“Ready, on three,” Jamie Love said to the group of hikers as they huddled for a photo. “One, two, three …”

“Don’t die!” they shouted in unison.

The dozen or so strangers were gathered at the foot of Temescal Canyon Trail along the Pacific coast in Los Angeles on a cool Saturday morning in mid-December. Several of them, including Ms. Love, 38, who had organized the outing, wore black T-shirts with the bold white text, “DON’T DIE.”

The hikers had come together with a shared goal: to extend their life spans through diet, sleep, exercise and whatever technologies might come along.

Not present was the spiritual leader of the gathering, the internet celebrity and centimillionaire tech founder turned longevity guru Bryan Johnson. In the past year, Mr. Johnson has arguably taken the lead in the race among Silicon Valley rich guys going to extremes in a quest to live forever. (Move over, Messrs. Bezos, Zuckerberg and Thiel.) Now he’s turning that longevity mission — and the online infamy he has earned because of it — into a lifestyle business, selling supplements and prepackaged meals to less-rich people who would also like to live for a very long time. The hike, one of more than 30 “Don’t Die Meet-Ups” around the world that day, was a cross between community-building and a guerrilla marketing tactic.

Mr. Johnson’s deal, in a nutshell: In 2021, he began spending $2 million a year, by his own account, to measure every aspect of his body, from lipid levels to urination speed to brain plaque, with the goal of reversing his aging process. He called it Project Blueprint.

Every day, between 7 and 11 a.m., he eats the same three vegan meals: “Nutty Pudding” (a blend of nuts, seeds, berries and pomegranate juice), “Super Veggie” (black lentils topped with broccoli and cauliflower) and a third, rotating dish consisting of vegetables, roots and nuts. He exercises for an hour every morning and takes up to 111 pills a day. (His pharyngeal muscles may be the strongest of all.)

Mr. Johnson claims that his regimen (or “protocol,” as he calls it) has already slowed his speed of aging, giving him, at 46, the maximum heart rate of a 37-year-old, the gum inflammation of a 17-year-old and the facial wrinkles of a 10-year-old, according to his website. He publicizes his test results so anyone can see images of his bowels or learn the duration of his nighttime erections. His “biological age,” he claimed until recently, is 42.5, according to one measurement of changes in DNA over time known as an epigenetic clock. In other words, he has spent about three years shaving off — maybe — a little more than three years.

If the original goal of Project Blueprint was to perfect his health, Mr. Johnson now describes it as preparing humanity to thrive in a world dominated by artificial intelligence. Thus the new slogan: “Don’t Die.”

In an interview, Mr. Johnson said he didn’t care what present-day people thought of him. “I’m more interested in what people of the 25th century think of me,” he said. “The majority of opinions now represent the past.”

Mr. Johnson has an almost Trumpian ability to stay in the news. Since 2020, he has been the subject of five articles on Bloomberg documenting his quixotic pursuits: the brain-reading helmet developed by his company Kernel; his bid to become, as he has put it elsewhere, the “most measured person in human history”; his decision to receive blood plasma from his 17-year-old son and pass his own along to his 70-year-old father; and a recent round of experimental gene therapy in Honduras. In September, Time photographed Mr. Johnson in his private gym, naked but for a carefully positioned kettlebell — an instant meme. The New York Post has gleefully followed his every move, running more than a dozen articles on Mr. Johnson in the past year, including three about his penis.

On social media, where he has more than 700,000 combined followers on X and Instagram, he knows how to trawl for attention. He lists his stringent requirements for a romantic partner (8:30 p.m. bedtime, “no small talk,” “must give plasma”) and compares himself to religious figures (“Jesus fed bread and alcohol, impairing and aging/I will feed you nutrients that awake and create life”). His flat manner and uncanny looks have drawn comparisons to “American Psycho”’s Patrick Bateman, a “‘Lord of the Rings’ elf,” a vampire and a “jacked cyborg.” One podcaster called him “blood daddy.” He likes to pose in crop tops.

Now, Mr. Johnson said, after three years of self-experimentation — which he called “Phase 1” of Blueprint — he’s ready for “Phase 2”: helping others replicate his process. Late last year, he began selling Blueprint-branded olive oil. This month, more products, including powdered vegetables and pill supplements, became available on his website. In conjunction with the rollout, Mr. Johnson announced a “self-experimentation study” in which participants can pay for a starter pack of Blueprint products, as well as bloodwork and other tests to track their results. The 2,500 slots filled up within 24 hours.

To his fans, who fly across the country to meet him and haunt Blueprint message boards online, this moment is an exciting opportunity to spread the Johnson gospel. Some Blueprint advocates are even building businesses of their own around his ideas. To his detractors, it’s a cynical attempt to monetize his popularity. Or, worse: They call it pseudoscience that could harm the health of his followers.

The business is only one piece of the larger vision, Mr. Johnson insisted. If we can algorithmically orient the human body toward the single goal of not dying, then, he said, we can somehow extrapolate that process to the planet itself. “Climate change is an alignment problem,” he said. “Replace my body with planet Earth.”

So, in the meantime, why is he selling olive oil? And why are people buying it?

A Business, or a Cult?

Mr. Johnson grew up Mormon in Utah. Between college and business school, he worked for a credit card processing company selling services to businesses. His sales trick was to offer potential clients $100 for three minutes of their time. If they didn’t sign up for his plan, they could keep the money. He quickly became the company’s top salesperson.

In 2007, he founded his own payment processing company, Braintree, which acquired the startup Venmo and, in 2013, was itself acquired by eBay for $800 million.

A year later, Mr. Johnson got divorced and split from the Church of Jesus Christ of Latter-day Saints. “You’re born a baby again, having to answer these really important questions that don’t have any answers,” he said.

When I asked Mr. Johnson if he was building a religion, he said yes. “Belief systems have proven to be stronger than countries, or companies, or anything else,” for helping humans reach goals, he said. “Every religion has been trying to offer a solution to ‘Don’t die’ — that’s the product they’ve generated,” he added.

In conversations about Blueprint, it’s hard to avoid the word cult. Mr. Johnson himself likes to joke: “Is this some sick and twisted cult trying to get me to go to bed on time?”

Jeff Tang, who recently started a Blueprint-based meal prep company in the San Francisco area, said a lot of businesses “feel like cults at the beginning,” citing WeWork as an example.

Mr. Johnson’s acolytes fall into two general categories: the health and wellness seekers, and the tech crowd, which in recent years has become preoccupied with longevity.

Many Blueprint-curious attendees at the Los Angeles hike said they cared less about maximizing their life span than their “health span,” or healthy years. Some found the predictability of Mr. Johnson’s plan appealing.

“Self-control and discipline — he just takes it out of the equation,” said Sirish Pulusani, 40, who works at a longevity-based health clinic. He wore an Oura ring, a Whoop bracelet and an Apple Watch — all of which track bodily metrics.

Theresa Cowan, 36, said she wanted to eat natural food like Mr. Johnson’s, which she believes could have healing properties, as opposed to fast food, which “is creating death to our cells.” Ms. Cowan, who has worked as an actress and singer, brought her children Makayla and Samuel, 8 and 5, on the hike. She said she and Makayla planned to adopt the Blueprint protocol and make videos about it. (“You’d want to be particularly cautious about this for anyone under 18,” said Dr. George Kuchel, a professor of medicine at University of Connecticut who studies aging.)

Ms. Cowan added that she didn’t give her children vaccines or antibiotics. “I live my life against the grain,” she said.

A number of meet-up participants shared stories of trauma, often health-related. Mr. Pulusani grew up with a severe case of eczema. Ms. Cowan’s husband has a tumor in his bladder, and she hopes to persuade him to adopt the Blueprint way of life in order to heal, she said.

Four hundred miles up the coast, about 50 people — mostly young, mostly men — gathered on the same day for a Blueprint hike starting at Rockaway Beach south of San Francisco. It was a tech-y group: A former employee of Elon Musk’s brain implant company, Neuralink, was there, as were a handful of founders from Y Combinator, the start-up incubator. (One person who couldn’t make it threw himself a Blueprint-themed birthday party in San Francisco the next night, with olive oil shots and blood bags full of passion fruit tea.) Mr. Tang, the organizer, carried along a cardboard cutout of Mr. Johnson’s famous kettlebell photo.

Before the group set off, Mr. Tang gathered everyone on a grassy patch and posed a series of icebreaker questions, including whether they’d want to live forever. About half the attendees said yes.

The Scientific Community Has Concerns

Mr. Johnson occupies an odd place in the field of longevity research, which has attracted a surge of investment in recent years. If there’s a spectrum between scientific rigor and pure marketing, many experts argue Mr. Johnson is on the promotional end.

Dr. Nir Barzilai, a professor of medicine and genetics at Albert Einstein College of Medicine in New York and scientific director of the American Federation for Aging Research, has spent years studying healthy seniors he calls “super-agers” and has identified several genetic markers associated with longevity. He said he appreciated Mr. Johnson’s bringing attention to the longevity field.

“But is he contributing to it in a scientific way?” Dr. Barzilai asked. “The answer is no.”

For starters, he said, Mr. Johnson’s methodology is far from the one accepted by the scientific community for a century: clinical studies with large groups of people, some with treatment and others with a placebo, ideally double-blind. (What Mr. Johnson described to me as his new “clinical trial” is … not that.) And Mr. Johnson, to date, has experimented only on himself.

“Even if it works with him — which I don’t think it does — this unique person has unique genetics that probably are not applicable to a population,” Dr. Barzilai said.

Dr. Barzilai also questioned Mr. Johnson’s decision to adopt so many different interventions at once, making it impossible to determine cause and effect — not to mention creating a risk of harmful interactions among treatments.

According to Dr. Barzilai, Mr. Johnson sometimes conflates markers of health, like lung capacity, with markers of aging. “The fact that he’s doing better at things he’s trained for doesn’t make the rest of his body younger,” he said. Similarly, other markers that Mr. Johnson measures may correlate with age but haven’t been shown to cause aging or de-aging.

Dr. Barzilai was not particularly impressed with Mr. Johnson’s results, either. He himself is taking only metformin, a diabetes drug whose life-extending potential he has studied, and doing intermittent fasting, which has been shown to improve the life span of mice but not humans. But when Dr. Barzilai, 68, met Mr. Johnson at a conference in 2023, they took a blood test and got similar results: “We were both about three years younger than our age,” he said.

Experts are also skeptical of Mr. Johnson’s supplements regimen. Valter Longo, professor of gerontology and biological sciences at the University of Southern California, said taking a large amount of supplements risked adverse interactions.

“Some supplements may give you the nutrients you’re missing, but a lot, particularly in high doses, are likely to interfere with normal physiology and eventually do more damage than good,” he said.

Andrew Steele, a biologist and an author who writes about longevity, said there was no evidence that Mr. Johnson’s products would help people live longer. “None of them has slam-dunk human data saying this supplement or additive will improve life span,” he said.

A University at Buffalo dietitian, Danielle Meyer, said Mr. Johnson’s diet would be hard for many women to adopt. (Blueprint’s female chief marketing officer followed the full regimen for 90 days but has since switched to a less intense routine.) “Our life stages have different needs,” Ms. Meyer said. “Women of childbearing age, menopause — all these factors make it more complicated in females than in males.”

She also questioned the sustainability of the Blueprint program, pointing to research showing that rigid diets are difficult to maintain. (Mr. Johnson restricts his daily calories to 2,250, rather than the 3,000 that his body mass and exercise regime suggest he needs.)

Mr. Johnson acknowledges that it can be hard to tease apart the variables in his regimen, and that the changes he’s measuring with biomarkers have not been proved to cause aging or reverse it. But he dismisses experts who criticize him, calling them the “longevity mafia.”

Achieving scientific consensus is slow, he said: “You’ll die before you get that.”

An Ugly Legal Battle

In December, Mr. Johnson posted a video on YouTube titled “My Ex-Fiancée Sued Me for $9,000,000,” in which he responded to a lawsuit that the filmmaker and former actress Taryn Southern had filed after they separated in 2019. In a 2021 complaint, Ms. Southern claimed that Mr. Johnson had withheld money he owed her for work, and that after their breakup — after Ms. Southern was diagnosed with cancer — Mr. Johnson had failed to follow through on a promise to pay her rent and expenses for a year. Ms. Southern sought at least $1 million in damages.

Mr. Johnson denied all accusations and contested the lawsuit. An arbitrator decided that Ms. Southern was bound by a separation agreement she previously signed, in which she forfeited her right to sue Mr. Johnson. The arbitrator ultimately ordered Ms. Southern to pay Mr. Johnson’s legal fees.

In his YouTube video, Mr. Johnson framed the lawsuit as a shakedown — Ms. Southern’s lawyers had originally sought $9 million in a letter — and an example of “the dark underground accusation economy.” (Ms. Southern, who is bound by a nondisclosure clause in the separation agreement, declined to comment.)

A December article in Vanity Fair highlighted Ms. Southern’s side of the story. After she got cancer, Mr. Johnson called her a “bad deal” and a “net negative,” according to the complaint. Ms. Southern’s account portrays Mr. Johnson as emotionally manipulating her and dangling the prospect of stock options in one of his companies to pressure her into signing the separation agreement.

Mr. Johnson dismisses the Vanity Fair piece and critical threads about his behavior on X as “one-sided,” as they rely on Ms. Southern’s version of events. In an interview, he said that the anecdotes in the lawsuit were “entirely fabricated.” So far, he has declined to respond to Ms. Southern’s specific claims, arguing that it wouldn’t change people’s minds.

When I asked about the perception that he was controlling, Mr. Johnson told me that after his previous marriage had ended messily, he had insisted on having Ms. Southern — who also worked for his companies — sign agreements stipulating the terms of their arrangement for the sake of clarity.

“It had nothing to do with control, and everything to do with relationship hygiene,” Mr. Johnson said.

Blueprinters I spoke with said the case had not changed their opinion of Mr. Johnson. “I just scrolled right by it,” Ms. Love said. “It’s not something I want to put into my consciousness.”

The Blueprint Stack

Mr. Johnson calls his new bundle of products the “Blueprint Stack” — a coding reference that, like “protocol,” evokes the metaphor of human body as computer and life as algorithm.

Offerings include powdered versions of Nutty Pudding and Super Veggie, cocoa powder, and a dried mixture of nuts and blueberries. He is also selling a “Longevity Blend Micronutrient Drink Mix (Blood Orange Flavor),” which includes the supplement creatine and the New Age-favorite shrub ashwagandha, plus four different pill products, which altogether represent a simplified version of his 100-plus pill regimen. As a wink to his skeptics, he plans to rebrand his olive oil as “Snake Oil.”

The current basic package costs $333 a month, but that covers only about 400 calories a day. Mr. Johnson said he planned to offer enough products to account for a person’s entire daily calorie intake for less than $1,000 a month. (Adults typically need between 1,600 and 3,000 calories a day.)

“We’re trying to compete for the most nutritious food program in history,” he said. “Like, so good that it’s not crazy to say the U.N. should be using this.” Mr. Johnson is also talking to two companies — one providing a gene therapy, another that offers stem cells from young bone marrow — about arranging a discount for Blueprinters. “The idea is to create the Costco of the health and wellness industry,” he said.

Mr. Johnson puts the recipes for his meals on his website, so anyone can cook them — and sell them. After the hike in Los Angeles, the group gathered around a picnic table, where Adrien Cohen, 32, who recently founded a Blueprint-based meal prep start-up, distributed containers of Nutty Pudding and Super Veggie.

Mr. Tang, whose previous project was organizing “T-parties” where men gathered to measure their testosterone levels, said his meal prep company was serving 1,000 Blueprint meals a week in the San Francisco area. He said he planned to pivot away from the Blueprint branding, but for now it’s a “signaling banner for people who want to improve their health.”

Mr. Johnson said he was delighted that others were building their own businesses around Blueprint. However, he has trademarked the Blueprint name and said he might eventually try to work out licensing agreements with the other companies using it.

He declined to comment on his current net worth but said he was less focused on making money than expanding the reach of Blueprint. “This is not a money grab,” he said. (Mr. Johnson said that the business’s revenues so far total several millions of dollars, a claim that could not be verified.)

But, he said, he’s reaching the limit of experiments he can perform on himself. Hence the new “clinical trial,” in which volunteers will consume Blueprint products for three months and then get tested to measure the results. (Participants have to pay for the testing themselves, which amounts to $800 or $1,600, depending on the extent of testing.) There’s no control group, it’s short term, participants consume 67 different therapies at once, and they’re on the “honor system” to eat the Blueprint package and otherwise maintain their base-line diets.

Mr. Steele said that it’s unlikely the new study will yield useful data. “It will be impossible to know how much of any observed effect is real, or just the placebo effect,” he said.

Mr. Johnson concedes that the design is not that of a clinical trial that the mainstream scientific community will accept. “Will this trial end up being reputable? We’ll see,” he said.