HIV infection causes immune activation that leads to oxidative damage. Proinflammatory cytokines may promote such damage and the regulatory cytokine IL-10 may protect against such damage. To examine the relation of these cytokines to oxidative damage, 67 cases of oxidative damage and 67 matched controls were selected from the reaching for excellence in adolescent health (REACH) study. Subjects were young (15-23 years), largely female (76%), HIV-positive (73%) and black (69%). Proinflammatory cytokines were not significantly associated with oxidative damage but plasma IL-10 had a significant, negative association with oxidative damage. This finding is consistent with a protective role for IL-10 in diminishing oxidative damage during immune activation. © 2005 Taylor & Francis Group Ltd.