When we can’t prevent a cold through healthy living, we can reduce its length and severity. A new meta-analysis of cold research has found significant relief via early use of zinc lozenges and tablets, reducing both symptom severity and duration. Learn more about the new study at Reducing Cold Symptoms.
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Additional research suggesting benefits from zinc lozenges http://www.medpagetoday.com/infectiousdisease/uritheflu/32546#
Looks like zinc is stronger than Vitamin D, for preventing colds anyway http://www.usatoday.com/story/news/health/2012/10/03/vitamin-d-colds-teens-drink-drive/1609891/