Caffeine in Tea and Coffee
True tea is made from the leaves of an Asian evergreen known as Camellia sinensis. White tea, green tea, oolong tea, and black tea all come from this plant, and all contain caffeine. Our herb teas are made from other, unrelated plants and do not have any caffeine. One exception is Yerba Maté, an herb tea that does contain caffeine.
Researchers believe that in plants, caffeine works as a natural defense system to deter insects and other herbivores with the compound's bitter taste and stimulating qualities. And, not so surprisingly, it's the vulnerable, growing buds and young leaves of tea plants that manufacture the highest amounts of caffeine.
Many factors influence how much caffeine is present in plucked tea leaves. These include the growing region, plant varietal, plant age, leaf age, length of the growing season, field conditions, soil nutrients, rainfall, and stress by pests. Final caffeine content may be further affected during production of the leaves into the finished “style” (white, green, etc.).
How the tea is actually prepared plays an important role in how much caffeine makes it into your cup. Everything, from the amount of tea used to water temperature and brewing time to whether the leaves are steeped loose, in a tea bag, or strainer, becomes a factor. In general, though, more tea, hotter water, and longer steeping all contribute to more caffeine per cup.
Given all of these variables, it really is difficult to answer the question, “How much caffeine is in this tea?” Because we know that caffeine is a concern, we offer these general ranges based on some of our products. Please keep in mind that these numbers reflect varying steeping times and amounts of tea leaves per cup.