High doses of vitamin D do not help prevent tuberculosis, according to the findings of a new study.
In findings published last week in The New England Journal of Medicine, Harvard and Mongolian researchers indicate that not only did vitamin D fail to help ward off tuberculosis, but it also failed to help prevent serious respiratory infections developed from the disease.
The study involved data on 8,800 Mongolian schoolchildren, with researchers focusing on vitamin D supplementation and its link to developing tuberculosis. The children had negative results for Mycobacterium tuberculosis infection, and were randomly assigned to receive a weekly oral dose of either 14,000 IU of vitamin D3, or placebo for three years.
Research indicates vitamin D metabolites support innate immune responses to Mycobacterium tuberculosis. This study focused on whether this could lead to protection from developing tuberculosis.
However, the findings indicate there was little difference in tuberculosis rates among children given Vitamin D, compared to those who were not. The percentage of children with a positive tuberculosis result was 3.6% in the vitamin D group. Similarly, 3.3% of children in the placebo group tested posted for tuberculosis.
Overall, 21 children in the vitamin D group received a tuberculosis diagnosis and 25 children in the placebo group received a tuberculosis diagnosis.
Vitamin D levels among all children at the beginning of the study were less than 20 ng per milliliter. Vitamin D levels at the end of the trail were 31 ng per milliliter in the vitamin D group and 10.7 ng per milliliter in the placebo group.
Furthermore, 29 children in the vitamin D group and 34 in the placebo group were hospitalized for treatment of acute respiratory infection.
“Vitamin D supplementation did not result in a lower risk of tuberculosis infection, tuberculosis disease, or acute respiratory infection than placebo among vitamin D–deficient schoolchildren in Mongolia,” the researchers concluded.
Tuberculosis, also known as TB, is a contagious infection that mainly affects the lungs, but can also affect other organs. If left untreated, it can be life threatening and can block the oxygen in the lungs. The bacteria that causes the disease is easily spread from one person to another through tiny droplets released into the air during coughs and sneezes.
Estimates indicate approximately 1.7 million people worldwide have a latent tuberculosis infection. About 10% of those infections will progress to full tuberculosis in their lifetime.