Why Does Coffee Make Me Sleepy? Adenosine and Beyond
If you rely on your morning cup of coffee to get through the day, you may have noticed an interesting phenomenon. Sure, we all know about the stimulating effects of caffeine — many people count on a caffeine energy boost not just in the morning, but in the afternoon as well.
However, caffeine can also have the opposite effect if you’re not careful about how and when you drink it. Even if you get an energy buzz from your coffee, you might get hit with an unexpected wave of tiredness once your central nervous system calms down.
If this all sounds a little hard to believe, we don’t blame you — this goes against everything you might think you know about coffee. Read on for a full breakdown on why drinking coffee can make you sleepy.
Why Does Drinking Coffee Make You Sleepy?
As it turns out, there are actually a few different reasons why you might not be experiencing the energizing effects of coffee. In order to fully understand this phenomenon, we must first take a dive into the chemistry behind your favorite morning pick-me-up.
Increases Adenosine Receptor Sensitivity
The first reason why coffee can increase drowsiness is because it can cause a buildup of adenosine. This neurotransmitter binds to adenosine receptors to help us feel sleepy at night.
Caffeine molecules are similar enough to adenosine that they can actually bind to adenosine receptors. Because of this, coffee blocks adenosine from being able to make you feel tired.
The brain responds to this by creating even more adenosine and adenosine receptors. Once the initial effects of your coffee wears off, all of these adenosine molecules are able to bind to their receptors, causing a caffeine crash.
Keeps You Awake at Night
Caffeine stays in your system longer than you might think. Although your energy levels might return to normal two or three hours after drinking coffee, caffeine has a half-life of up to nine hours. This means that nine hours after you drink your coffee, half of the caffeine is still in your system.
If your coffee consumption tends to fall in the afternoon and evening, you may still have caffeine circulating in your body around bedtime. This can affect your sleep quality, which may make you feel more tired in the morning.
Another side effect of coffee is that it acts like a diuretic. In plain terms, it can increase urination. It’s kind of hard to get a good night’s sleep when you’re waking up frequently to use the bathroom, which is just one more way that coffee can affect sleep and cause you to feel tired.
High Caffeine Tolerance
If you’re the type of coffee drinker who needs a few cups with breakfast and a few cups in the afternoon to stay awake, then your caffeine tolerance may be too high. Our bodies constantly seek balance, and raising caffeine tolerance is just one way our bodies try to negate the effects of large amounts of caffeine.
Basically, your body will get used to the effects of caffeine, and you’ll need to increase your caffeine intake over time to keep getting the same effects. Unfortunately, this means that you’ll feel tired more quickly as the caffeine wears off.
Blood Sugar Crashes
Coffee is a nervous system stimulant, which means it activates the central nervous system to help you feel more awake and energized. One of the main ways this works is by increasing levels of cortisol, the stress hormone.
This hormone essentially activates your fight-or-flight response. This response is your body’s way of helping you get out of what it perceives to be a stressful situation.
The fight-or-flight response can have many effects on the body. It increases your awareness, slows down your digestion, and increases your blood sugar. Imagine you were getting chased by a bear — you probably wouldn’t have time to stop and eat a few berries to fuel your body as you ran away from certain death. Having high blood sugar levels solves that problem.
Unfortunately, we don’t do a whole lot of running from bears nowadays. When our caffeine consumption is too high, dysregulated blood glucose levels can cause drowsiness as your blood sugar crashes.
Too Much Sugar
If you take your coffee black, you can skip this part. But, if you like your coffee with a few pumps of flavored syrup, some whipped cream, and chocolate on top, you might want to stick around.
Many coffee drinks are full of added sweeteners and sugary ingredients. This can not only put strain on your body as it attempts to regulate your blood sugar, but it can also cause a sugar crash once your body has burned through all of that energy.
Can Other Caffeinated Drinks Make You Sleepy?
All of these possible effects of coffee have one thing in common: caffeine. Because of this, simply switching from coffee to energy drinks probably won’t fix your problems. In fact, it could make everything worse, as these caffeinated beverages often have way more caffeine than an average cup of coffee.
Tips for Staying Awake Without Coffee
After reading all of that, maybe you’re thinking about cutting out coffee. Even lowering your caffeine intake for a time can help reset your caffeine tolerance.
Here are a few tips to help you stay awake and energized as you cut back on caffeine:
- Try Decaf: Sometimes, just the taste of coffee can help you feel more energized since many people relate the taste of coffee to productivity. Look for decaf coffee beans that have a similar flavor to your regular coffee.
- Stay Hydrated: Dehydration can cause you to feel tired and sluggish, so make sure you’re drinking plenty of water.
- Go Low-Caf: Consider replacing your morning coffee with a functional alternative like our Mushroom Coffee+. Each serving only has 45 mg of caffeine, which can help keep you from those pesky caffeine effects.
- Manage Withdrawal Symptoms: When you first cut back on your coffee intake, you might notice signs of caffeine withdrawal like headaches, anxiety, sweating, and a racing heart rate. You can take time to relax, sleep, and take some over-the-counter pain relievers to help manage your symptoms.
- Exercise: Exercise can be incredibly effective at waking you up in the morning. Try going for a quick jog around the block or get your blood moving with a cycling class.
- Reset Your Bedtime Routine: Support high-quality sleep by avoiding blue light before bed, starting a bedtime routine, and making time to relax for an hour in the evening.
The Bottom Line
Most people drink coffee to power through the day, so it might come as a surprise that coffee can actually make you sleepy. While there are many reasons behind this curious case, the main reason is that caffeine blocks adenosine from being able to make you feel tired. Your brain compensates for this by creating more and more adenosine, which causes the dreaded caffeine crash.
Our bodies are pretty good at adapting. However, when you’ve adapted to caffeine so well that it takes a pot and a half of joe to get you through the day, you might need to cut back for a bit. Instead, try a low-caf option like our Mushroom Coffee+ or Mushroom Matcha+. Not only are our blends lower in caffeine, but they also feature proven nootropics like lion’s mane mushroom and L-theanine. It’s a win-win!
Sources:
Pharmacology of Caffeine - Caffeine for the Sustainment of Mental Task Performance | NCBI Bookshelf
Open for Discussion: Caffeine | American Chemical Society
