L-Theanine is a fascinating amino acid that is present in normal tea and is believed to be responsible for that unique ‘nice cup of tea’ feeling. Supplements of L-Theanine are now very popular, particularly in the USA, and Lamberts L-Theanine is one of the leading brands in the UK.

Unlike most supplements that need to be part of a regime for several weeks before any effect may be noted, with L-Theanine there is a response within the first few hours of use.