Vitamin D dose can fight off TB for weeks
A study published in the American Journal of Respiratory and Critical Care Medicine found that a single 2.5mg dose of vitamin D may be enough to boost the immune system to fight TB and similar bacteria for at least six weeks.
Researchers from Queen Mary’s School of Medicine and Dentistry and the Wellcome Trust Centre for Research in Clinical Tropical Medicine at Imperial College London studied about 200 patients who had been exposed to TB.
About two-thirds had latent TB while the rest had been exposed to TB, but had not become infected.
The patients, from London, were in high-risk groups and included migrants and the elderly.
The findings come after a recent outbreak of the disease at two Cork creches, in which 20 people have so far been affected. Since health officials were first notified in mid-March, 17 children and three adults have been diagnosed with TB, the first being a childcare worker who worked at both centres.
The British researchers found that more than 90% of the patients studied were suffering from a vitamin D deficiency, but that a supplement helped the body fight infection by mycobacteria, the family of bacteria that includes TB. The supplement was found to stop reactivation of latent TB in those sufferers.
Dr Adrian Martineau from Imperial College London, who co-ordinated the study, said: “We found that a single large dose of vitamin D was sufficient to enhance a person’s immunity to the bacteria.
“This is very significant given the high levels of vitamin D deficiency in people at the highest risk of TB infection, and shows that a simple, cheap supplement could make a significant impact on the health of people most at risk from the disease.”
Sunlight is the main source of vitamin D, although a diet of oily fish can also provide some of what is required.
However, the amount of sunlight in Britain or Ireland is not enough to provide what most people need, and the elderly do not have the ability to absorb it as well as other people.
Professor Chris Griffiths, from Queen Mary’s School of Medicine and Dentistry, said most TB cases in London arise from people who have already become infected with the bacteria but in whom it lies latent.
“Our results indicate that vitamin D supplementation may prevent reactivation of latent TB. Identifying people with latent TB and providing supplements could be an important strategy for tackling the disease.”
