Why Can Coffee Make You Nauseous? According To Science, It's All Thanks To The Effects Of Caffeine

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An early morning is never complete for me without a warm, delicious cup of coffee. That one miraculous caffeine kick can set me up for a good or bad day, depending on the level of absolute tiredness I'm feeling. What I could do without, however, is the weird AF side effects that often come with it. I've never been one to drink more than two mugs a day, but I always end up feeling strangely sick an hour or two after. So what gives? Why can coffee make you feel nauseous?

It's all down to science, baby. Caffeine can be a wondrous thing, but it can also be a detrimental part to your health if you consume too much of it. Even though caffeine be highly beneficial as a mental stimulant and can also help fight against migraines, too much can cause a myriad of side effects that make you feel like absolute hell. While some of these side effects you'd only experience if you have a lot of caffeine — I'm talking near ten cups of coffee level — nausea is relatively common, especially if you've got a sensitive stomach already.

According to Java Presse, your digestive system can be a tad touchy when it comes to the acids and caffeine associated with coffee. Even though coffee has a similar PH balance to carrots, an influx of acid in the stomach — thanks to an increased amount of coffee — can lead to various heartburn and reflux issues, and of course nausea.

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But more often than not, caffeine is the main culprit for an upset stomach. As Java Presse points out, caffeine actually "encourages your stomach to produce more acid than usual," so this combined with the stimulant's laxative effect that "forces your digestive system to work faster," it's no surprise that you may feel a little sick thanks to what's going on in your insides. And yes, it's thanks to that laxative effect that you are often left with a sudden urge to go to the toilet *shudders*.

If you feel like these two facts aren't why you feel nauseous after drinking coffee, it also depends on how you're drinking it. Not down to like a specific brand or a special mug, but when and what with. There have often been days where I wake up and completely disregard breakfast and go straight to the coffee machine, and that can often be detrimental to my day and make me feel like absolute crap.

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And it all comes back to those acids. According to Curiosity, having food in your stomach before drinking coffee "will prevent the extra acid from eating at your insides," which can also help stop you from feeling icky. If you continuously drink coffee sans breakfast, "the hydrochloric acid your body produces will damage your stomach lining." Yikes.

You can also backfire the hormone cortisol that you get by just waking up in the morning thanks to the caffeine, which can actually result in you feeling even more lethargic than you first felt getting up in the first place. It is suggested that coffee "in the mid-morning or afternoon" is your best bet, as this is "when your cortisol levels begin to dip."

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Lastly, you've got to stay hydrated. While a study from the NHS reported that a "small amount of coffee will not dehydrate you," I've always found that drinking a glass of water as the first thing I drink after I wake up makes me feel ten times better than going immediately for the coffee.

But you could be entirely different. It's all about learning how your body reacts to things, and how to prevent unwanted side effects. Especially when it comes to sweet, sweet coffee.