The attitudes of the general British population towards Muslims changed post 2001, and this change led to a significant increase in Anti-Muslim discrimination. We use this exogenous attitude change to estimate the causal impact of increased discrimination on a range of objective and subjective health outcomes. The difference-in-differences estimates indicate that discrimination worsens blood pressure, cholesterol, BMI and self-assessed general health. Thus, discrimination is a potentially important determinant of the large racial and ethnic health gaps observed in many countries. We also investigate the pathways through which discrimination impacts upon health, and find that discrimination has a negative effect on employment, perceived social support, and health-producing behaviours. Crucially, our results hold for different control groups and model specifications.