This paper measures inequality of opportunity in adult health in Colombia using the 2010 Living Standards and Social Mobility Survey, a rich dataset that provides unique information about individual childhood circumstances in that country. Dissimilarity and Gini-opportunity indexes are calculated to provide different measures of inequality of opportunity using a self-reported variable for health status. The Shapley-value decomposition is then used to estimate the contribution of early-life circumstances such as parental background, region of origin and ethnicity to inequality of opportunity. The findings suggest that 8 % to 10 % of the circumstance-driven opportunities distinctively enjoyed by those who are healthier should be redistributed or otherwise compensated in order to achieve equality of opportunity. Differences in household socio-economic status during childhood and parental educational attainment appear to be the most salient dimensions of inequality of opportunity in adult health.