Geographic differences and secular trends offer important clues to the causes of disease. Unfortunately trends change, and geographic differences tend to be complex. Consequently the selection of single causes to explain diverse conditions is simplistic. Donnison, in Civilization and Disease (1937), designated cardiovascular disease, diabetes, hypertension, obesity, gallstones, and appendicitis, to name a few, as consequences of the stress of modern life. This book on western diseases, which is a long overdue sequel, suffers from the same unifactorial inference of cause, replacing diet for stress. The crux of the hypothesis is clearly stated on p. 15: "If the biology of