News about the importance of vitamin D—the sun—for our health keeps coming in. Now a major research review suggests that people with mild or moderate asthma who take vitamin D halve their risk of serious attacks requiring hospital treatment. The risk of severe attacks fell from 6 to 3 percent in patients who had a vitamin D boost for six months to a year. The supplements cut the frequency of attacks too, with cases needing steroid treatment falling from one per person every two or so years, to one every four years.
