Does tea have caffeine? Absolutely!

Every tea brewed with leaves from the tea plant (Camellia sinensis) always contains caffeine, but the amount of caffeine in tea depends on much more than just the type of tea you choose.

The real science behind tea and caffeine challenges the myth that caffeine content is determined by tea type, and that black tea always has more caffeine than green tea.

Around the world, we drink tea for both its taste and for how it makes us feel. In tea, caffeine works together with L-theanine, EGCG and more for a nuanced and unique effect unlike any other beverage in the world.

That’s why understanding a tea’s caffeine level is just one of the first steps to understanding how tea affects us. To really get a full picture of how caffeine works in tea, we first need to know how a tea was farmed, when it was picked, and how you’ll brew it.

"Every tea brewed with leaves from the tea plant always contains caffeine."

Does all tea have caffeine?

Caffeine is nature’s most widely-consumed stimulant, increasing blood flow, heart rate, and general alertness. The tea plant (Camellia sinensis, L. Kuntze) naturally produces caffeine as a defense against insects, and tea’s stimulant effect was used even in ancient times as a meditation aid for monks' early morning rituals. 

Until recently, we thought caffeine alone was responsible for the alertness and clarity you get drinking tea. Now, we know brewed tea contains a complex combination of caffeine, the related stimulants theobromine and theophylline, and the counterbalancing effect from L-theanine and antioxidants. Caffeine alone can cause a jittery feeling, but in tea, the jitters are usually missing thanks to this complex balance. 

Take note!  Measuring caffeine content in tea (or any brewed beverage) requires specialized lab equipment and serious expertise. Because the caffeine content of tea can vary so widely - from tea to tea and from season to season - it is difficult to estimate the specific mg per cup of any specific harvest.

Take any advertised caffeine content of loose leaf tea with a grain of salt. These are often just general estimates that have not been confirmed by food scientists.