Each year, about one billion cases of the common cold affect adults and children in the United States. To boost their defense against cold-related sneezing, sniffling, cough, and congestion, some people turn an herbal remedy known as wild indigo. Available in supplement form, wild indigo is known to contain arabinogalactans, a type of compound that may help stimulate your immune system. Although research on the health effects of wild indigo is limited, some preliminary studies suggest that it may possess immune-enhancing properties. For example, a report published in the journal Advances in Therapy determined that wild indigo may help improve immune function when taken in combination with echinacea and white cedar leaf tips.
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