Between 1830 and 1860 the United States experienced rapid economic growth but declining stature and rising mortality. Debate has centered on whether the American diet deteriorated in the mid-nineteenth century. Employing census and muster records, this article tests the hypotheses that adult height was positively correlated with local production of nutrients in early childhood and negatively correlated with local mortality conditions, urbanization, proximity to transport, and population mobility. Results indicate that antebellum economic growth was accompanied by an increasing nationalization and internationalization of the disease environment, which affected the health and longevity of the population.This article is based on two earlier papers presented at the conference “The Biological Standard of Living and Economic Development: Nutrition, Health, and Well-Being in Historical Perspective,” held at the University of Munich, Munich, Germany, 18–21 January 1997. They have been published in The Biological Standard of Living in Comparative Perspective edited by John Komlos and Jörg Baten (Stuttgart: Franz Steiner Verlag, 1998), pp. 155–80 and 190–207. This research was funded in part by the National Institute of Aging (AG 10120) and by the National Science Foundation (#SBR-9408525). The authors wish to thank Brian A'Hearn, Markus Heintel, and Robert Fogel for data and Jörg Baten, Timothy Cuff, Richard Easterlin, Stanley Engerman, John Komlos, John Murray, Richard Steckel, Robert Whaples, and participants at the Economic History Seminar at the University of California at Berkeley, the Economics Seminar at the College of William and Mary, the NBER Summer Institute, and the Social Science Colloquium at Colgate University for valuable comments and suggestions on earlier versions. In addition two anonymous referees provided very useful suggestions. The late Robert Gallman also provided valuable comments at an early stage of the project. Part of this research was conducted by Craig while he was a German Marshall Fund Fellow at the Seminar fuer Wirtschaftsgeschichte at the University of Munich.