Legal in the UK, Khat is one of many names for a crimson brown plant grown in East Africa and parts of the Arabian Peninsula - and chewed or drunk as a stimulant since the seventh century.
But the plant, which is a major feature of life in Somalia and Yemen, is increasingly the cause of devastating social problems for Somali communities in the UK because of the massive increase in male usage. This week the Home Office have embarked on a study to assess the level of harm caused by khat.
Angela Robson went to investigate and first spoke to Zulekha, a Somali woman living in Sheffield. For more information call the BBC Actionline on 0800 044 044