Traditional plain tea black or green is made from the leaves of the Camellia sinensis plant, which is not related to gluten. The main difference between loose teas and bagged teas is the size of the leaves and glue is used in tea bags which could contain gluten.
When the tea leaves are broken up, those oils can evaporate, leaving a dull and tasteless tea. Typical tea bags are filled with the tiniest pieces of broken leaves, called fannings. Take the time and you can taste the difference in loose tea on sale.
Blue Moon Fine Teas