Published in The Hindu on September 4, 2012

Scientists have found that vitamin D supplementation in tuberculosis patients who are on medication can clear the Mycobacterium tuberculosis — the bacterium that causes TB — quickly and hasten recovery.

“Vitamin D supplementation … has a potential role in the prevention and treatment of [TB] infection,” notes a study published on Tuesday in the Proceedings of the National Academy of Sciences ( PNAS ). “Our findings suggest a potential role for vitamin D supplementation in the treatment of pulmonary infections.”

Vitamin D was used to treat TB before the advent of antibiotics. Its efficacy in enhancing immunity in healthy individuals who are in close contact with TB patients is also well known.

In the PNAS study, the scientists conducted a randomised trial on 95 patients with pulmonary TB and who were already on TB medication. Fifty-one patients did not get vitamin D supplementation (placebo group) and the remaining 44 got the supplementation in addition to the medication (intervention group).

What they found was truly significant — the average time taken for the bacterium to become undetectable under a microscope was 23 days in the intervention group compared with 36 days in the placebo group. In the case of culture studies, the average time for the intervention group to get rid of the bacterium was 35 days compared with 46.5 days in the placebo group.

Parameters

If the 17 parameters they studied were “significantly affected” by antibiotics alone, the effects were more pronounced in the group that received vitamin D supplementation.

For instance, the group that received the supplementation showed an increase in lymphocyte count. Lymphocytes are part of the immune system and make up 45 to 50 per cent of the white blood cells in healthy people. But the numbers reduce to about 20 to 25 per cent in those with pulmonary TB.