How Can I Sleep Better?
Caffeine, Sleep Pressure, and Adenosine
Welcome to entry number 3 in this series where we decipher how to sleep better and what tools to use to achieve that goal! So far, we have discussed some definitions of sleep latency, efficiency, and opportunity as well as melatonin. Today, we’re going to be focusing on caffeine and adenosine. Adenosine seems like one of those sciency words, but I promise it will make sense and not be intimidating as we go through this. Are you ready?
It's no surprise to anyone that caffeine keeps you awake. Anyone who is sleep deprived can you tell after a few cups of coffee, they’re awake and ready to go but why is that? Moreover, what about the people who consume caffeine before bed and fall asleep just fine AND stay asleep? Does caffeine not affect them? All of these are great questions that brings nuance to the discussion of caffeine’s role and impact on your sleep. Remember that sciency word I mentioned earlier adenosine? Caffeine largely interacts with it to the affect that you’re used to. Adenosine is a chemical in your brain that is naturally produced in all of us from the moment we wake up. Whenever you feel tired, even slightly, what you’re feeling is a build up of adenosine in your brain. That’s what we call healthy sleep pressure, and it is often the measure people use to determine when to go to bed. Caffeine “wakes you up” by essentially blocking the adenosine receptors in your brain. It doesn’t take that sleep pressure away, but it does prevent you from feeling it.
Sleep pressure is an interesting thing because it is typically seen as a hinderance in our society. You feel sleepy through the day? Drink some caffeine! Take a walk! Wake yourself up! All of these make some sense, but we have such a damaged relationship with sleep because it’s seen as something that impedes progress. We need that sleep pressure, and we need it consistently to try and be as in tune with our natural circadian rhythms as possible. We’ll go over naps in another blog posts, but sleep pressure and naps are often at odds and as a result, it can cause many issues. Being sleepy isn’t the enemy. Listen to your body when your adenosine is high. It means something important and it’s worth listening to!
Homework time! We’ll make this multiple choice. What is the quarter-life of caffeine in your body? A. 4 hours B. 8 hours C. 10 hours D. 2 hours If you said C, you’d be right! It’s more like 10-12 hours on average but 10 is close enough. So, what does this mean exactly? What this means is that 10-12 hours after you take a swig of coffee or any product that has caffeine, like chocolate, about a quarter of that caffeine is still having a nice swim in your brain. Because it blocks the adenosine receptors, it fools you into thinking you’re not as tired as you really are. This can cause you to go to bed later and then when you get up early, you depend on caffeine throughout the day to stay awake. This creates a vicious cycle where Starbucks makes bank offyou while your sleep suffers greatly. “Are you telling me that I can’t have coffee 10 to 12 hours before bed? That’s insane! I have to wake up early and I need the caffeine to do my job!” The answer to your question is yes, the recommendation is that you stop drinking caffeine 10-12 hours before bed so you can sleep properly. “Ok, but I drink a soda or something an hour before bed often and I sleep just fine. That must mean caffeine doesn’t affect me!” Even if you can fall asleep and stay asleep after consuming caffeine before bed, even a couple hours before bed, your sleep still suffers. Studies show that caffeine blocks your deep sleep, stages 3 and 4 of NREM, so your quality of sleep suffers as a result of that caffeine consumption. Do yourself a favor and try to go 1 week without consuming caffeine 10 to 12 hours before going to bed. You may feel more tired in the morning, but you will start to notice that you sleep better because that healthy sleep pressure builds up and motivates you to sleep.
The purpose of this blog post, or any of my posts, is not to tell you how to live. If you want to keep living life how you are, that is well within your prerogative. I am merely giving you vital information to help solve some sleep issues or perhaps enhance the sleep you are getting now by changing some sleep habits, changing your perspective on sleep, and learning some sleep hygiene. Life is to be lived but it should be lived as informed as you can be!
Thank you for taking the time to learn a little more about sleep and caffeine. I will say bye for now and I wish you restful sleep!
Fun fact for your next party: Caffeine blocks your deep sleep between 10% and 30% on average. In order for that to happen naturally, you would have to be aged by about 10 years.