India, July 7 -- American tech entrepreneur Bryan Johnson, famous for spending nearly $2 million a year on biohacking and to reverse ageing, recently revealed his diagnosis of Autoimmune Gastritis (AIG). In a lengthy X post on July 1, the 48-year-old wrote: "I have an autoimmune disease. My stomach is eating itself." The good news, he said, was that he would try to solve it. AIG is a chronic disease where the body's immune system incorrectly identifies the stomach lining and the cells responsible for producing gastric acid as a threat to the body. This eventually leads to a reduction in the production of gastric acid, affecting absorption of key nutrients like vitamin B12 and iron, resulting in anaemia and other possible complications, explains gastroenterologist Dr Ronak Tate....