In most countries, females live several years longer than males. Many biological and behavioral reasons have been presented in the scientific literature to explain this “female advantage.” A cross-sectional regression study, using 45 explanatory variables and data collected from 169 countries, provides support to the behavioral hypothesis. Four variables, unrelated to biological sex differences, explain over 61% of the variability of the life expectancy differential. One variable (the number of persons per physician) summarizes the degree of economic development of a country. The three other selected variables (the fertility rate, the percentage of Hindus and Buddhists, and Europeans countries of the former Soviet Union) are social/cultural/religious variables. This conclusion is slightly weakened when the presence of spatial autocorrelation in the data is specifically acknowledged.