In Denmark scientists at Chromaviso are artificially recreating the changing patterns of natural light, from the blue glow of a morning sunrise, to the bright intensity of midday sun, and finally ending with a warm evening hue. These changes in light throughout the day support our circadian rhythm which affects every cell in our body.

Javid Abdelmoneim travels to Copenhagen to see how recreating natural light in care homes can have a dramatic impact on a patient's wellbeing, and goes to meet Dr Andres West at Rigshospitalet where circadian rhythm lighting was installed in a stroke unit to study the neurological benefits for patients.