Your digestive system has great adaptability, experts say. “The stomach has many ways to protect itself.” Still, there are a few things you should keep in mind.
I have heard that drinking coffee without food in the morning can damage the gastric mucosa. Is that true?
For many people, a freshly brewed cup of coffee in the morning is indispensable to start the day. But the idea that a sip without food could harm your digestive system — or contribute to other ailments like bloating, acne, hair loss, anxiety, thyroid problems, or painful periods, as some on social media claim — is garnering as much popularity as disbelief.
Scientists have been researching the benefits and harms of drinking coffee since the 1970s, especially with regard to the digestive system, says Kim Barrett, a professor of physiology and membrane biology at the University of California (Davis School of Medicine) and a member of the board of directors from the American Gastroenterological Association. Fortunately, the stomach can withstand all kinds of irritants, including coffee.
“The stomach has a lot of ways to protect itself,” says Barrett. For example, it secretes a thick layer of mucus that forms a strong protective layer between the gastric mucosa and everything you ingest. That layer also protects the stomach from its own natural acidic environment needed to break down food, she explains.
You would have to consume a very aggressive substance “to break down the stomach’s defenses, because it is constantly in a very adverse and harmful environment,” says Barrett. “That’s just how the stomach works.”
How Does Coffee Affect the Gut?
Irritants like alcohol, cigarette smoke, and nonsteroidal anti-inflammatories — such as ibuprofen or naproxen — are known to alter our stomach’s natural defense mechanisms and damage the stomach lining, says Dr. Byron Cryer, chief of internal medicine at Baylor University Medical Center in Dallas.
His research lab specializes in trying to understand how various drugs and other chemicals can damage the stomach and small intestine. While certain irritants can make the stomach more vulnerable to acid and ulcer formation, several large studies have shown that this is not the case with coffee. For example, a 2013 study of more than 8,000 residents of Japan found no significant association between coffee consumption and ulceration of the stomach or intestine — even among those who drank three or more cups a day.
“Coffee, even in concentrated form, is unlikely to cause objective harm to the stomach,” says Cryer. “And much less at the typical doses in common drinks.” Nevertheless, coffee has an effect on the intestines – it can speed up the colon and induce bowel movements, and coffee increases acid production in the stomach. Outside the gut, the caffeine in coffee is known to increase heart rate and blood pressure. And if you drink it too close to bedtime, it can disrupt your sleep. But these changes are temporary, Cryer said.
Will increased stomach acid cause problems?
Drinking coffee on an empty stomach probably won’t harm your stomach, but it could theoretically cause heartburn, says Barrett. We know that coffee triggers stomach acid production, but if you have food in your stomach, or if you drink your coffee with milk or cream, it helps create a buffer that neutralizes the acid. So drinking coffee without a meal, especially if it’s black coffee, can lower stomach pH more than drinking coffee with milk or with a meal, Barrett said.
While a slightly lower pH isn’t a problem for your stomach lining, it can be a problem for your esophagus, which is much more vulnerable to acid damage. In addition, some studies have shown that coffee can relax and open the sphincter that connects the esophagus to the stomach, making it easier for acid from the stomach to splash up into the esophagus and cause unpleasant heartburn.
But even there, the data is mixed. A 2014 review of 15 studies in Europe, Asia and the United States found no association between coffee consumption and heartburn, while a 2020 study with data from more than 48,000 female nurses found a higher risk of heartburn in coffee drinkers.
To understand how coffee may affect the esophagus, scientists are also studying a condition called Barrett’s esophagus, which occurs when the esophagus is damaged by chronic exposure to stomach acid, such as in people with long-term acid reflux problems. In this condition, the cells that line the esophagus change into tougher, stomach-like cells to protect against the acid. These changes can increase your risk of esophageal cancer, especially if you have a family history of this condition or if you smoke. But reassuringly, a 2016 study of veterans in the United States found no similar association with coffee consumption. The authors concluded that for Barrett’s esophagus, avoiding coffee probably wouldn’t help.
So what should I do?
Barrett: “As a gastroenterologist, I usually tell my patients in the office to pay attention to their symptoms. If they have a constant burning pain in their chest or a sour taste in their mouth after drinking coffee, they should cut back – or consider an antacid. Adding a splash of milk or cream or a small snack to your morning cup can also help. But if you don’t notice any symptoms, you’re probably someone who doesn’t experience any significant reflux after coffee and can keep drinking calmly.”
Cryer regularly drinks his coffee as a latte or cappuccino — the steamed milk reduces the bitterness, he says. And in general, he adds, drinking coffee has many health benefits, including links to longer life expectancy, a lower risk of cardiovascular disease and protection against many cancers, including liver, prostate, breast and and colon cancer.
“There’s a lot more evidence for coffee’s benefits than its harms,” says Cryer — and that’s something to keep in mind as you scroll through the social media stories that profess the cons of the brew, he adds. yet to.
© The New York Times