Drinking Coffee on an Empty Stomach? 7 Reasons Why It is Bad

By Kaivan Dave

Kaivan Dave

Founder at Awesome Coffee

Passionate about health and wellness. Living a growth mindset lifestyle. On a mission to help people feel Awesome!

March 12, 2023 | 6 min read

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You may have heard that drinking coffee on an empty stomach is bad, but is that really true? In this blog post, we'll take a look at the evidence and find out whether or not you should be drinking coffee on an empty stomach if you haven't eaten recently. Spoiler alert: the answer isn't as clear-cut as you might think! Keep reading to learn more.

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7 Side Effects of Drinking Coffee When Stomach is Empty

Drinking coffee on an empty stomach may result in the following symptoms:

Digestion issues

Drinking too much caffeine when you haven't eaten anything can lead to digestive problems like diarrhea, flatulence (gas), and abdominal pain. Drinking coffee before eating something can also cause your blood sugar levels to drop if you take it while fasting. Drinking several cups of coffee during this time can make you feel extremely tired afterward since your body is essentially running on fumes once your blood sugar crashes. Drinking caffeine on an empty stomach can cause nausea and other digestive discomforts such as gas, bloating, and heartburn.

It Might Trigger Acid Reflux

Drinking coffee has also been linked with gastrointestinal conditions such as IBS (irritable bowel syndrome) and acid reflux disease. Drinking coffee may make the feeling of heartburn worse for some people who suffer from chronic or occasional gastrointestinal (GI) discomfort or digestive problems like GERD (gastroesophageal reflux disease). Again, drinking coffee on an empty stomach doesn't necessarily mean that these symptoms will occur, but it can still be a factor for people who experience them regularly. Drinking too much caffeine and eating too little food at once may also cause nausea and vomiting by triggering your gag reflex and esophageal muscles to contract more than they normally would if you had something to eat with your drink. Drinking coffee on an empty stomach can also worsen all of these side effects since it speeds up your digestive process and can easily overwhelm a sensitive stomach. Drinking coffee with food in your stomach, on the other hand, slows down its effects significantly but still speeds up how quickly your body processes it somewhat compared to drinking it without anything which takes between 15-45 minutes at most depending on the person's metabolism.

You Could Feel Jittery

Drinking coffee on an empty stomach can leave some people feeling jittery, nervous, and anxious. Drinking coffee stimulates your muscles and nerves which affects how you feel overall. It could cause an increase in heart rate and ultimately it could affect your sleep. Caffeine has a half life between 1.5 - 9.5 hours. That means that after consuming caffeine at 8 AM one morning it could potentially take you until 5:30pm before the body eliminates 50% of it!

To find out how much caffeine you should be consuming, check out our caffeine calculator.

The Caffeine Calculator: Is your caffeine tolerance too high? Find out!

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Stress

Cortisol is a chemical that regulates blood pressure and metabolism. Some people call cortisol the stress hormone since it affects the stress level.Studies show that drinking coffee can significantly raise cortisol levels, thereby increasing stress.

Dehydration

Drinking coffee on an empty stomach may lead to dehydration or make you feel dehydrated in general if you haven't had enough water prior to drinking coffee. Drinking coffee on an empty stomach can be dehydrating because it makes your body look for water everywhere else instead of where you put it. Drinking coffee during a time when your blood sugar is low, which results from fasting or not eating, can also contribute to dehydration since it makes you urinate more frequently than normal as well as lose fluids through other means.

Headaches

Drinking coffee when you haven't eaten may contribute to headaches by spiking adrenaline levels. The spike in adrenaline levels causes narrowing of blood vessels just under the surface of your skin which can lead your head to feel like it's pounding or throbbing. It can also make you feel dizzy or lightheaded, which may contribute to headaches themselves by making it harder for you to focus.

Your blood sugar could crash

Drinking coffee on an empty stomach could leave you feeling weak since your blood sugar levels may drop. Drinking coffee on an empty stomach doesn't necessarily mean that these symptoms will occur, but it can still be a factor for those who experience them regularly.

Conclusion

When it comes to your coffee routine, there are a lot of opinions and even more questions. Do you drink before eating? How much caffeine is too much for me? Is my stomach sensitive or not so sensitive? The truth is that we don’t know how our bodies will react until we try. But what we do know is this: the best way to find out if drinking coffee on an empty stomach works for you (or doesn't) is simply by trying it! So feel free to experiment with different times and amounts of consumption - but also be sure to monitor any changes in digestion, sleep, mood, and stress as these can all affect your decision whether or not this habit suits you. And keep in mind that everyone reacts differently to caffeine, so if you drink it on an empty stomach and begin experiencing negative symptoms, take a break from it until your next meal.

Frequently Asked Questions

Can you have coffee while fasting?

Intermittent fasting can be beneficial for health from reducing body weight to decreasing blood pressure. People fasting can still get their caffeine fix in a fasted state, only if no symptoms like nausea, headache, or gastrointestinal issues occur.

When is the best time to drink coffee?

Cortisol levels spike between 8 and 9am, so it’s best to drink your morning coffee between 9:30am and 11:30am, when your cortisol levels are lowered. Additionally, drinking coffee right after a meal is the perfect time since your body already has energy from the food you ate that it will use and give you the alertness and focus you want without any discomfort or cortisol increase.

Why does coffee make me nauseous?

Some people are sensitive to coffee by either getting nauseous or feeling jittery. If you're the type who's sensitive to caffeine, consuming too much of it can lead to nausea or vomiting. Drinking coffee on an empty stomach will put your body into overdrive since it has nothing else to turn to for energy which can make it more likely to make you feel nauseous when drinking too much of it even if you're the type who is not sensitive to caffeine.

How many cups of coffee a day should I consume?

4 to 5 cups a day, or 400mg per day is recommended by the FDA as an upper limit for those who don't have any medical problems from drinking coffee. This limit however depends on your body. To figure out how many cups of coffee a day you should consume, check out our caffeine calculator. Drinking more than this could lead to dehydration or blood sugar crashes, among other symptoms, which can make it hard for you to function during the day.