Background:The results of cross-sectional studies indicate that micronutrient deficiencies are common in patients with tuberculosis. No published data exist on the effect of vitamin A and zinc supplementation on antituberculosis treatment. Objective: Our goal was to investigate whether vitamin A and zinc supplementation increases the efficacy of antituberculosis treatment with respect to clinical response and nutritional status. Design: In this double-blind, placebo-controlled trial, patients with newly diagnosed tuberculosis were divided into 2 groups. One group (n = 40) received 1500 retinol equivalents (5000 IU) vitamin A (as retinyl acetate) and 15 mg Zn (as zinc sulfate) daily for 6 mo (micronutrient group). The second group (n = 40) received a placebo. Both groups received the same antituberculosis treatment recommended by the World Health Organization. Clinical examinations, assessments of micronutrient status, and anthropometric measurements were carried out before and after 2 and 6 mo of antituberculosis treatment. Results: At baseline, 64% of patients had a body mass index (in kg/m 2 ) < 18.5, 32% had plasma retinol concentrations < 0.70 mol/L, and 30% had plasma zinc concentrations < 10.7 mol/L. After antituberculosis treatment, plasma zinc concentrations were not significantly different between groups. Plasma retinol concentrations were significantly higher in the micronutrient group than in the placebo group after 6 mo (P < 0.05). Sputum conversion (P < 0.05) and resolution of X-ray lesion area (P < 0.01) occurred earlier in the micronutrient group. Conclusion: Vitamin A and zinc supplementation improves the effect of tuberculosis medication after 2 mo of antituberculosis treatment and results in earlier sputum smear conversion. Am J Clin Nutr 2002;75:720-7.