“I like tea, I like coffee, but I want to sleep at night. What to do?”
The dilemma of many tea drinkers. 

Tea vendors do often provide contradictory information about theine content in tea and the web does not really help either. Let’s find out the truth about a topic that, indeed, is unclear and complex.

Coffee, black tea, green tea: Will I sleep tonight? 

Caffeine: popular misconceptions

First of all let’s get rid of two misleading popular beliefs. Theine is not lighter than caffeine. Already in the 19th century, scientists discovered that theine and caffeine are exactly the same molecule. So it doesn’t matter if you drink tea or coffee, your body will always absorb caffeine. However quantity and the absorption rate can differ substantially.

Theine is identical to caffeine.

Black tea has no more caffeine than green tea… and green tea has no more caffeine than black tea. A contradiction? Not really. The kind of tea (white, black, green…) is determined by the processing, not by the nature of the leaves. For example in Qimen County (Anhui, China), the tea farmers produce Qimen Hong Cha—Keemun, a famous black tea­—and Huangshan Maofeng—a green tea—using the same tea plants. So a green tea can be rich or poor in caffeine; and the same is valid for black tea.

The kind of tea (green, black, white…) is no indication for caffeine content.