The ingredients in herbal teas may be considered food additives under the FDCA, especially when manufacturers combine many different herbs to make the tea available to affect many different health conditions.
Herbal teas run the risk of being considered adulterated because they use herbs that are not GRAS. Also it may be difficult for manufacturers to get GRAS approval for herbs they would like to use because the are lacking in scientific evidence for that particular use of the herb, or because the FDA may consider the herb to be unsafe. | 
