Bryan Johnson knows that you think he is weird. So much of his life occurs outside the realms of what most people consider normal that it would be odd if you didn’t. He rises at 4.30am, eats all his meals before 11am, and goes to bed – alone – at 8.30pm, without exception. In the intervening hours, he ingests more than 100 pills, bathes his body in LED light, and sits on a high-intensity electromagnetic device that he believes will strengthen his pelvic floor. This is all done in the service of slowing his rate of ageing until, he hopes, one year of chronological time can pass while his biological age stays the same. His ultimate goal? “Don’t die.”

Oh, and, incidentally, he wants as many people as possible to join him.

Obviously, not everyone is jumping on board. Plenty of longevity experts will tell you that the human body can’t be hacked like that, while an array of social media commenters tell Johnson that he looks older than his 45 years, or say they hope he gets hit by a bus. So far, none of this has deterred Johnson, who has spent two years fine-tuning what he calls Blueprint, a system of behaviours designed to take better care of him than his own mind can. He also shares the (exhaustive, and exhausting) details online, so that anyone who wants to can follow the process, for far less than his reported outlay of $2m (£1.6m) a year.

Johnson is not starting his anti-death quest from optimal circumstances. He sold his company, Braintree Venmo, to PayPal in 2013 for $800m – the sort of money most people assume would fix everything in their lives – but spent much of the following decade overeating, drinking too much and dealing with depression. This, he says, is why he now thinks in terms of algorithms. “What I said about myself is: do I really think that I can live my best life on my own?’” he says, speaking to me from his minimalist home in Los Angeles, where the air is filtered and the shelves are lined with greenery. “And I decided that, no, I can’t. I just don’t have what it takes. I really need this augmentation.”

These days, Johnson refers to himself as “the world’s most measured human”. His team of doctors and health experts are constantly monitoring everything his body does, from his cholesterol levels to the length of his telomeres – DNA “caps” that prevent our chromosomes from fraying, like the plastic tips on shoelaces, and are thought to play a key role in cell death and ageing. This all feeds into a system that tells him how to improve those measurements. “We’ve basically crawled every scientific publication on healthspan and lifespan – something like 2,000 publications,” he says. “And we take each study, apply a number of criteria to it – some are animal models, so we make that discernment – and then we prioritise.”

Where this has led him is to a lifestyle that, understandably, many people aren’t keen to follow. Two of the three meals he eats every day are exactly the same: “super greens” features boiled broccoli, cauliflower, mushrooms and garlic, while “nutty pudding” includes chia seeds, macadamia nuts and berries. He takes 54 pills in the morning, and the rest in between skin treatments, red-light therapy and more measurements. He routinely lives in a calorie-restricted state, doesn’t drink alcohol, and doesn’t go out in the evening, ever. More reassuringly, he also abandons things when they don’t work: he has taken human growth hormone, for example, but stopped because the potential side-effects were too egregious. He also experimented with taking blood plasma from his 18-year-old son Talmage – paying it forward by donating some of his own plasma to his 70-year-old father – but abandoned that because of a lack of results.

It is also worth noting, however, that much of what Johnson does is based on well-accepted science. His fitness regime, for instance, includes a mixture of resistance training and cardiovascular work calculated to improve his VO2 max (the maximum amount of oxygen his body can take in while exercising) – both of which are linked to significant reductions in mortality. There isn’t a ton of good evidence about the effect of sleep quality and duration on mortality, but there is broad agreement that they are probably important. And whatever you think about eating steamed and pureed lentils and broccoli, they undeniably contain more phytonutrients than pizza.

Is Johnson’s regime working? It depends on how you define success. For him, the measurements are going in the right direction. His VO2 max of 58.7ml/kg/min would be impressive for a much younger man, and plenty of his other biomarkers are better than would be expected for a 45-year-old. His “sleep performance”, according to the trackers he uses, has been perfect for six months. He can bench press more than 100kg, and has less than 7% body fat. One of the strongest criticisms of his regime, though, is that while he is improving on the typical biomarkers of age – strength, bone density and hair thickness – he is not slowing ageing in any meaningful way.

“People have the gene set that we have, which limits our lifespan,” says Dr Charles Brenner, a biochemist who studies longevity and ageing. “There’s nothing in Bryan Johnson’s protocol that would change his maximal lifespan. There are people who aged remarkably well and lived for 110 to 122 years. None of those people had highly regimented practices like that of Johnson. One can say that he’s put himself on a better ageing trajectory, but one cannot say that he has reversed or eliminated ageing.”

What about the other criticisms? The most common are that his life must be miserable, that an existence without pizza, beer and late nights seems like no existence at all, that he could do all this for years and then be hit by a bus. Johnson has that covered, too: “Whenever I get in my car, I say to myself: ‘This is the most dangerous thing I’ll do today’” – and genuinely doesn’t seem to care about pizza or beer. A divorcee, he acknowledges that romance will be difficult, with his stated “first-date expectations” including “u sleep alone” and “no small talk”, and has no intentions of changing his rigorous sleep schedule if it hampers his sex life.

He also seems to have a lot of fun: he is engaged in a table-tennis rivalry with Talmage, and has friends, he says, who are respectful of his routine. This is something I am curious about, because one common feature of the world’s “blue zones” – where people tend to live longer than average – is a highly social culture. Is that something he takes into account? “We do work on a lot of things we don’t talk about, because I’m still at the stage of establishing credibility,” he says. “We do that by talking about things that are agreed on. When you get into areas that don’t have that kind of rigour and agreement, then it’s harder.”

What about the flip side of social support? Johnson frequently – and merrily – spars with his most vicious critics on X (formerly known as Twitter), and as a frequent user of the platform myself, I’m only too aware that it can take me from upbeat to enraged in seconds. Do the haters not throw off his routine? “The troll inside my head is much more vicious than the trolls I get online,” he says. “When I was depressed and my brain would constantly say to me, ‘Life is hopeless,’ I had to basically say, ‘I don’t care what you’re going to say.’ And ultimately, it lost its power. And I’ve seen that happen as people troll me and I play with them. Like, it’s honestly not even interesting any more.” Does he worry that it’s affecting his life – his stress levels, for example – in ways he’s not aware of? “Absolutely. We do use proxies for that – looking at my stress levels, looking at my sleep quality and a whole bunch of other stuff to basically try to assess whether anything in my life is creating unhealthy conditions. It’s a legitimate question.”

Johnson says he is doing this for everyone, but this is where another issue comes in. He is planning to make a “low-cost and easy” version of Blueprint available soon to anyone interested, and is already selling his own brand of olive oil – although he stresses that profit “was never the objective when we started”. But any number of far simpler health measures – regular exercise, eating lots of greens, consistent sleep – have copious evidence to back up their efficacy, yet far too few people bother with them. So how is there any hope of getting the general population invested in longevity?

For Johnson, this all ties back into his early experience as an entrepreneur. “When I was building my payments company, Braintree, the online payments experience was awful,” he says. “So you’d get a cab, and the wifi connectivity wouldn’t work, and it was just awful. And we said: ‘OK, let’s make this a beautiful experience.’” His intention is to do the same with health – taking out the friction and self-discipline, and automating the process in line with his own algorithmic thinking. “Ultimately, I’m not telling people to be more disciplined,” he says. “We’re insane right now in that we are addicted to addiction: food, porn, social media, alcohol, whatever. Blueprint is about acknowledging that it’s not reasonable to ask the individual to get their shit together when they’ve got a thousand things within two miles of them that have heroin-like dopamine highs.”

Obviously, there is something very Silicon Valley tech-bro about Johnson’s life – the obsession with measurement, the relentless drive for optimisation, the treatment of ageing as an engineering problem to be solved – but it also dovetails with a lot of things we already know and do. I know, for instance, that it would probably improve my life if I could avoid occasionally eating an entire packet of custard creams in one go, or go to bed at a reasonable time every night. I lift weights and run because I like doing it, but I eat watercress when I don’t really want to because I’d like to be around to see my son grow up. And whatever you think of this one man’s (OK, yes, slightly obsessive) quest to beat the reaper, he is right about the way the odds are stacked against us: all the bad stuff has great PR, while broccoli barely gets a look in.

Towards the end of our chat, Johnson asks me what I think of all this. Do I think “Don’t die” is a plausible concept? This is something I’ve been pondering a lot, after 15 years of writing about health and fitness, and so I tell him what I think: if we can dodge the bullets of climate crisis, nuclear war, a much worse pandemic, or the other hundred things that might kill us, a world where we’re not limited by traditional human ageing seems … at least possible. This might seem sacrilegious, but, a few hundred years ago, so did the idea that humans would one day be able to travel faster than a horse or sail would carry them, or talk to someone on the other side of the world. If human progress continues on its current trajectory – or we can work out how to build a self-improving AI without it deciding to turn us all into paperclips – it doesn’t seem implausible that we will one day untangle our telomeres and make ageing an inconvenience rather than an inevitability.

Where I differ from Johnson, I think, is on timelines. Ageing, it is probably fair to say, comes with complexities we barely even understand, and so I am not sure whether this is all going to take 30 existential-disaster-free years or 300. Johnson seems reasonably confident that it can happen in our lifetimes – which is why he is so keen to stick around for it.

And what if it doesn’t? Assuming he can’t crack the whole thing and stick around past a normal human lifespan, what would have to happen to make him content to say goodbye? He hardly stops to think about the question. “I’d like to get hit by a bus,” he says, smiling with teeth that, apparently, score near-perfectly on his dentist-approved plaque index. “I’d like my death to be as entertaining as possible for everyone involved.”