A Trial of Vitamin D and Health Advice for the Prevention of Upper Respiratory Tract Infections

The specific objectives of this investigation are to assess the effectiveness of daily gargling and vitamin D supplementation as preventative measures against incident upper respiratory tract infection (URTI) in students attending McMaster University. Investigators hypothesize that 1. Vitamin D3 supplementation will decrease the incidence of symptomatic upper respiratory tract infections in university students 2. Gargling will decrease the incidence of symptomatic upper respiratory tract infections in university students.