HEALTH

People have a biological clock, which is what tells the body when it's supposed to be up and about and when it is supposed to wind down for sleep. 

One thing that sends a powerful signal to your biological clock is light. Being exposed to natural light first thing in the morning signals the hormones in the body to sep up for the day's activities. 

This means that, many hours later, when it comes to the evening, the body is expecting to wind down for sleep. 

If you aren't getting sunlight in the morning, or, if you are exposed to lots of light late in the evening, your biological clock can get a bit confused and make it harder to wind down for sleep, and harder to wake up in the morning. 

Simply getting enough light early in the day and limiting light - even from screens - later in the day can make a big difference to your sleep.