📚Why Does Caffeine Make Me Tired? The Truth About Coffee and Tiredness

My morning coffee is something I cherish. Often, I don’t quite feel like myself until after I’ve sipped on that first brew. However, there are mornings when I’m so exhausted that even a strong espresso barely makes a difference. Actually, sometimes it’s the complete reverse. I drink a coffee hoping it’ll give me a boost, but within twenty minutes, I find myself struggling to stay awake at my desk! This made me question ‘why does caffeine sometimes make me tired?’

Can caffeine make you tired? I looked into it, and the answers surprised me! Read on to find out why coffee can actually make you more tired, why this happens, and what you can do about it.

Coffee Dehydrates You

Coffee is a diuretic. This means it makes you want to pee. So you go to the toilet, which dehydrates you. And right now what you’re drinking is coffee, so you drink more coffee. Which makes you want to pee. You see where this is going? It’s a vicious cycle.

It also doesn’t help that one of the major symptoms of dehydration is tiredness. Obviously, if you feel tired, you’re going to want to drink a refreshing cup of coffee to wake yourself up. But what your body really needs is water.

What Happens When We’re Dehydrated?

See, when we get dehydrated, our blood gets thicker, because there’s less fluid in our bodies. This means that it moves slower, so less blood gets to our organs. This means less oxygen also gets to our organs. All of these actions combined slows us down and makes us feel tired. Then, because you’re tired, the reflex is to down more coffee to make up for it.

So make sure you keep yourself hydrated by reaching for the water in between cups of coffee. Keep a bottle on your desk, and make sure you drink water whenever you come back from the loo. Even if you only drink one cup of coffee per day, or during the morning at least, it will aid the dehydration, and you would be wise to drink some water after that cup as well. Since I noticed that caffeine makes me sleepy sometimes, I started drinking more water, and it actually helps.

Your Body Can Get Resistant to Caffeine

When you’re tired, your body produces a hormone called adenosine, which binds to special receptors in the brain and lets your mind know you’re tired. But caffeine blocks this hormone by binding to these same receptors, stopping our minds from realising we’re tired. But it doesn’t stop our bodies from producing the hormone, and doesn’t stop our bodies from being tired.

So when the caffeine wears off, all of the sleep hormone that’s built up in our bodies comes crashing into our brains, which makes us far more tired than before. Which generally leads to us cracking another cup of coffee to try and make us more awake again.

What Can Happen When You Drink Too Much Coffee?

On top of this, if your brain regularly finds itself using the vast majority of these sleep hormone receptors, it creates more to deal with the increased demand. But your brain doesn’t know whether the receptors are being taken up by adenosine or caffeine. So if you regularly drink coffee every single day, you’re teaching your mind to be less and less receptive both to caffeine and sleep hormones.

This is why your body gets more resistant to the effects of caffeine over time, and why caffeine makes it harder to get to sleep. You’re literally training your mind to resist the effects of being tired.  

Sweet Sweet Sugar

I’m guilty of this one. I’ve always had a sweet tooth, and I love a spoon or two of sugar in my hot drinks. But the sugar in sweet coffees can easily cause a sugar crash. Especially if we’ve also not eaten too much in the same day. So if you’re guilty of regularly having just a coffee for breakfast, you might want to pay close attention to this one.

In fact, studies have shown that the particular combination of sugar and caffeine found in things like coffee and energy drinks has an incredibly particular effect on the body. It can increase blood sugar levels by a significant margin. But because sugar is processed by the body much faster than caffeine, the sugar rush wears off way before the caffeine high. This causes a major variance in insulin levels and actually affects the way your body processes sugar in the future.

Try Without it

This is especially important if your regular drink is a sugar laden, chocolate flavored, cream topped frappucino. In this case, it could even be that your body isn’t responding to the caffeine, but the sugar.  

If you regularly drink a lot of sugary coffee, try changing to a simple black with no sugar for a couple of weeks, and see how it affects you. Or even cut it out altogether for a little while.

You Could be Genetically Vulnerable to Coffee

There’s actually a specific enzyme in our bodies that affects how we process caffeine. It’s called CYP1A2, and it determines how quickly and easily your body can break down and deal with the effects of caffeine. Most people are fast metabolizers, so their bodies quickly break down the caffeine in their blood, and it’s generally absorbed within 30 minutes.

But for a few people, their genetic makeup means they can’t produce enough of the enzyme to break down caffeine properly, so it sits in their body without being absorbed, and has little to no effect. This means that no matter how much caffeine you have, it’s not going to do anything for you, besides being a placebo.

You can get tested for this, but for most people, it’s not something they’re really going to have to worry about.

What You Should Do

So remember, to avoid fatigue when you’re drinking caffeine:

• Control your caffeine intake so you don’t develop a tolerance. Try not to have more than 2-4 cups of coffee a day
• Avoid adding too much sugar with your coffee to avoid a sugar crash
• Make sure you’re drinking water alongside your coffee to avoid dehydration

Final Thoughts

So, long gone are the days when I could ask ‘why does caffeine make me tired?’ Now I understand what I’m putting into my body, and know how to fight the effects of caffeine and how to deal with my fatigue, it’s a lot easier to stay awake and I feel all the better for it.

Do you drink coffee every day? Have you ever felt more tired after drinking a cup of coffee? If you’ve got any cool stories or interesting experiences, we want you to comment below and share them with the rest of us!