Why everything you think about living to 100 might be wrong

While healthy eating and regular workouts are certainly good for us, many scientists now believe that genes rather than lifestyle are the determining factor in how long we live

Tech entrepreneur Bryan Johnson is talking about 16th-century sailors. Back then, he says, circumnavigating the globe was the height of human achievement. But those sailors, some of whom were coincidentally hoping to find a mythical fountain of youth, left port without knowing what really lay ahead. The same is true for Johnson, 47, who sees himself as a modern-day explorer. Like those sailors, he too is pushing the bounds of what is humanly attainable. Not by circumnavigating the globe, but by circumventing death.

Johnson's odyssey involves ingesting 111 pills a day, eating his last (vegan) meal of the day at 11am, staying teetotal, doing an hour of exercise daily and going to bed at 8.30pm. But is it scientifically possible to slow our ageing like this? Or is his plan more likely to end up shipwrecked by reality?