Millionaire biohacker Bryan Johnson, 48, has disclosed that he is suffering from an incurable autoimmune disease called autoimmune gastritis (AIG), which causes his body to attack its own stomach lining. In a social media post, Johnson stated, "My stomach is eating itself." AIG is an autoimmune disorder where the immune system targets the stomach's acid-producing cells, potentially leading to vitamin B12 deficiency, anemia, and an elevated risk of stomach cancer.
Johnson's Struggle with Chronic Depression and Low Ferritin
Johnson wrote on X that he had fallen into a deep, chronic depression over several years, during which his body developed an autoimmune process affecting his thyroid and stomach lining. He only became aware of the condition in May and is uncertain how long it has been present. "I'm unsure how long I've had it. AIG causes irreversible damage: nutritional deficiency, anemia, and over a long horizon, elevated cancer risk," he said.
For 11 years, Johnson experienced low ferritin—a protein that stores iron—but did not have anemia. He attempted various methods to raise his iron levels without success. He now recognizes that low ferritin was an early indicator of AIG, noting that "low ferritin was easy to dismiss by most standards of care."
Symptoms and Challenges of AIG
Symptoms of autoimmune gastritis include abdominal pain, iron deficiency, loss of appetite, nausea, and unexplained weight loss. However, these symptoms are not unique to AIG, making diagnosis difficult. Johnson admitted to fans that "there's no approved cure for autoimmune gastritis today," but he plans to work with his team to find a cure.
Johnson expressed optimism about modern technology, stating, "In the age of AI, multiomics, and custom-built DNA, proteins, and cells, no condition should be presumed incurable simply because no one has yet tried to cure it with today's stack."
