Tuberculosis Treatment Outcomes in Tanzania: A Systematic Review of interventional and operational studies

Background Tuberculosis (TB) remains a leading cause of morbidity and mortality worldwide, with Tanzania being among the high-burden countries. Malnutrition is both a risk factor for TB and a barrier to recovery, yet evidence on the effectiveness of nutritional interventions in improving treatment outcomes remains fragmented. This systematic review synthesized available evidence on the role of nutritional support in enhancing TB outcomes in Tanzania and comparable sub-Saharan African settings. Methods : We conducted a systematic review using PRISMA 2020 guidelines. We searched PubMed, Embase, Scopus, Web of Science, CINAHL, Cochrane Library, and African Journals Online (AJOL) for studies published between 2000 and June 2025. Grey literature from WHO, government reports, and conference proceedings were included. Search strategies combined MeSH terms and keywords related to tuberculosis, nutrition, malnutrition, dietary supplements, Tanzania, and Africa. No language restrictions were applied provided such studies were in the study scope. Two reviewers independently screened records, with disagreements resolved by a third reviewer. Eligible studies included randomized controlled trials, quasi-experimental, cohort, and cross-sectional designs assessing nutritional interventions (macronutrients, micronutrients, food support, or counselling) and reporting TB outcomes (treatment success, cure, mortality, adherence, weight/BMI gain, or quality of life). Risk of bias was assessed using ROB 2.0, ROBINS-I, or JBI tools. Data were extracted with standardized forms and synthesized narratively; effect measures were pooled using random-effects meta-analysis where possible. Results: Eighteen studies involving about 5,007 participants met inclusion criteria. Most reported positive associations between nutritional interventions and improved outcomes, including higher treatment completion, greater weight gain, and reduced mortality. Macronutrient and food-based interventions showed consistent benefits, while effects of micronutrient supplementation were mixed. Operational studies highlighted challenges of implementation and sustainability in resource-limited contexts. Conclusions : This review demonstrates that nutritional support enhances TB treatment outcomes in Tanzania and related settings. Evidence indicates that food-based and macronutrient interventions improve weight gain, adherence, and treatment success, while revealing persistent gaps in evidence for micronutrients and program sustainability. Findings provide timely guidance for policy, supporting the integration of nutritional interventions into Tanzania’s National TB Program and informing broader One Health nutrition strategies.