day exercising, but this is usually a mixture of strength, cardio, flexibility and balance training – all intensively monitored, of course.

For those of us who don’t have a $10,000 anti-ageing home gym, he recommends just 30 minutes of exercise a day, like running, swimming or cycling to get your heart rate up. He also advocates moving every 20-30 minutes throughout the day.

We know sitting for too long can lead to serious conditions including cancer, diabetes, depression and obesity. But breaking up the day with light activity, such as taking walking breaks away from your desk, or doing some gentle stretches during the adverts, can help counteract the effects of sitting down for hours.

The search for immortality

While tech start-ups and longevity influencers look for a key to immortality, we might already have the answer to a long and healthy life. “If you look at health inequalities across the UK, you can get a 10-year difference in life expectancy even between different parts of the same city,” says Prof Linda Partridge.

She points out that exercise is really important for healthy ageing, but if you don’t have enough time, opportunity or the space available, you’re less likely to exercise. A healthy diet is another factor, but ultra-processed foods (UPFs) can be a lot cheaper than fresh, wholefoods, especially if you’re on a strict budget.

Rather than trialling expensive treatments or looking for a science-fiction cure for ageing, “we need to tackle some basic socioeconomic issues first,” Prof Partridge says. “Supercentenarians are very interesting, but there’s something much more important right in front of us we need to deal with.”

These socioeconomic interventions may have as big an effect on our longevity as new research or discoveries into the mechanics of ageing. But that’s never going to grab as many headlines – or attract billions of dollars of investment – as melding our minds with AI or undergoing a blood-plasma exchange with our offspring.