How Sleep Affects Weight Loss - Circadian Rhythm Explained

For many of us improving sleep is something that we view as a “maybe one day” luxury, not the potential cause of weight gain, weakness, joint and muscle pain, injury,or even a life and death matter.  The unfortunate truth is, it’s really that important.  Poor sleep could truly be the difference between feeling stuck and changing your life forever.  So what is your circadian rhythm and how does sleep affect weight loss?

How sleep affects weight loss

The truth is poor sleep hygiene affects every factor of your health, so if you’re in a fitness plateau keep reading.

There are 2 primary reasons poor sleep hygiene can affect weight loss; stress and appetite regulation.

Ultimately lack of sleep is a type of extreme stress.  Not only will you suffer the common effects of stress like cortisol spikes (which cause weight gain), low energy & poor motivation as a result of a suppression of oxytocin (our happy hormone), but you’re also missing out on recovery time.All of these factors will make exercise feel more challenging, cause more pain from exercise and to top it off you’ll build less muscle from those workouts because your body doesn’t have time to recover.  As you can imagine this leads to a rapid downward spiral.

Poor sleep hygiene also actually affects your appetite the next day.  There are 2 hormones involved in managing hunger.  Ghrelin (our hunger hormone) and Leptin (our satiety hormone).  When we’re not getting sufficient sleep Leptin is supressed and Ghrelin secretion actually increases.  This is a survival mechanism and is essentially our body’s attempt to make of for insufficient recovery time by nutrient-loading the next day.

As you can imagine between low energy, slow muscle growth/repair and a dramatically increased appetite one night of insufficient sleep can immediately begin to cause weight gain.

So What is Circadian Rhythm

Just for the sake of clarity circadian rhythm is any mental, physical or behavioral rhythm or pattern that our bodies fall into. Today we’re going to talk specifically about the most commonly known, light related rhythm. The sleep and wake cycles.  

Ever wonder how it’s possible that some nights you feel exhausted but can’t go to sleep? Chances are the rest of your body and brain didn’t get the memo to start prepping for bed. Your sleep circadian rhythm is directly affected by the amount of light taken in throughout the day in order to send the signal to the brain that it’s time to sleep. This is important because, though your brain & body might not know it’s time for bed, you always do. Unfortunately that’s not enough for quality sleep.

You see as soon as your brain receives the message from the nerves in your eyes that it’s time for sleep it starts to produce melatonin. You may recognize melatonin as the hormone that’s responsible for inducing drowsiness to help you fall asleep & stay asleep. If the brain never gets that message and doesn’t begin producing melatonin you’re left tossing and turning trying to chase after a good night’s sleep. THis is the reason bedtime routines are a vital part of sleep hygiene.

How Screen Time Affects Sleep Hygiene

Blue light has a different wavelength than natural light and is noticeably brighter. During the day (putting aside the strain on your eyes) it’s helpful because it helps to boost attention and focus. These uncommon wavelengths further suppress the production of melatonin ensuring that you stay awake and alert throughout the day. Yes, of course there are exceptions, even blue light can’t combat physical fatigue to get you through the midday slump.

Now consider that for a moment, and imagine what the compounded affect of taking in that type of light all day might be on the brain. We all know that going from wide awake to asleep isn’t as easy as flipping a switch. As you might imagine, that means your brain needs some time to wind down, to process the change in surroundings and send the signals necessary to get ready for bed.

So then what happens if your day looks like this:6:00am – Wake up, check emails facebook, instagram etc.7:00am – Have your coffee and/or breakfast and scroll through your phone to pass the time,8:00am – Drive to work9:00am – sit down at your desk, turn on your computer & get to work12:00pm – have lunch, scroll through your phone to disconnect until your break ends1:00pm-5:00pm – back at your desk6:00pm – get home, have dinner7:00pm-10:00pm – watch TV, scroll through your phone, check emails etc.

When did your brain get the signal to start shutting things down? Now sure as I said physical fatigue can of course beat the mental fatigue to some degree and maybe get you to fall asleep. But that does not equate to a restful night. Instead you’re tossing and turning all night, maybe even drifting in & out of sleep or waking up throughout the night. You end up waking up feeling exhausted, but you pour your coffee and drag yourself through that cycle again.

Now some people are probably skeptical because you feel “fine”, but what if you’ve just adapted to this perpetual fatigue so much that you just don’t notice anymore. That may sound like you’re in the clear, but imagine if there’s a chance you could suddenly get even more energy. How much more productive could you be? How much better would you feel? Could you find more time to do the things you want to do throughout the week? I think the chance at that extra energy & ultimately extra time is worth trying!

How Much Sleep Do I Need?

Though there is room for variance mot people need between 7hrs and 10hrs of sleep.  Now before you say “oh but I feel great with 5 or 6” less than 1% of the population functions optimally on less than 7hrs and it’s actually considered a sleep disorder to be a “short sleeper”.The reason you may feel refreshed is because REM cycles end after roughly 90minutes meaning waking up between 5hrs and 6hrs will likely happen after a completed REM cycle.  Even with insufficient sleep if you wake up at the end of a REM cycle you will feel less drowsy upon waking because your body is not actually trying to finish it’s cycle.

Now that we’ve debunked that myth, how do you find your sweet spot?  The easiest way to determine this is look at your sleep habit on vacation or, if you get to truly relax, on the weekends.  When you don’t wake up to an alarm and you did not consume alcohol or stimulates after 12pm make note of how many hours your naturally sleep.  To get a good gauge of this you may need to repeat this a few times simply because our body will of course replenish lost sleep for previous night which may result in longer sleep times.  As a note keep in mind that those living with mental health conditions that result in excessive sleep may need to consult a sleep clinic to get an exact time.

Of course if you aren’t interested in that much data collection when in doubt aim for no less than 7hrs per night every night.

3 Tips to Create a Bedtime Routine and Sleep Better Tonight

Here’s a few strategies you can start implementing now to sleep better tonight! First a few words of advice. As with any new habit, take small steps and do things one at a time. So don’t try to knock out everything on this list today, pick the easiest one and start there. On that same note, don’t push yourself too hard, if your goal is to go to bed at 10 and right now you’re going to bed at midnight just aim for 11:30pm or maybe even 11:45pm. And then in a few days aim to go to bed 15-30mins earlier again. Repeat this process until you reach your goal bedtime. This is particularly important if you live with other people who would also be affected by a change in your schedule.

And the last thing to point out is, this is not a quick fix. Going to bed 15mins earlier tonight or cutting out blue light earlier isn’t not going to equate to waking up with a sudden burst of energy tomorrow. Like any change that lasts, it takes time and consistency to see the change.Ok now let’s get to it.

Establish a Bedtime Routine

Again we don’t want to force anything here. So don’t pick things what you think you should do but really don’t want to do. The idea here is to eventually start looking forward to the process of getting ready for bed. So pick a couple activities that you will look forward to and that will relax you, so nothing mentally or physically challenging. That mean no studying or exercising before bed. Stretching however is a great option.I always encourage my clients to incorporate 1 physically relaxing activity (taking a bath, stretching, doing a skincare routine, etc) and 1 mentally relaxing activity (reading a fiction book, meditating, deep breathing practice, etc)

Avoid the screens

Incorporating a bedtime routine will certainly help by building in some screen free time before bed But just to run home this point, avoiding screens means all screens. So avoid watching TV, looking at your phone or turning on your computer in the last 30mins (ideally 1hr) before bed. That doesn’t mean you can’t watch your favorite show when you get home anymore or play Fortnite or Apex with your friends after work anymore. It just means maybe 1 less episode or 1 less game each night.If you have children maybe encourage more active play time with them when you get home rather than watching cartoons. Fun for the whole family, see!

Start filtering your light exposure early

Most phones have the option to turn on blue light filters now. Being someone that currently works from home and from my phone/computer I keep my blue light filter all the way up on my phone at all times. To deal with the light from my computer that I spend a lot of time staring at I use blue light glasses (linked below).

Best Sleep Aids

Below is a list of my favorite items to improve your sleep quality, my clients swear by many of the items on this list. For complete transparency this list does include affiliate links that help to support our business and the blog.

• Blue light filtering glasses
• Blackout curtains
• Weighted blanket‍
• Noise and light-canceling sleep mask
• Zero Eye Pressure Sleep Mask
• Sleep Posture Pillow

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