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Zinc supplementation, particularly in the form of lozenges, can significantly reduce the duration of common cold symptoms and increase the rate of recovery. While some studies suggest that zinc can make colds go away up to three times faster, this effect may vary depending on the formulation, dosage, and individual patient factors. Further research is needed to establish the most effective zinc treatment protocols for the common cold.
The common cold is a prevalent illness that affects millions of people worldwide, leading to significant economic and social burdens. Various treatments have been explored to alleviate the symptoms and reduce the duration of the common cold, with zinc being one of the most studied micronutrients. This article examines whether taking zinc can make colds go away three times faster, based on findings from multiple research studies.
Zinc and Cold Duration
Several studies have investigated the impact of zinc on the duration of common cold symptoms. A systematic review of randomized controlled trials found that zinc supplementation could reduce the duration of colds by approximately 2.25 days when provided singly2. Another meta-analysis of zinc acetate lozenge trials reported that colds were, on average, 40% shorter for the zinc groups compared to placebo groups3. This suggests a significant reduction in cold duration, although not necessarily three times faster.
Rate of Recovery
An individual patient data meta-analysis revealed that patients administered zinc lozenges recovered at a rate 3.1 times faster than those given a placebo3. On the fifth day of treatment, 70% of the zinc-treated patients had recovered compared to only 27% of the placebo group, indicating a substantial increase in the rate of recovery.
Symptom Severity and Incidence
While zinc has been shown to reduce the duration of cold symptoms, its effect on symptom severity is less clear. Some studies have reported a significant reduction in symptom severity scores among zinc-treated patients5, while others found no significant difference1. Additionally, zinc supplementation for at least five months has been associated with a reduced incidence of colds, school absenteeism, and antibiotic prescriptions in children8.
Side Effects and Considerations
Despite the potential benefits, zinc lozenges can cause side effects such as bad taste and nausea1 8. Therefore, the use of zinc should be balanced against these adverse effects. The optimal formulation and dosage of zinc lozenges also require further investigation to maximize benefits while minimizing side effects3 4.
Will taking zinc for colds make it go away 3-times faster?
Brent Bauer, M.D. has answered Uncertain
An expert from Mayo Clinic in Alternative Medicine, Internal Medicine
There’s been a lot of talk about taking zinc for colds ever since a 1984 study showed that zinc supplements kept people from getting as sick. Since then, research has turned up mixed results about zinc and colds.
Recently an analysis of several studies showed that zinc lozenges or syrup reduced the length of a cold by one day, especially when taken within 24 hours of the first signs and symptoms of a cold.
Most colds are caused by a type of virus called rhinovirus, which thrives and multiplies in the nasal passages and throat (upper respiratory system). Zinc may work by preventing the rhinovirus from multiplying. It may also stop the rhinovirus from lodging in the mucous membranes of the throat and nose.
Zinc may be more effective when taken in lozenge or syrup form, which allows the substance to stay in the throat and come in contact with the rhinovirus.
But the recent analysis stopped short of recommending zinc. None of the studies analyzed had enough participants to meet a high standard of proof. Also, the studies used different zinc dosages and preparations (lozenges or syrup) for different lengths of time. As a result, it’s not clear what the effective dose and treatment schedule would be.
Zinc — especially in lozenge form — also has side effects, including nausea or a bad taste in the mouth. Many people who used zinc nasal sprays suffered a permanent loss of smell. For this reason, Mayo Clinic doctors caution against using such sprays.
In addition, large amounts of zinc are toxic and can cause copper deficiency, anemia and damage to the nervous system.
For now, the safest course is to talk to your doctor before considering the use of zinc to prevent or reduce the length of colds.
This answer was re-published from my answer on the Mayo Clinic Blog here.
Will taking zinc for colds make it go away 3-times faster?
Tom Fitzgerald has answered Likely
An expert from University of Michigan in Health, Diabetes
In our studies, zinc lozenges reduces the number of days of cold symptoms by 2 to 3 days. The lozenges were especially designed for the study and are not commercially available. You can read more about it here.
Will taking zinc for colds make it go away 3-times faster?
Harri Hemila has answered Likely
An expert from University of Helsinki in Epidemiology, Nutrition
Three randomized trials with zinc acetate lozenges found that on average the rate of recovery was about 3 times faster in the zinc groups compared with the placebo groups. In addition, two zinc gluconate trials found about 3 times faster recovery in the zinc groups (Source).
Another way to estimate the treatment effect of zinc lozenges on common cold is by the effect on cold duration. On average, zinc acetate and zinc gluconate lozenges shortened the duration of colds by over 30%. (Source 1, 2). Although zinc lozenges are dissolved in the pharyngeal region, their effects on the nasal symptoms are not less than on the symptoms in the pharyngeal region (source).
Although there is strong evidence that properly composed zinc lozenges can increase the rate of recovery from the common cold, the majority of zinc lozenges on the market appear to have either too low doses of zinc or they contain substances that bind zinc ions, such as citric acid. Thus, the results of the randomized trials should not be directly extrapolated to the wide diversity of zinc lozenges on the current market.
We have published a new trial on zinc lozenges in 2020. That study did not find benefit from zinc acetate lozenges. However, low dose of zinc, small size of lozenges and the short 5-day treatment were considered potential explanations for the negative finding. Furthermore, a substantial decrease in the rate of recovery in the zinc participants was seen after the 5-day treatment ended which could be caused by the rebound effect so that the discontinuation of the zinc lozenge treatment had a physiological effect in the harmful direction. Although such a finding is consistent with zinc having a pharmacological effect, it does not support the initiation of zinc treatment. Nevertheless, the new study does not refute eight previous studies that found benefit of zinc lozenges.
Thus, there is strong evidence for the concept that zinc lozenges can be beneficial for treating colds, but the characteristics of zinc lozenges that are clinically efficacious should be evaluated in detail before they can be widely promoted for common cold treatment.
Will taking zinc for colds make it go away 3-times faster?
Divya Ramnath has answered Near Certain
An expert from University of Queensland in Molecular Biology, Hepatology, Infectious diseases
Many metal ions, including Zinc, are toxic to pathogens. This is particularly well-established in the case of diarrhoea, where zinc supplements help manage it.
Will taking zinc for colds make it go away 3-times faster?
Paul Ernsberger has answered Likely
An expert from Case Western Reserve University in Pharmacology, Nutrition, Cardiology, Nephrology, Endocrinology, Obesity
Trials with zinc lozenges are generally positive, but they point more toward prevention than cure. Zinc may bind to the rhinovirus and prevent it from attaching to the cell.