The author F Scott Fitzgerald was right when he commented: “The worst thing in the world is to try to sleep and not to.” Anyone who has tossed and turned all night and then had to face work the next day will relate to this statement. And if restless nights are a regular occurrence, the effect of this lack of sleep can quickly take its toll.

We spend around a third of our lives asleep and far from being a passive, dormant process, doctors now know that sleep is a very active phase, particularly for our brains. Experts are beginning to realise that sleep has a major impact on many aspects of our lives, from how we respond to stress to the functioning of our immune systems.

Here, we take a closer look at sleep and what happens when our sleep patterns become disrupted; the common causes of insomnia; self-care tips you can recommend; and the role of OTC medication in relieving temporary sleep disturbances.