A revelatory and optimistic new book from health journalist Dr David Cox, examining the staggering impact of diet on ageing – and what we can do to reverse it.

Most of us are ageing prematurely because we’re eating too much of the wrong stuff.

Unlike our leaner ancestors, the 21st century human is a junkie for sugar, artificially synthesised foods and convenience meals. Despite the rise of plant-based diets we remain overwhelmingly carnivorous and nutrient-deficient, putting our bodies under relentless stress at a cellular level. Our habits are driving an epidemic of obesity and chronic illness that is overwhelming our healthcare systems and causing an acute global crisis.

Yet there is hope. Just as we're learning more about the effects of destructive diets consisting of UPFs and AGEs, we're also developing a new science of food that might save us. Dr David Cox meets a cast of academics, tech entrepreneurs and policymakers that illuminate the new frontier of longevity – a fast-growing area of scientific research and a budding commercial industry backed by the ultra-rich and powerful. We follow David’s journey to improve his biological clock as he undergoes a series of cutting-edge tests to understand how these technologies work, alongside easy fixes like increasing our fibre intake, using different cooking methods and reducing overall consumption.

We Are What We Eat is a fascinating and revelatory trip down the rabbit hole of nutrition science and biological ageing that pinpoints why our eating habits must change and how we can all slow down the ageing process to live longer and healthier lives.