Mosley was a medical school graduate who joined the BBC as a trainee assistant producer in 1985. He quickly found himself able to communicate groundbreaking scientific and medical ideas to mass audiences, a skill he used to great advantage time and time again.
In 1995 the British Medical Association named him medical journalist of the year thanks to his Horizon episode Ulcer Wars, spotlighting the medical profession’s hesitance to follow research that ulcers were caused by the bacterium Helicobacter pylori and could be treated with antibiotics rather than surgery.
In 2014, for example, he mimicked their approach to research by swallowing three tapeworm cysts that he obtained from infected cattle to see what they did to his body, for a BBC Four series. He remained asymptomatic but gained a kilo in weight, possibly due to his increased appetite. Although the 5:2 diet was not his discovery, Mosley popularised it to such an extent that he was able to write a number of highly successful books on the subject. His ideas would later evolve to become what he termed the Fast 800 diet, a low-calorie, low-carbohydrate Mediterranean diet that also included intermittent fasting. Again, the books he wrote on the subject became minor publishing sensations, thanks in part to Mosley’s willingness to walk the walk when it came to sharing big ideas.