We exploit changes in minimum legal alcohol purchasing ages in Denmark in order to estimate effects on short- and long-term health-related outcomes, as well as on human capital formation. Using a difference-in-differences approach we bring comprehensive evidence on the effects of three reforms, which affected alcohol availability along different dimensions and margins – 1) establishing an off-premise alcohol purchase age of 15 (1998), 2) raising the off-premise alcohol purchase age to 16 (2004), and 3) increasing the purchase age of beverages exceeding 16.5% in alcohol content from 16 to 18 (2011). Our findings show significant short-term effects on injuries and, although power is lower, indications of substantial effects on alcohol poisonings and intoxications. In the longer term, our results indicate that being able to buy alcohol before age 15 increases injuries and alcohol-related hospitalizations in late teenage years and increases sick days in young adulthood. The effects on educational attainment are insignificant once age-specific time trends are accounted for.