title: Vitamin D supplementation effective in preventing acute respiratory tract infections.
abstract: Studies have consistently shown low levels of vitamin D make people more susceptible to respiratory infections. Acute respiratory infections are a major cause of ill health and mortality. Observational studies have shown that people with low levels of 25-hydroxyvitamin D, the major circulating vitamin D metabolite, are susceptible to respiratory infection.
mesh_terms: D000208:Acute Disease; D019587:Dietary Supplements; D004311:Double-Blind Method; D006801:Humans; D010919:Placebos; D016032:Randomized Controlled Trials as Topic; D012141:Respiratory Tract Infections / Q000517:prevention & control*; D014807:Vitamin D / Q000008:administration & dosage*
chemical_list: D010919:Placebos; D014807:Vitamin D