Archived notice: This article was published during the early 2020 COVID-19 lockdowns and is no longer maintained as current health guidance. Its original recommendations have been removed because they were not sufficiently sourced for medical use.
For current information about immune-system health, nutrition or supplements, use guidance from a qualified healthcare professional and authoritative public-health sources such as the US Centers for Disease Control and Prevention and the NIH Office of Dietary Supplements.
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