And don't expect any help from supplements, like Vitamin D. Vitamin D struck out in the latest study on whether it can help prevent or shorten the common cold.
Researchers found that increasing Vitamin D levels doesn't provide any additional protection against colds.
Although the vitamin is thought to play a key role in immune function, the new study suggests, as a supplement, it's powerless to fight off respiratory infections, even in high doses.
The study was published this week in the Journal of the American Medical Association.
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