Higher education (or more years of formal schooling) is widely associated with better health, but the underlying causes of this association are unclear. In this study, we tested our schooling-decision-making model, which posits that formal education fosters intellectual ability, which in turn provides individuals with enduring competencies to support better health-related behaviors. Using data from a field study on formal education in 181 adults in rural Ghana, we examined health-protective behaviors related to HIV/AIDS infection, a critical health issue in Ghana. As expected, individuals with more education practiced more protective health behaviors. Our structural equation modeling analysis showed that cognitive abilities, numeracy, and decision-making abilities increased with exposure to schooling, and that these enhanced abilities (and not HIV/AIDS knowledge) mediated the effects of education on health-protective behavior. Research and policy implications for HIV prevention efforts in sub-Saharan Africa are discussed.