Cochrane · systematic review · CD014914
Zinc for prevention and treatment of the common cold
Nault, D, Machingo, TA, Shipper, AG, et al. · Cochrane Database of Systematic Reviews · 2024 · Cochrane Library
Acute Respiratory InfectionsAMSTAR 2: not assessed
SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.
Questions
12
current version
GRADE rated
11
No studies
1
Included studies
NR
No studies 1 · 8.3%Ungraded 0 · 0%Very low 3 · 25%Low 6 · 50%Moderate 2 · 16.7%High 0 · 0%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Questions and results
Zinc compared to placebo for prevention of the common cold
Population: adults and children without colds
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Proportion of participants developing a cold Duration of Zinc vs placebo | no estimate extracted | 9 studies · 1449 participants | Low Downgraded: risk of bias |
Mean number of colds developed Duration of Zinc vs placebo | no estimate extracted | 2 studies · 1284 participants | Low Downgraded: risk of bias, inconsistency |
Mean duration of colds in days Duration of Zinc vs placebo | no estimate extracted | 3 studies · 740 participants | Moderate Downgraded: inconsistency |
Standardised mean global symptom severity Duration of Zinc vs placebo | no estimate extracted | 2 studies · 101 participants | Low Downgraded: risk of bias, imprecision |
Risk of adverse events, including those that may be due to zinc supplements Duration of Zinc vs placebo | no estimate extracted | 7 studies · 1517 participants | Very low Downgraded: risk of bias, imprecision |
Risk of serious adverse events, including those that may be complications of the common cold Duration of Zinc vs placebo | no estimate extracted | 3 studies · 1563 participants | Low Downgraded: imprecision |
Zinc compared to placebo for treatment of the common cold
Population: adults and children with colds and/or upper respiratory infections
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Mean duration of colds in days Duration of Zinc vs placebo | no estimate extracted | 8 studies · 972 participants | Low Downgraded: risk of bias, inconsistency |
Risk of continuing colds at study end Duration of Zinc vs placebo | no estimate extracted | 5 studies · 357 participants | Very low Downgraded: risk of bias, inconsistency |
Standardised mean global symptom severity Duration of Zinc vs placebo | no estimate extracted | 2 studies · 261 participants | Very low Downgraded: risk of bias, inconsistency |
Proportion with improved global symptom severity Duration of Zinc vs placebo | no estimate extracted | 1 study · 114 participants | Low Downgraded: risk of bias, imprecision |
Risk of adverse events, including those that may be due to zinc supplements Duration of Zinc vs placebo | no estimate extracted | 16 studies · 2084 participants | Moderate Downgraded: risk of bias |
Risk of serious adverse events, including those that may be complications of the common cold Zinc vs placebo | no estimate extracted | NR | No studies |