Media channels are a-twitter with the news that zinc can beat the common cold. CBS News, the LA Times, the Huffington Post, and hundreds of others are treating a quiet research report as big news that will have a life-changing effect. After reading the report and doing a little digging into the dark side of zinc, I’m not rushing out to stock up on zinc lozenges or syrup.
The latest hubbub about zinc was sparked by a report from the Cochrane Collaboration. This global network of scientists, patients, and others evaluates the evidence on hundreds of different treatments. In the latest review, on zinc for the common cold, researchers Meenu Singh and Rashmi R. Das pooled the results of 13 studies that tested zinc for treating colds. By their analysis, taking zinc within 24 hours of first noticing the signs of a cold could shorten the cold by one day. They also found that taking zinc made colds a bit less severe.
Sounds good so far. But instead of saying, “Hey, take zinc if you have a cold,” the researchers concluded like this:
“People taking zinc lozenges (not syrup or tablet form) are more likely to experience adverse events, including bad taste and nausea. As there are no studies in participants in whom common cold symptoms might be troublesome (for example, those with underlying chronic illness, immunodeficiency, asthma, etc.), the use of zinc currently cannot be recommended for them. Given the variability in the populations studied (no studies from low- or middle-income countries), dose, formulation and duration of zinc used in the included studies, more research is needed to address these variabilities and determine the optimal duration of treatment as well as the dosage and formulations of zinc that will produce clinical benefits without increasing adverse effects [bold is mine], before making a general recommendation for zinc in treatment of the common cold.”
Not exactly a ringing endorsement. Read more »
*This blog post was originally published at Harvard Health Blog*