The dethronement of income as a cause of health: an essay

Abstract

Income, whether of nations, groups or individuals, appears in many analyses to have a strong relation to health status and even to be the principal explanatory variable for health differences. Poor people tend to be sicker than average, and sick people tend also to be poorer than average. Of course, income is needed to buy the goods and services that contribute to protecting and improving health, but its importance has been overstated. Cross-sectional relations that ignore history exaggerate how much income matters for health. Income is "dethroned" as the king of explanations by four lines of evidence: (1) distribution matters more than totals or averages, and the distribution of financial protection through insurance, rather than the distribution of income, is particularly crucial; (2) historically, income growth by itself contributed little to health improvements; (3) it matters more, how rapidly and thoroughly people and nations adopt sound health interventions; and (4) some recent changes in lifestyle (diet and physical activity) that accompany income growth actually worsen health. These causes are especially relevant for infant and child health, somewhat less so for maternal health. The less important income is, the easier it is to improve health; so it is good news that countries and people need to escape from poverty, but they don't have to be rich to be healthy.