After the volunteers stopped drinking the tea at the end of the two weeks, levels of glycine and hippurate stayed elevated for up to a further two weeks, which suggests the effects may be long-lasting.

BBC: Camomile tea produced changes in the body

Mr Berezovsky was a close friend of murdered Russian emigre and former KGB officer Alexander Litvinenko, who died in 2006 after he was poisoned with the radioactive material polonium-210 while drinking tea at a London meeting.

BBC: UK

Born in Portland, Mr. Smith said that his strongest tea memory is drinking sweetened Red Rose at his grandmother's after school, the whole house filled with the aroma.

WSJ: Steven Smith, Teamaker: The All-Star Alchemist of Top-Shelf Tea | Creating