Your body has an internal clock called your “circadian rhythm.” Primarily influenced by light exposure, it signals to your body when it is time to sleep by altering various hormones (e.g. cortisol and melatonin).

To optimise the secretion of these hormones, you must follow the light exposure rhythm in which humans have evolved. This means exposing yourself to bright light during the day while minimising light exposure at night. This does wonders for your sleep.

In the daytime, it is best to expose yourself to the light of the sun for at least 30 minutes a day. If that is not possible, consider investing in a daylight lamp (also known as a full-spectrum lamp). When strong enough (2,500 lux or more), it mimics sunlight and improves sleep.

A 10,000 lux lamp is ideal and only requires 20 to 30 minutes of exposure to be effective. However, 2,500 lux can be as effective if you are exposed to it for two hours. Just have the light on throughout the day or upon awakening to enhance your sleep at night.

At night, limit (blue) light exposure because it prevents the secretion of the sleep hormone melatonin.  Do so by sleeping in a pitch-dark room, the “I can not see my pillow” kind of dark. You can purchase black-out curtains to create total darkness in your bedroom at night.

If you want to watch TV or use the computer at night, invest in a pair of blue-light blocking glasses. Since blue light is the main circadian disruptor at night, these glasses increase melatonin secretion and boost sleep quality.