The Story of the Human Body addresses common contemporary health concerns and provides suggestions for improving personal and public health. Lieberman covers a number of diseases which are prominent in modern society, some of which are leading causes of death, including heart disease, some cancers, and diabetes. He also incorporates a table of potential mismatch diseases which lists 49 ailments, including acne, anxiety, cavities, depression, myopia, hemorrhoids, flat feet, endometriosis, carpal tunnel, diaper rash, high blood pressure, impacted wisdom teeth, and insomnia. These are all extremely common conditions that arise in modern individuals.

Along with identifying prevalent mismatch diseases, Lieberman proposes potential ways to prevent or mitigate these conditions on personal and societal levels. Health is a culturally trending topic, and most popular advice, including professional advice, focuses on the individual living within the modern environment. Lieberman contributes to health discussions by offering a unique evolutionary perspective. He asserts that understanding humans’ biological and cultural evolutionary past is critical for addressing some of the most pressing health concerns. To understand why the body develops lifestyle-related diseases, he argues, one needs to understand what environments and behaviors the human body is adapted, or maladapted, for.

While he targets modernity as a primary cause of numerous diseases, Lieberman does not advocate for the rejection of modernity or for the return to hunter-gatherer or early agrarian lifestyles.