ZINC AND THE COMMON COLD

Report #7286

Millions of North Americans take zinc lozenges to treat their colds. A study in the November issue of the Archives of Internal Medicine shows that they neither shorten the cold nor lessen its symptoms.

Of the six controlled studies in the last 15 years, three showed some lessening of symptoms and three found no benefit. When the authors combined the results of the six studies, they found no benefit from the zinc lozenges. They report that it is impossible to do double blind studies because zinc lozenges have a very distinct metallic taste, causing many people taking zinc to drop out of the study. Those who remained in the studies noticed the distinctly metallic taste and may have felt that they are given the test drug and were supposed to feel better. On the other side, the three studies showing no benefit were criticized for using low doses or different ineffective forms of zinc.

In 1849, an article in the British Medical Journal recommended treating a cold by nailing a hat on the wall and going to bed and drinking spirits until you see two hats. One hundred and fifty years later, we don't have a much more effective treatment.

By Gabe Mirkin, M.D., for CBS Radio News