This article examines declining adult human stature in the nineteenth century in three countries: the United States, England, and the Netherlands. While this was not unprecedented, these three relatively important nations did experience a deterioration in the biological standard of living at a time when economic development was proceeding at a goodly pace. England and the Netherlands were among the most urbanized countries in Europe at the time, while the United States was still predominantly rural and agrarian. The essay argues that a confluence of circumstances contributed to the worsening of the physical condition of these populations even while real income per capita was growing. Among the factors involved were rapid urbanization without adequate public health and sanitation; a transport revolution and related commercialization, which brought people and goods into much closer contact; the consequent integration of disease environments, both within and across nations; and a growing dependence of the working populations on wage income along with a probable growing inequality in wealth and income, exacerbating the impact of fluctuations in food prices. Technological change had an impact on these events by lowering the relative prices of industrial goods. While the term Malthusian crisis (i.e., a shortage of subsistence followed by a rise in mortality) seems inappropriate in these cases, a similar process may have been taking place. It suggests that such a crisis may not commence with an increase in mortality but rather with an adjustment of the human organism to new nutritional circumstances.