People from some overseas countries are up to four times more likely to develop tuberculosis (TB) in the UK than they would in the country they came from, says a recent research. The researchers believe that the move away from a sunny climate to cloudy and grey skies of the UK is to blame. They say the lack of sunshine results in vitamin D deficiency, which reduces the ability of the body's immune system to keep TB at bay. The research, which was based on Somalian and Gujrati Indian migrants, has found a deficiency of vitamin D in both communities as well as high incidence of TB.