According to one study, eating kiwi fruit before bed helps deep sleep. But which other foodstuffs may aid a long and peaceful slumber?

Ahead of World Sleep Day next week – an awareness-raising exercise that should surely be renamed World Sleep Night – there has been increased focus on how much sleep we should be getting (more than we probably are) and how to get it. The event has prompted the strange claim that eating two kiwi fruits before bed leads to better kip – the result of a 2011 study at the Taipei Medical University – to resurface. However, the study was also “supported” by the world’s largest marketer of kiwi fruit, and had just 24 participants. Kiwis do have high levels of serotonin, which is critical to sleep – but what other foods could help?