Harvard professor evaluates popular diets in new book Fed Up

Harvard University biological sciences professor Daniel Lieberman has entered the crowded arena of diet discourse with his new book Fed Up, which seeks to separate scientifically supported nutrition advice from fleeting social‑media trends. Drawing on his expertise as an evolutionary anthropologist, Lieberman examines popular regimens such as paleo, keto, raw food and intermittent fasting, testing each on himself to assess their health impacts and long‑term viability. In a recent interview with Guardian science editor Ian Sample, he explained how the research and personal experiments informed the book’s central argument that many contemporary diets overlook the evolutionary context of human metabolism.

Lieberman disclosed that, after trialing a range of eating plans, one particular approach has endured in his daily routine, though he did not name it explicitly in the excerpt. Fed Up is available for purchase through the Guardian Bookshop, with proceeds supporting the publication. The book aims to provide readers with a clear, evidence‑based framework for evaluating diet claims amid the proliferation of online nutrition fads.