Coffee and How It Can Impact Your Sleep!
Coffee, particularly the caffeine component of coffee, has gotten much attention over the past couple of years. Usually in a bad light. In many cases, this has led people to believe coffee is unhealthy for you, when in fact coffee holds some great health benefits. The majority of these benefits are actually due to the coffee bean itself being a potent source of healthy antioxidants.
As mentioned, caffeine has had both good and bad press in recent years. The purpose of this article isn’t to shine a bad light on caffeine, because in fact, I believe caffeine can have an important place in one's diet. I’ll touch on this in a separate post - stay tuned!
The purpose of this article is to break down whether having drinks that contain caffeine after mid-afternoon is a habit you should continue with, or pack in.
It’s widely known that caffeine has a negative impact on sleep, both sleep quantity and quality. But how?
There are 3 key ways caffeine has a negative impact on our sleep:
A struggle to get to sleep
A struggle to stay asleep
Decreased quality of sleep (this is the most common one)
A decrease in the quality of your sleep is actually the most impactful as it’s easily disguised and tough to identify if it’s occurring. In most cases, the feeling of poor sleep will simply be diagnosed as being overworked, fatigue, an iron deficiency and so on.
Caffeine has the largest impact on our deep sleep. Deep sleep is the most important part of our sleep cycle. It’s what’s responsible for recovery, restorative factors and ultimately the part of our sleep that when negatively impacted, makes us feel the worst.
A quality night’s sleep should ideally consist of roughly 20-30% deep sleep.
Before moving any further, let’s first run through what caffeine actually does in our body.
Caffeine is a psychoactive stimulant, when consumed it increases activity in the brain and central nervous system, promotes alertness and encourages the circulation of chemicals such as cortisol and adrenaline.
When consumed, caffeine's principle role of action is on adenosine, a chemical in your brain.
When we’re awake throughout the day and our brain is active, adenosine builds up in our brain. The more adenosine we have, the sleepier we feel as our wakefulness areas of our brain are slowly shut down, in preparation for winding down to go to sleep.
Caffeine comes into our system and binds onto our adenosine receptors, blocking adenosine from reaching it. The adenosine chemical still stays in our brain, but without its receptor, it is unable to communicate with our brain. Therefore, making it unable to tell our brain to start preparing for sleep. This is the ‘energy boost’ we all feel after we’ve consumed caffeine. It’s not that it has energy boosting qualities, but that it blocks our ‘sleepiness’ chemicals, temporarily postponing that increasing feeling of drowsiness.
When however, the caffeine is metabolised and leaves our system, the adenosine buildup floods in and connects with its receptors (think, tsunami of adenosine) and that’s when we experience a ‘caffeine crash’.
So with that in mind, how does caffeine in the afternoon impact your sleep so many hours later?
Caffeine has what’s considered a ‘half life’ of roughly 6 hours and a quarter life of 12 hours. This means that if you have a caffeinated coffee at mid-day, 50% of that caffeine will still be going around your brain at 6pm, 25% at midnight.
This half and quarter life is fairly variable however, there’s a particular gene that will determine the speed of the clearance of caffeine from your system. Some people will have a version of that gene that’s very effective and therefore a half life to them may be only 2-3 hours. For others, it could be 8-10 hours.
Data actually suggests that having a typical caffeinated coffee within a few hours of bed can decrease your deep sleep by 20-30% on average. That’s the equivalent of aging 15 years.
When your deep sleep is drastically decreased, you’ll wake up feeling sluggish and under-recovered. For most, this is when they then reach for the coffee to help feel more awake and alert. This is where the dependency cycle begins - using coffee to wake you up in the day time and often alcohol to wind yourself down in the evening due to being overly caffeinated.
Is it true that the more coffee you drink, the less sensitive to caffeine you’ll become?
In a way, yes. Over time, as you drink more and more coffee, the body starts to become more tolerant. The adenosine receptors that caffeine binds to will actually start to get taken away from the surface of the cell due to overstimulation.
This will mean that with fewer receptors, you’ll need more caffeine to create the same effect.
This means when you go cold turkey on coffee, all of the sudden the system has equalibriated itself to expect a certain amount of stimulation, but now that stimulation has gone, you have too few receptors and you’ll get caffeine withdrawal syndrome.
Key Takeaways From This Blog Post:
Drinking caffeinated drinks after mid afternoon on a regular basis is not a good idea for your long term health, your sleep quality and will affect how you feel and perform day-to-day.
The recommended cut-off for caffeine (coffee, energy drinks, etc.) is roughly 9-10 hours prior to sleep. So, for many of us 12noon-2pm is the time to get your last cup of caffeinated coffee in.
Caffeine’s largest impact is on your deep sleep. Not only is this the most important part of your sleep for recovery, but it’s also difficult to detect.
You cannot simply avoid caffeine’s impact by drinking more and more coffee, building up tolerance.
Drinking coffee is healthy, just be conscious of timings!
We Hope You Found This Article Helpful!
I’d love to hear your thoughts on coffee, and if you’ve noticed a significant impact on your sleep. Share them with me @Olliethompsonhealth