Zinc for the common cold? Not for me


Former Executive Editor, Harvard Health

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Media channels are atwitter with the news that zinc can beat the common cold. CBS News, the L.A. 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 [italics mine], before making a general recommendation for zinc in treatment of the common cold.”

Not exactly a ringing endorsement.

Zinc isn’t something to mess around with. Two years ago, the FDA warned everyone to stop using zinc-containing nasal sprays to fight colds because these sprays had been linked to more than 100 cases of loss of smell. The Institute of Medicine set the tolerable upper limit for zinc at 40 milligrams a day for adults, less for teens and children. The tolerable upper limit is the highest daily intake “likely to pose no risk of adverse health effects for almost all individuals.” If you follow the directions on zinc-based cold remedies, you’ll get more than the tolerable upper limit.

The glowing media reports are sure to spark the next cold rush as supplement makers crank up their zinc output. I’m going to ignore it. I don’t like the taste of zinc lozenges, and don’t think it’s worth sucking on them for several day to knock a day off a cold.

At the first sign of a cold, I’m headed to the kitchen to make chicken noodle soup.


  1. Elizabeth Go

    I’m totally agree with you. “At the first sign of a cold, I’m headed to the kitchen to make chicken noodle soup”. Yes, indeed it works for me. Thanks a lot!

  2. Susan Childs

    Taking traditional chinese medicines are also good for the common cold. This form of medication is more holisticas most of the ingredients are natural herbs. Precaution must be taken to ensure its prescribed by a licenced chinese medicine doctor only.
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  3. Anonymous

    Maintaining health is better than cure. Enter a grocery that also can function as a drug / can prevent the arrival of the disease, such as vegetable soup that contains lots of vitamins, which is useful to keep in shape.

  4. Graeme Creed

    I have been taking a zinc tablet with breakfast for over 30 years. I am now 64 and have only taken three sick days from work in 23 years.
    Zinc builds up the immune system over years, not just when you have a cold. Zinc also assits with healthy skin and aids healing.

  5. Nev Smith

    Agreed on getting zinc from food rather than pills but must say that my aunt has been using the lozenges for colds and it seems to work for her also!
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  6. Paul

    I’ve been taking zinc preparations at the first sign of a cold for six or seven years and have found that they work for me. I’ve had no problems with nausea, cold sores, etc. The editor’s note strikes me as prissy to the point of near hysteria over the possibility that someone, somewhere might experience a minor side effect. Yes, several dozen people apparently lost their sense of smell from using Zicam nasal gel (which I used dozens of times without adverse effect), and that’s certainly serious, but (1) that was a tiny subset of Zicam users; (2) the product is no longer on the market; (3) millions of people have been taking zinc lozenges for twenty years without serious reported side effects; and (4) there’s no evidence to suggest that sucking on a zinc lozenge has the possibility of causing loss of the sense of smell.

  7. Carlsbad

    Zinc absolutely works for me. At the first sign of cold, tingling sensation in the back of throat or nose, I take Redoxon Effervescent(Zinc 10mg + Vitamin 1000mg) and without fail, the symptoms go away in quickly, usually three or four tablets would do the trick.

    I moved from NY to Singapore and was suffering lots of skin infections and colds. My housekeeper in Singapore taught me the trick of Zinc and Vitamin C. I was skeptical at first, but decided to give it a try. Ever since then I had no more incidence of skin infection and I can’t remember the last time I had a full blown cold. I wouldn’t take zinc lozenge because most of them taste so bad and wouldn’t use intranasal spray and risk losing sense of smell because I love food and 90% of flavor comes from the nose.

    For the non-believers of zinc, good luck to you.

  8. TimFolds

    We can speculate all we want, but the fact of the matter is that ever since I started taking zinc lozenges, I’ve never had a cold like the kinds I used to get before discovering zinc lozenges. It’s been seven years now. I keep a sealed bag of lozenges on-hand. As soon as I feel post nasal drip, I start taking them. As advertised, the duration and severity are, at minimum, cut in half. They work very, very well!

  9. bjb321

    Didn’t anyone ever hear of getting zinc from food? That’s the way to go, instead of some pill or lozenge. So you might want to put a couple of oysters in your chicken noodle soup 🙂

  10. CurrentMedicine.TV

    We agree that this Cochrane meta-analysis received far too much media attention with unsafe consequences. National coverage will lead to millions of people taking a dangerous additive in hopes of stopping a cold. Far more convincing data are required before the public can be told that zinc has any beneficial effect. We do know that intranasal zinc can damage the sensory nerves of smell.


  11. Helen Hoart

    I used to take zinc lozenges when I felt a cold coming on. But I stopped for two reasons. As reported in your blog, the zinc caused nausea. But I also noticed I always developed a cold sore when taking zinc. The zinc did seem to shorten the cold by a day but the cold sore stayed around forever, it seemed, so now no zinc for me. I’d rather deal with a cold than an upset stomach and a nasty cold sore.

  12. J Gottlieb

    My husband (71) and I (65) have been taking zinc (the mineral tablets, not the lozenges) for years at first signs of a cold. Sorry to disappoint you but for us, it totally works. We may still get a cold, but not nearly as severe….it seems to run its course much more quickly if at all. The tablets are easily purchases in any pharmacy (we once needed them while vacationing in Spain) and are under $5.00 for a bottle.

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