Living Naturally According to Our Evolution Part 1: Sleep and Light

As a student of both spirituality and of science, and a curious psychology graduate, I’ve done a lot of less common research. 

A topic a lot more people are touching on these days, or reaching for without knowing it, in the age of information, is how do I live more naturally?

Most people when they think of “Paleo” think of the diet. And even then they may have misconceptions. There’s a thing called the “Paleo lifestyle” which encompasses a lot of these ideas. Basically living according to our biology, our evolution. But here in this blog series, I’ll go further than that based on my understanding of neuroscience, psychology, and evolution. And of course, my own experience. 

When the blue light of the Sun disappears, that's when your body signals that it's time to sleep

Sleep

Good sleep is considered one of the leading health predictors in current research. It also impacts our mood and energy levels. The sleep cycle is regulated by a hormone called Melatonin.

Melatonin triggers the wake cycle with exposure to the blue light in sunlight, and the sleep cycle in its absence. As is well known, you have a body clock, that regulates not only sleeping but hunger via hormones. Cues in your lifestyle and environment determine this clock. Blue light is also present in artificial lighting and computer, TV and mobile screens. 

In fact, our sleep is so different from before the event of artificial lighting, that we used to sleep in a biphasic manner, sleeping for roughly ten hours, with a period of waking briefly in the middle. This is all throughout our history books. Keeping in mind that darkness spanned up to 14 hours each night, and prior to artificial lighting, most of our evolutionary period was lit by this little wonder:

The dim, warm, hypnotic light of candles and fire do little to upset our sleep or melatonin regulation

So one of the best things you can do for your sleep is to reduce artificial lighting. Go for dimmer bulbs with a warmer light, or use specifically blue blocking bulbs. Avoid fluorescent bulbs. Use a program like f.lux or Windows 10's 'night light' to reduce the amount of blue in your screens. 

Use dark mode as well (blue is contained in white obviously). Something not much brighter than some candles is ideal for evening lighting, or at least like a dimmer lamp.

There are apps for warming the colours of your screen on Android too. Screens are very bright, so try to reduce screen time in the evening, or at least also have it a bit dimmer. 'Adaptive brightness' is a nice thing to switch on as well, basically, this uses your phone's camera to detect the brightness of your surroundings, and adjusts the screen brightness. 

You'll feel sleepier, sooner. 

Something like this can be used to emulate our ancestral habit of sleeping on things like  fur rugs.

The last element of sleeping is how you sleep. There's not a lot of science on the topic, but it's generally thought that mattresses that are too soft can lead to back issues in the morning. Anecdotally a lot of people wake up feeling sprier and with fewer back issues on harder surfaces. 

Paleo lifestylers have taken to sleeping more like a floor arrangement; using futons or foam mattresses, something with a bit more firmness than a spring mattress. Keep in mind, you do need something to provide airflow to prevent mould if you sleep on the floor itself. There is a special material they use on boats for this, or you can use something like a futon base or a grass mat like they use in Japan. Any mattress should be turned and aired occasionally too.

Note people who have back issues, or are elderly, might not be able to sleep this way.

You don't have to sleep on the damned forest floor, but getting out in nature is good for you

Light and Nature

Light also plays a role in our mood. Not only does sunlight convert to vitamin D, useful for the immune system in our body (and cancer-preventing), and triggers your wake cycle, but sunlight also increases a compound called “Brain-derived neurotrophic factor” which is known to have a direct impact on our mood. It makes you happier. 

Hence why people get depressed in the winter. And just like bad sleep is correlated with numerous physical problems, BDNF when it's low is associated with mental illness, and when it's high, not only good mood but good cognition and long-term memory. 

So one should absolutely maximize exposure to sunlight during the day. Obviously direct midday to afternoon summer sunlight on the skin, you should use some sunblock, but in general, your skin and your eyes need to receive sunlight, to be healthy.

There's a reason you like gifs like this. Science, baby

The other thing about getting out is this interesting thing that happens in nature. We all know being in nature occasionally is soothing, but there’s a science on why. It’s a form of gentle attention. Things like the sway of trees, the tinkling of water, the sound of the wind, draw a gentle but inactive form of attention that lowers stress.

Not only does it lower stress hormones, and relax you, but it actually recharges you. As you'll see in the article in the references, this gentle attentional break offered by nature, actually increases focus, higher order functioning and basically makes you better at thinking and focusing. We need it like we need rest. 

So whilst you are getting your dose of mood-lifting, sleep enhancing, health-boosting sunlight, try getting a taste of the old green brown and blue and spend some time outside of built-up city buildings. 

Spend time by a stream, some birds or the sway of the trees.  

Part 2: Clothing and People

References

Biphasic sleep: Link 

Gentle attention and nature. Link 1 Link 2  

Benefits of floor like sleeping arrangements: Link 

Wikipedia on Brain-derived neurotrophic factor: Link 

BDNF and mood: Link 

Blue light and sleep: Link