Biohacker Bryan Johnson diagnosed with autoimmune gastritis amid quest to extend lifespan

In July 2026, 48-year-old biohacker Bryan Johnson announced he was diagnosed with autoimmune gastritis, an incurable condition where the immune system attacks the stomach lining. Johnson, who spends $2 million annually on his 'Project Blueprint' longevity regimen, links the condition to his childhood diet, stress, and a thyroid diagnosis at age 21. Despite standard medical consensus that the disease is only manageable, Johnson plans to use advanced diagnostics, immune cell sequencing, and experimental therapies to find a cure.

Bryan Johnson autoimmune gastritis diagnosis

• ▪Bryan Johnson was diagnosed with autoimmune thyroid disease at age 21, a condition he links to his recent autoimmune gastritis diagnosis
• ▪Bryan Johnson attributes his autoimmune conditions to a childhood diet of fast food and sugary drinks combined with later life stress
• ▪In July 2026, 48-year-old biohacker Bryan Johnson announced he was diagnosed with autoimmune gastritis, an incurable condition where the stomach lining is attacked
• ▪Bryan Johnson plans to attempt to cure his autoimmune gastritis using diagnostic monitoring, immune cell sequencing, and experimental treatments

Autoimmune gastritis pathology

• ▪Autoimmune gastritis is a chronic inflammatory disease where the immune system mistakenly attacks the acid-producing parietal cells in the stomach lining
• ▪Autoimmune gastritis impairs the body's ability to absorb vitamin B12, which can lead to nutritional deficiencies and pernicious anemia

Disease prevalence rates

• ▪Autoimmune gastritis is often underdiagnosed because it can remain hidden in its early stages, meaning actual prevalence rates may be higher
• ▪Autoimmune gastritis is estimated to affect between 2% and 5% of the population, though millions of people worldwide are affected

Symptoms of autoimmune gastritis

• ▪Autoimmune gastritis can remain asymptomatic for years, with chronically low iron or ferritin levels often serving as the first indicator
• ▪Symptoms of autoimmune gastritis can include burning upper abdominal pain, nausea, vomiting, bloating, and an abnormal feeling of fullness after eating

Diagnostic methods for detection

• ▪Bryan Johnson's autoimmune gastritis was diagnosed following a medical workup that included a colonoscopy, an upper endoscopy, and stomach biopsies
• ▪Blood tests showing elevated anti-parietal cell antibodies can serve as a diagnostic marker for detecting autoimmune gastritis

Cancer risk from gastritis

• ▪Autoimmune gastritis increases the long-term risk of developing gastric cancers and neuroendocrine tumors in the stomach
• ▪Approximately one in five patients with autoimmune gastritis will develop a neuroendocrine tumor in the stomach due to elevated gastrin levels