Vitamin D is in the news a lot but, according to a leading researcher, there’s good reason for it. The website, Medscape, interviewed Dr. Cedric Garland, a professor at the University of California San Diego, who has examined the association between vitamin D and disease. Dr. Garland’s research has shown that the risk of all-cause mortality (the risk of dying from any cause) goes up as vitamin D blood levels drop below 30 ng/ml, which is consistent with other scientific work on vitamin D. According to Dr. Garland, every person should aim to have levels above 30 ng/ml. Statistics show that two-thirds of the US population have levels below 30 ng/ml, and therefore need supplementation. If you’re looking to have your levels tested, Dr. Garland notes that March is the best time of year to do so, as this is when vitamin D levels are at their lowest.