The American Center for Disease Control (CDC) has recently announced that we do not sleep enough nowadays as a species, qualifying lack of sleep as an epidemic. And as of now, we know one of the reasons for this phenomenon. As surprising as it may sound, we actually are not getting enough darkness. Yup, not sunlight, as you typically hear, but darkness.
Light is the main factor in regulating our sleep patterns.
Our body knows to prepare for shutdown and go to sleep when it gets dark and to wake up and prepare for a new day when there’s light. As modern life has deeply disrupted the routine of this cycle, science has shown that this troubled rhythm can lead to obesity, diabetes and even cancer.
In fact, darkness has certain effects on our body that help us have a good night’s sleep.
- For instance, a certain hormone called Leptin is multiplied in darkness. This hormone controls our feeling of hunger, meaning that high levels of leptin can prevent us from feeling hungry at night. This can be explained by the fact that foraging at night might have been dangerous for our ancestors and therefore feeling hunger may not be beneficial.
- But not all kinds of light are necessarily harmful. Science has in recent decades decrypted the way our eyes perceive light. We have found out that the sun for example has its regulatory effect on our sleep cycle because of all the blue light it contains. Blue light has a big impact on our melatonin, high levels of which tell our body that it’s daytime. The problem now is that we are surrounded by multiple sources of blue light including our phones, tablets and computers. Meaning that the use of these devices at night can actually hurt our sleep.
On the other hand, some other sources of light are not that harmful, and some not at all. Campfire and candles are one of those that do not affect our sleep and same goes for traditional light bulbs and lanterns.