A millionaire who has spent a large amount of his fortune on anti-ageing has been diagnosed with an incurable disease.

Bryan Johnson, a tech entrepreneur famous for spending nearly $2million (€1.75m) a year to reverse ageing, revealed last week that he has been hit with a devastating health battle.

The millionaire shared that he has been diagnosed with autoimmune gastritis (AIG), a rare condition in which the body’s immune system attacks the stomach lining.

The 48-year-old revealed the news on X, writing that his ‘stomach is eating itself’.

Johnson warned that the illness affects approximately 2 to 5% of people, often developing silently to lead to iron deficiency, anaemia and an increased risk of stomach cancer if left undetected.

He wrote: ‘I’m going to try and solve it. Will share all.

‘As a kid, I ate sugar cereal, drank sugary soda, and gobbled down fast food. 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.’

Johnson said he ‘overhauled’ his medical team before discovering the illness, after he had gone through a series of health exams.

He added: ‘You too may have a lurking health issue that is undiagnosed and could increase in severity from unhealthy life choices, without your knowing. The absence of symptoms is not the presence of health.

‘A gentle nudge that minding your health, no matter your situation in life, is good decision making.’

Johnson has previously made global headlines with his extreme longevity experiments, attempting to ‘conquer death’ and live longer than anyone has lived before.

Explaining his approach to life in another post, the biohacker said that he is ‘not opposed to pleasure’ but he wants to ‘say no to the dying ritual’.

He stated: ‘The reward is a clearer lens, the ability to see what is currently invisible. High resolution consciousness allows for depths of thought, creativity, and experiential variance that are far harder to reach when the brain and body are chronically inflamed, degraded, and sedated. I want to expand the boundaries of the human experience.

‘On offer in this new future are things that no human has ever tasted before. I’m not deprived by the lack of participating in the rituals, I’m pointing to a joy that the human mind has not yet imagined.

‘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.’