Lifespan

For decades the medical establishment has held that nobody really dies of old age, only of age-related diseases, because ageing itself is simply inevitable. Dr. David Sinclair, a leading authority on genetics and ageing, asks whether that view is mistaken. What if ageing is a disease, and a curable one? His life's work has been aimed at more than a longer life: he wants people to stay healthy and free of disease well into their hundreds.

Lifespan sets out a bold new theory of ageing. Sinclair traces its root cause to an ancient genetic survival circuit, one that pauses reproduction so the genome can repair itself and that helped early single-celled life survive and evolve. The same circuit, he argues, is why we age. As UV rays, environmental toxins and poor diets pile up damage, the genome becomes overwhelmed, and the result is grey hair, wrinkles, sore joints, heart trouble, dementia and eventually death.

But he insists genes are not destiny. We cannot rewrite our DNA, yet we can influence the epigenome and so draw out the real potential of our genes. Drawing on his own research, Sinclair lays out a route to turning back the genetic clock by switching on what he calls vitality genes. Lifestyle changes such as intermittent fasting, eating less animal protein, cutting back on sugar, avoiding x-rays, exercising at the right intensity and trying cold exposure are among the steps he describes.

The book closes by looking ahead to a world in which people routinely live to 120 or beyond, and to what society would need to change to cope. Sinclair presents the supposed limits of human potential and mortality as choices rather than fixed facts.