Horizon: How to Sleep Well with Michael Mosley

Sleep is a ritual that unites us all. But why do we do it? Michael Mosley reveals how sleep affects almost every part of our physical and mental wellbeing, from memory and mood to immunity, weight, and fertility. New research and theories are put to the test in experiments never-before shown on TV. And in the UK's biggest-ever sleep survey, discover how sleeping habits vary across age, lifestyle, and location.