Background Few studies have analysed the effects of income inequality on health in developing countries, particularly during economic growth, reduction of social disparities and reinforcement of the welfare and healthcare system. We evaluated the association between income inequality and life expectancy in Brazil, including the effect of social and health interventions, in the period 2000–2009.

Methods A panel dataset was created for the 27 Brazilian states over the referred time period. Multivariable linear regressions were performed using fixed-effects estimation with heteroscedasticity and serial correlation robust SEs. Models were fitted for life expectancy as a dependent variable, using the Gini index or a percentile income dispersion ratio as the main independent variable, and for demographic, socioeconomic and healthcare-related determinants as covariates.

Results The Gini index, as the other measure of income inequality, was negatively associated with life expectancy (p<0.05), even after adjustment for all the socioeconomic and health-related covariates. The Family Health Program, the main primary healthcare (PHC) programme of the country, was positively associated with life expectancy (p<0.05).

Conclusions In recent years, effective social policies have enabled Brazil to partially reduce absolute poverty and income inequality, contributing—together with PHC—to decreasing death rates in the population. Reducing income inequality may represent an important step towards improving health and increasing life expectancy, particularly in developing countries where inequalities are high.