mineral · for frequent colds
Zinc
The mineral itself. Which salt you take changes how much reaches you and what it has been tested for — the cold-lozenge trials used gluconate and acetate, the wound-healing trials used sulfate.
How strong is the research?
A Cochrane review pooled 34 trials in over 8,500 people. Zinc started after a cold begins may shorten it by about two days. The trials disagreed a lot, so that finding is rated low-certainty. Zinc taken to stop colds made little or no difference.
2 papers read, 1 supporting, 1 against.
Tested as: Not one form. Lozenges were used in 17 of 34 studies, as zinc gluconate (9 studies, 45-276 mg/day, 4.5-21 days), zinc acetate (5 studies) or zinc orotate; the rest used capsules, dissolved powders, tablets, syrups or intranasal zinc. Trials combining zinc with other vitamins, minerals or herbs were excluded, so this is zinc alone.
Who was studied: Healthy adults in 22 studies and children in 12, mostly in the USA. The prevention groups were followed for five to eighteen months.
We found 2 studies on this. We have not finished reading them yet, so we are not ready to say either way.
How much to take
45–276 mg