It seems we are in for an early spring. We are already seeing double-digit temperatures and most of the snow is gone. Hopefully, it means that we are heading outside more and getting into the sun. I’ve written several articles on the importance of the sun, but that’s because of just how important it is for our overall health both physically and mentally. Today I want to focus on how the sun and light in general, affect our sleep/wake cycle.
I previously talked about how our sleep and wake cycle are tied to our body’s temperature and how it can affect when we start to feel tired or wakeful. It turns out, perhaps not so surprisingly, that the sun and light in general also have a huge effect on our sleep cycle. A large amount of light into our eyes will wake us up and make our bodies more alert. Darkness helps our bodies wind down and prepare for sleep. Many people tote the use of blue light filters while looking at screens. These blue light filters are supposed to make the screens have a less intense effect on the eyes and make it easier to sleep at night. The problem is that the benefits of blue light blocking glasses is somewhat controversial and perhaps just a little bit of overzealous marketing. While blocking blue light can be helpful, it turns out that any form of light-blocking is beneficial for sleep. What you should be focusing on is the amount of light, not the colour of light. The reality of the relationship we share with light is one that is simple, straightforward and unfortunately hard to cheat. This relationship is based entirely on the sun. Our bodies are not designed with modern light exposure in mind. Our bodies know 2 basic things when it comes to light. The first is that when light enters the eye it’s time to wake up because the day is beginning. The second is that as light decreases, the evening is approaching and the time to sleep has come. If you understand these 2 basic principles you can greatly improve your sleep quality and also when you will wake up in the morning. It might sound simple and rather boring, but often the reality is.
So how can we utilize these two basic rules of our eyes? It turns out there are a few ways we can learn to use our relationship with light to our advantage and properly set our sleep-wake cycle. I said earlier that the amount of light matters. If you want to start getting up earlier, one of the best things you can do is get as much light into your eyes as possible, as soon as possible. Now don’t go looking at the sun, but getting outside and seeing the daylight is the best way to set your internal clock. That blast of natural light stimulates our wake cycle and “sets our clock” so to speak. You might say, “well I turn my kitchen lights on first thing in the morning, so that’s my light exposure”. Turns out, that while you may believe that you are getting a lot of light into your eyes, it’s actually only a fraction of what you would get by going out and sitting on the porch. It is very hard to substitute natural light with artificial light. Now you might be thinking, “if our kitchen lights aren’t enough to set our internal clock why would our phone screen mess it up at night?” Well, it turns out that we become very sensitive to light as evening approaches. If our bodies are still seeing a decent amount of light from something such as a phone(even with blue light filters and the dimmest setting), our sleep clocks will be delayed and we will stay up later and later each night.
As is often the case, the best way to look after our sleep habits is to return to what is more natural for us before modern conveniences. If we can get lots of light in the morning and turn our phones off at least an hour before bed, sleep will come much easier. Perhaps more importantly, waking up at 6 on a Monday morning won’t require an extra-large coffee with an extra shot of espresso.