Is Drinking Coffee on an Empty Stomach Bad for You?

Doctors and nutritionists share the truth.

That first cup of coffee in the morning can make getting out of bed worth it. After all, a few sips of the magical caffeinated potion can transform you from feeling like an extra from Night of the Living Dead into a real, live human.

But is drinking coffee on an empty stomach a good idea when it comes to your gut health? We asked the experts what exactly happens when you enjoy a pre-breakfast pick-me-up.

Is Drinking Coffee on an Empty Stomach Bad for You?

The good news is, according to Dr. Jill Carnahan, MD, a functional medicine expert and author of Unexpected, the short answer is no. She says that there is little scientific evidence that drinking coffee on an empty stomach is harmful to most people.

In fact, Dr. Steven Gundry, MD, heart surgeon and founder of GundryMD, says that for most people, drinking coffee on an empty stomach is fine. And in fact, he highly recommends coffee in general, in part because of its high polyphenol content. “These essential plant proteins in coffee promote everything from longevity, protection from Alzheimer’s disease, a normal weight, a healthy microbiome, and remarkable relief of depression and anxiety,” he says.

However, due to the high acidity of coffee, it may irritate the stomach of patients who suffer from gastritis or GERD. “If you are suffering from frequent heartburn or have been diagnosed with gastritis or a gastric ulcer, it is best to avoid drinking coffee on an empty stomach,” she says.

How Does Coffee Affect the Gut?

Dr. Carnahan explains that like cocoa, coffee comes from beans and contains high levels of polyphenols and antioxidants. “In fact, for many people, coffee is one of the primary ways that we get these polyphenols in our diet,” she explains.

Both coffee and dark chocolate contain nutrients for the microbiome which can be processed into a highly beneficial nutrient referred to as SCFAs (short-chain fatty acids). “SCFAs have been shown to help repair the cells that line the gut and create a nutrient-rich environment in the gut related to improvement in metabolic health, obesity, risk of diabetes and heart disease,” she continues. “Increasing the SCFAs by drinking coffee is quite beneficial to the microbiome of your gut.”

But coffee is acidic, which can be irritating to anyone with a sensitive gut or someone already experiencing digestive issues, says Abigail Hueber, RD, LDN at Above Health Nutrition. “Most notably, coffee can irritate heartburn as caffeine is a relaxant to the sphincter that controls acid staying in the stomach versus moving inappropriately back up into the esophagus.”

Serena Poon, CN, CHC, CHN, celebrity chef and nutritionist, points out that some research has found that people who experience a negative reaction to coffee will have it regardless of whether or not they drink the beverage with food.

Hueber adds that coffee also stimulates cortisol release from the adrenals, which creates a stress response in the body and can exacerbate gut symptoms such as loose stools or even constipation—which explains why many people tend to do their business shortly after drinking a cup or two.

However, Poon explains, “This hormone naturally circulates at higher levels in the morning, so there is a line of thinking that drinking coffee in the morning further increases cortisol, but it really depends on the person.” She adds that prolonged elevated cortisol begins to lead to inflammation and can wreak major havoc on the body, but there is no direct path to chronic inflammation from regular coffee consumption. “In fact, research points to coffee’s anti-inflammatory benefits. What’s more, some studies have found that some people (namely regular coffee drinkers) did not experience a cortisol spike in response to coffee,” Poon says.

Tips on How To Minimize Any Harm

“If you have negative reactions to coffee, such as heartburn, digestive discomfort or nausea, or an increase of feelings of stress and anxiety, I would recommend experimenting with a change in habit,” says Poon.

Here are a few expert-recommended tips, because hey—who wants to give up their coffee?

Think twice before adding dairy

According to Dr. Gundry, many people believe that black coffee irritates the stomach, so they put milk products into coffee to “soothe” the stomach. However, he points out that many of the benefits of coffee are undone by adding any milk product like skim, 2%, whole, half and half, cream and even butter.

Add a non-dairy milk

That being said, for some people, a small amount of non-dairy milk can sometimes help ease any issues that arise because of coffee consumption. "If you drink black coffee, you could consider adding a small amount of non-dairy milk. I would go with an unsweetened, non-dairy, preferably homemade milk,” says Poon.

Try adjusting your dosage

You may also consider cutting down on your consumption. “One cup of coffee a day and four cups of coffee a day are going to impact your system much differently,” Poon notes.

Consider switching to tea

If coffee is wreaking havoc on your gut, consider a switch to green tea or matcha, “which still contains caffeine, but may not be as hard on your system,” says Poon. “Plus it is full of potent antioxidants that support health.”

Consider what you are adding to your coffee

Drinking a cup of coffee black isn’t the same as a sugary latte. “Keep in mind that common additions to coffee, such as dairy and sugar might also cause digestive discomfort, so it might be a good idea to bring those habits up for review as well,” suggests Poon.

Use alkaline water

Reconsider using tap water to make your coffee, says Dr. Carnahan. “One simple hack I recommend for patients with sensitive stomachs is to use alkaline water to make your coffee to decrease the acidity of the final brew,” she says.

Long story short: Coffee on an empty stomach can be irritating for people who already deal with stomach issues, but there's no evidence that drinking coffee on an empty stomach is harmful to others. And even if black coffee does tend to irritate your gut, a few simple tweaks (bring on that splash of almond milk!) may work wonders for you.