Tea certainly contains a surprising amount of caffeine and yet is not generally considered as a stimulant in the same way that coffee is. Some researchers think that this maybe because tea contains something else – in effect cancelling out the caffeine.
The mystery ingredient in tea is now thought to be an amino acid called L-Theanine. Whilst it is not unique to tea, the tea plant seems a particularly rich source. When L-Theanine has been given to people in clinical studies many of the positive effects of tea can be reproduced.
LAMBERTS L-Theanine is the purest form available and is the one used in clinical studies. Our L-Theanine is painstakingly produced by a process of fermentation. We do not use L-Theanine extracted from tea as this contains a high proportion of D-Theanine which is not believed to be as active as the L-Theanine form.