About 60% of coffee drinkers experience some sort of discomfort, including an uneasy stomach, right after drinking a good cup of coffee. This normally isn’t an issue that needs any sort of medical attention, but it’s not exactly a pleasant side effect of the drink we all know and love. So, what can you do to prevent an upset stomach after coffee?
Because coffee has an acidic pH value of roughly 4.5 to 5.1 and a high caffeine content, it often causes an upset stomach. To avoid this side effect, try not to drink coffee on an empty stomach and limit the use of added flavors and creamers.
Let’s take a closer look at how coffee affects your stomach and what you can do to prevent the discomfort that tends to accompany your morning cup of joe.
Why Coffee Could Be Upsetting your Stomach

Coffee is a great source of energy and the morning beverage of choice for many people across the globe. It possesses several beneficial elements, but it’s also got its pitfalls. One of the most prevalent side effects of coffee is that the gut doesn’t always respond well to it.
That could be down to many reasons; however, the science behind it is that caffeine is a stimulant and, at times, it stimulates the inner mechanism of your gut too. What’s more, coffee’s packed with a wide array of elements that interact with the digestive system.
Let’s go through some of the various ways coffee impacts your gut.
Acid Levels
Most coffee varieties have an acidic pH value, ranging from around 4.5 to 5.10. The acid mostly comes from the brewing process, because as the heat extracts the flavor and aroma, it also extracts acids.
Naturally, when coffee reaches your gut, it raises acid levels there. This is an issue because higher-than-normal levels of acid can cause acid reflux, heartburn, and even nausea. In many cases, it also stimulates bowel movements.
If you’re curious about the exact caffeine content of your morning cup of coffee, you can test it with pH test strips (on Amazon). Simply take the strip and dip it in your coffee. A color change to greenish yellow indicates an acid level of 3 to 6.
Caffeine Content
Caffeine can be a double-edged sword: On the one hand, it stimulates your nervous system to make you feel alert and energized, but on the other hand it triggers your gastrocolic reflex.
The gastrocolic reflex is a mechanism that gets moving down there in response to stomach stretching during and after a meal. However, scientists have concluded that caffeine may also trigger this reflex.
Simply put, ingesting coffee sends signals to the brain to activate the gastrocolic reflex. In response, the colon experiences stronger contractions, which ultimately causes the urge to defecate.
Another theory states that it’s not the caffeine at all, but rather a coincidence since coffee is generally ingested at times when the gut is most sensitive.
Added Sugars and Flavors
Add-ins like maple syrup, honey, and cream offer a great experience for your taste buds, but not such a great one for the gut. Let’s take sugar for instance. To be digested, it needs to be broken down and absorbed. But what if you consume an excess amount of it and only a portion is digested?
Well, the portion that’s not digested will sit and ferment in your bowels. And as it moves very slowly through your large intestines, it feeds off of yeasts and bacteria to form a mass of gas. This can be a very painful experience.
There’s also the fact that most of these additives contain dairy. This can be especially damaging to your system if you’re lactose intolerant.
Roast Type
When it comes to the level of roast, it depends on what your system is more sensitive to — caffeine or acid. As explained above, both caffeine and acid can do a number on your stomach. And both of them are dependent on the roast level.
Light to Medium Roast
Less than 6 minutes of roasting coffee beans will get you a light to medium roast. In spite of the light color, light roasts (on Amazon) pack nearly twice as much caffeine as dark roasts (on Amazon). With that being said, if caffeine triggers your bowels, then you should steer clear of light roasts.
Medium to Dark Roasts
Roasting your beans past the second crack sound will yield a dark roast. Dark roasts are characterized by their high acidity levels but lower levels of caffeine. This is the roast type that raises acid in your gut.
What You Ate Before
In some cases, it could even be something entirely different upsetting your stomach. For instance, what you previously ate. Foods don’t just magically disappear into our gut after we consume them. They go through a process called digestion.
Different foods are digested at different rates depending on the type of food and your tolerance of that food in particular. Some food items can take up to 4 hours to fully be digested. When you down a coffee while your body’s still digesting previous foods, the compounds in the caffeine may react with those foods and wreak a havoc in your gut.
It could also simply be that your gut didn’t respond well to those foods and you are conicidently feeling the side-effects after drinking your cup of Java.
How Fast You’re Drinking Your Coffee

Something as simple as the speed at which you down that morning cup could be behind your coffee nightmare. The short of it is that when you drink fast, you swallow more air, which causes gas build-up and bloating.
Bloatedness will make you uneasy in many ways and at times, it triggers uncomfortable contractions.
How to Avoid an Upset Stomach
Seasoned coffee drinkers are familiar with the way their body respond to different elements of coffee, and, as a result, they’re usually able to avoid most of the side-effects. This may prove challenging when starting off with coffee.
In simple terms, you’ll need to know your body’s natural response to caffeine and how to counter it. This will require a bit of trial error at first, but it’ll eventually become second nature. Try implementing the following tricks:
- Avoid drinking coffee on an empty stomach
- Limit sugars, flavors, and dairy-based milks
- Go for decaf if you’re sensitive to caffeine
- Opt for a less acidic option, such as cold brew (on Amazon)
Conclusion
Coffee is a versatile drink that affects your body in several ways, and, as such, it also affects your internal organs, particularly your digestive system. You may not be able to pinpoint the exact source of your upset stomach but you can implement a trial and error approach to figure our what the issue is.