Tech entrepreneur Bryan Johnson disclosed on Tuesday that his recent autoimmune gastritis diagnosis would have been significantly worse without his intensive five-year focus on health and anti-aging routines, according to an email exchange with The Independent.
The 48-year-old biohacker explained that his May diagnosis of autoimmune gastritis likely stems from an earlier diagnosis of autoimmune hypothyroidism at age 21.
According to the Cleveland Clinic, autoimmune gastritis is an incurable condition where the immune system attacks the stomach lining, affecting 0.5 to 2 percent of the U.
S. population.
The condition prevents the stomach from producing adequate acid to absorb iron, causing an 11-year deficiency that Johnson addressed by receiving an intravenous infusion of 1,000 mg of Monoferric.
Addressing public reactions regarding his health and multi-million dollar annual regimen, Johnson spoke out about his diagnosis and lifestyle choices.
"Had I not taken care of my body during the past five years, the situation would be much worse so I am very grateful to have been focused on health," Johnson wrote.
Johnson noted his iron absorption issues were directly connected to his stomach condition following treatment.
"I had low iron for 11 years," Johnson wrote. "I've finally boosted it back to healthy levels."
He further detailed how the digestive issue prevents normal nutrient uptake.
"With AIG, my stomach doesn't make enough acid to absorb iron," Johnson stated.
Defending His Health Regimen
Defending his strict health regimen against critics, Johnson challenged conventional cultural eating habits and social norms.
"The anesthesia only works if everyone does it together. One abstainer reveals to the room that they are drunk," Johnson wrote.
"This is the source of the anger. It's not my decisions.
It's their reflection in the mirror."
Clarifying his stance on personal health choices, he emphasized that his position was not a personal critique of others.
"I'm agnostic to what you do and why you do it," Johnson wrote.
The subject of the 2025 documentary Don't Die: The Man Who Wants to Live Forever stated that untested individuals often maintain an unfounded view of their physical status.
"For those who do not routinely measure their health, that ignorance manifests a false sense of physiological superiority," Johnson wrote.
Johnson dismissed online suggestions advocating simple remedies like sunlight or dietary shifts to solve autoimmune disorders.
"These are unlikely," Johnson wrote.
Johnson initially disclosed on June 30 to his 1.6 million social media followers that his stomach was failing due to the disease.
"I'm going to try and solve it. Will share all," he vowed.
Reflecting on his youth, Johnson attributed his medical history to early dietary choices, high stress, and weight gain prior to adopting biohacking.
"As a kid, I ate sugar cereal, drank sugary soda, and gobbled down fast food," Johnson said.
"I had a few healthy years in my early 20s but then became a young father of three and began building a business.
Juggling that stress and grind, I let my health slip and gained 40 lbs. Within a few years I'd fallen into a deep, chronic depression.
Somewhere in that timeline, my body began developing an autoimmune process affecting my thyroid and then my stomach lining."
He recounted that his immunological markers originated early in life.
"My body's genetic and immunological architecture made a mistake decades ago, failing to distinguish between my own tissues and external threats," Johnson wrote.
"Trying to cure a decades old, genetically driven, antigen specific immune failure by switching to a meat diet or getting sunlight is like trying to fix a corrupted line of software code by altering the temperature of the room."
Johnson addressed frequent unsolicited social advice regarding his intense commitment to longevity.
"I don't intend to live a little.
I intend to live more than any human who has yet lived and invite you to join me," Johnson wrote.
