In This Issue of Archives of Internal Medicine

I n the era of highly active antiretroviral therapy, diarrhea remains common. Lactose avoidance is often empirically recommended, despite a lack of evidence to support this practice and despite the risk of possible adverse consequences. In this randomized, double-blind, noninferiority crossover trial, moderate ingestion of lactose-containing milk did not worsen diarrhea compared with lactose-free milk in a sample of predominantly gay men. This finding remained consistent when the analysis was limited to the subgroup of lactase-deficient participants. Therefore, avoidance of moderate quantities of milk may not be justified in this population.