The authors examined the relation between dietary and supplemental micronutrient intake and subsequent mortality among 281 human immunodeficiency type 1 (HIV-1)-infected participants at the Baltimore, Maryland/Washington, DC, site of the Multicenter Acquired Immunodeficiency Syndrome Cohort Study. Subjects completed a semiquantitative food frequency questionnaire at their baseline visit in 1984. Levels of daily micronutrient intake were examined in relation to subsequent mortality over the 8-year follow-up period by using multivariate Cox models, adjusting for age, symptoms, CD4+ count, energy intake, and treatment. The highest quartile of intake for each B-group vitamin was independently associated with improved survival: B1 (relative hazard (RH) = 0.60, 95% confidence interval (CI) 0.38-0.95), B2 (RH = 0.59, 95% CI 0.38-0.93), B6 (RH = 0.45, 95% CI 0.28-0.73), and niacin (RH = 0.57, 95% CI 0.36-0.91). In a final model, the third quartile of beta-carotene intake (RH = 0.60, 95% CI 0.37-0.98) was associated with improved survival, while increasing intakes of zinc were associated with poorer survival. Intakes of B6 supplements at more than twice the recommended dietary allowance were associated with improved survival (RH = 0.60, 95% CI 0.39-0.93), while intakes of B1 and B2 supplements at levels greater than five times the recommended dietary allowance were associated with improved survival (B1: RH = 0.61, 95% CI 0.38-0.98; B2:RH = 0.60, 95% CI 0.37-0.97). Any intake of zinc supplements, however, was associated with poorer survival (RH = 1.49, 95% CI 1.02-2.18). These data support the performance of clinical trials to assess the effects of B-group vitamin supplements on HIV-1-related survival. Further studies are needed to determine the optimal level of zinc intake in HIV-1-infected individuals.