Aibana O, Huang CC, Aboud S, et al. - In this study performed in Lima, Peru, researchers examined how tuberculosis (TB) disease risk could be influenced by baseline vitamins D levels in a prospective cohort including 6,751 HIV-negative household contacts of TB patients. In people at high risk for TB disease, they measured serum 25–(OH)D levels. These individuals were observed for the development of TB over 1 year. Cases were household contacts with TB development at least 15 days following enrollment of the index patient. Among contacts who did not develop TB disease, four controls were randomly selected for each case, matching on gender and year of age. Individual-level data were pooled from seven earlier published prospective investigations performed worldwide and from the Lima cohort. According to the findings, TB disease risk was predicted by vitamin D in a dose-dependent manner, and HIV-positive people with severe vitamin D deficiency exhibited the highest risk of TB disease. The likely role of vitamin D supplementation on decreasing TB disease risk requires evaluation in randomized control trials.