Watch sunrise to wake up early!
“What!! Isn’t it the other way around?”
Well yeah, we can wake up early and watch sunrise for sure if we are interested. But if you are having trouble waking up, one of the best ways to change your sleeping pattern is to (forcefully) wake up for the first few days and watch sunrise.
Isn’t it funny — “Wake up early to continue to wake up early”. Lemme explain the science behind it:
1. Activating the internal clocks
In layman’s terms, our body is made up of cells and each cell has a clock of its own. There’ll be a master clock sitting in brain known as suprachiasmatic nucleus (SCN) and if we activate it, it’ll send signals to other cells which inherently brings us to awake state.
Good! So the goal is to activate suprachaismatic nucleus (SCN) and tell it to send signals to rest of the body that we are awake. But how to do that?
2. Eye to brain
Our eye has lots of connections to brain and we are particularly interested in a particular kind known as ganglion cells (connections from other parts of eye to brain). One type of ganglion cells is Photosensitive retinal ganglion cells and it connects to suprachaismatic nucleus (SCN)
I guess now you can start connecting the dots…
Wake up early in the morning and watch sunrise → Light hits retinal ganglion cells → Information passes to SCN → Activates SCN which sends signals to other parts of body → Awake state achieved
You might question: “This helps in being awake in the morning, but how does it help in waking up early (or change sleep pattern)?”
3. Circadian rhythm and phase shifts
Remember the concept of phase shifts from the previous blog!! More details this time..
Circadian rhythm is nothing but the sleep-wake cycle. It’s usually a bit longer than 24hrs and varies a lot from person to person. All the functions of our body are tightly linked to this rhythm as this is the one which determines the state our body is present and controls actions accordingly (using more energy to digestion while sleeping etc;)
Sometimes, we want to be wakeful at particular times (travel, exams) and want to be sleepy at other times (very rare). The way to achieve this is to shift the circadian rhythm. And how to shift this rhythm?
Suppose your usual wakeup time is 8AM. Now, if you (somehow) become wakeful at 6AM for few days, your body starts to readjust it’s clocks (phase advancing — you feel wakeful before your usual wakeup time).
The same works for phase delay as well. Suppose you sleep (or your body signals the sleep state) at 10PM . Now, if you (somehow) become wakeful till 12AM for few days, your body starts to readjust it’s clock (phase delaying — you feel wakeful after your usual sleep time).
And how to be wakeful? Connect the previous dots with this piece and voila, here’s the whole science:
Wake up early in the morning and watch sunrise → Light hits retinal ganglion cells → Information passes to SCN → Activates SCN which sends signals to other parts of body → Awake state achieved before our usual wakeup time → Phase advanced (if repeated for few days) → tends to fall asleep earlier than usual bed time → enforces to wake up early the following morning.
4. What can I do if I can’t see sunrise?
It’s a genuine case for people living in Nordic regions. Artificial light helps one to bring to wakeful state but there’re limitations:
a. Turn off the blue blockers if you use any:
You might have had a strong opinion that blue light damages your eye, so it’s always needed to have those blue blockers. It’s not entirely true. The blue wavelength helps to activate the SCN. So, get blue light by turning off your screen blockers at early hours to reach wakeful state.
b. Get 100k Lux by the end of first hour after you wakeup:
Our retinas are not sensitive at early in the morning, so we need more light (as much as 100k Lux) to activate SCN.
A rough estimate is that sunlight has 10–20k Lux (even on a cloudy day) and a bright room with all lights turned on has around 1000 Lux. Now do the math and you will understand how much time it’ll take to become wakeful by artificial light.
c. Place the artificial light above the eye plane:
The ganglion cells are at the lower half of the eyes and as eyes act like lens, light coming from upper half of the eye plane hits these cells. So, a ceiling light (light overhead) is better than a bed lamp to achieve wakefulness.
If you depend on sunrise, then this factor is automatically taken care as the sun will be above us (I’ve never seen sun with eyes down :P )
Note: Candle light won’t help to reach the wakeful state as it lacks the blue wavelength required to activate SCN and won’t disrupt the circadian rhythm.
5. What about sunset!
Watching sunset helps us to fall asleep :) Remember our parents asking us not to use phones at night. It is for a good reason:
Using phones → Emits blue light which suppresses melatonin secretion → Wakeful state at night (which is not what we usually desire)
Now, watching sunset readjusts the sensitivity of retinal glands and tells brain something like: “Okay, it’s about to go to bed 3–4hrs from now as the world gets dark, so start secreting melatonin”. So, even if you use phones at evening/night, the melatonin would have been secreted by then and thus you will sleep at your usual bedtime.
It’s like damage control. The best way to reach sleepy state is to avoid using phones, artificial light above eye plane before 3–4hrs of your bed time. But if it’s inevitable to use phones (obvious in today’s era), then watch sunset to compensate for the damage you are about to get at night.
And don’t forget to turn on the blue blockers that you turned off at morning :P
6. What about night shift workers?
Hmm..here’s where things get interesting. For them, “sunset is like sunrise and sunrise is still like sunrise”
For nightshift workers, the wakeful cycle is something like 7PM — 5AM. So, watching sunset at 7PM or so helps them to be in wakeful state. But watching sunrise shifts their circadian rhythm and it’ll be difficult for them to go to bed at 8AM or so, which makes them to wakeup late.
We can’t tell brain something like: “Well, it’s bed time as the world gets bright” as we are wired to be diurnal beings (awake at morning, sleep at night.)
Temperature minimum (the time when your body is at lowest temperature) of day workers come around 4AM. So, they tend to wake up at 6AM and be wakeful till 6–7PM (the temperature rises continuously till then) and the sleep signals start (melatonin secretion, temperature dip etc;), so they sleep at 10–11PM.
Now, for night workers, the temperature rhythm looks opposite. Their temperature minimum comes around at 4PM. So, they tend to wake up at 6PM and be wakeful till 6–7AM (the temperature rises continuously till then) and the sleep signals start (melatonin secretion, temperature dip etc;), so they sleep at 10–11AM.
Now, anything that disrupts this temperature cycle inherently disrupts the circadian rhythm and sunrise has that potential.
7. Can I watch sun at any point of time and achieve the wakefulness?
Sadly, it’s a no. You have to watch sunrise only after a couple of hours after your temperature minimum (around 3AM) which is usually in the morning before 9AM. So, watching sun at 11AM won’t help in becoming wakeful. Usually 11AM-4PM is known as circadian dead-zone and watching sun/artificial lights won’t change your circadian patterns (i.e no affect on wake-sleep cycle)
8. How does SCN helps in achieving awake state?
This is an in-depth and complex topic but an approximation is something like this:
Assume we wakeup at 8AM. When we trigger SCN using sunrise, it sends signals to release cortisol (the wakefulness signal) and sets timer approximately 12–14hrs later i.e (8PM-10PM) to release melatonin which helps us to fall asleep.
Disclaimers
When it comes about health, it’s obvious to have disclaimers isn’t it! So, here it goes:
- I am not an expert in this field, so don’t take the advice for granted. This blog is inspired from Huberman Podcast, an excellent podcast, highly recommend for everyone who wants to learn about science and science based tools for better life.
- When I mean to get more light, it’s not about staring at light source. Definitely don’t do anything that irritates eye.
P.S: I am trying to make notes for this podcast and some occasional (condensed) blog posts. The detailed notes can be referred here. This notes is not a replacement to Huberman podcast and it’s best used as a reference material. Once again, do checkout the podcast as it’s highly packed with lot of good stuff. It’s available in Youtube, Spotify, Apple Podcast etc;