Although there is no cure for the common cold, doctors believe that vitamins can help prevent them. Many doctors recommend vitamin C to prevent colds, and some doctors suggest that you take large amounts when you begin to get colds symptoms. Yet it is not really known whether vitamin C is truly helpful. When you have a cold, you should also try to protect other people. Cover your mouth and nose with a tissue when you cough or sneeze. Put all your used tissues in a paper bag, and throw away the bag yourself so that no one else will have to touch it. Wash all objects that you touch with very hot water before anyone else uses them. What advice do doctors give about vitamin C? Doctors recommend vitamin C to ______.