One of the favorite past-times of Americans (and increasingly people around the world) is to wake up with a cup of coffee. However, many people have heard before that drinking too much coffee can lead to ulcers. Is there any truth to this?
The Coffee and Ulcer Relationship
Back in the mid-1900s, it was actually thought that coffee was a cause of ulcers, along with a poor diet, stress, and drinking. Modern science has revealed that this is not the case.
Now, we know that the two primary stomach ulcer causes are H pylori infection (H pylori is a bacterium that colonizes the upper digestive system) and regular usage of NSAIDs (medicines like ibuprofen, naproxen, and aspirin). With that said, coffee does have a few effects on the digestive system.
Of Coffee and Stomach Acid
Coffee, particularly when consumed on an otherwise empty stomach, result in indigestion, so it is not surprising that people believed that coffee caused ulcers.
What coffee does have in it is caffeine, and the caffeine stimulates the release of stomach acid (as do most stimulants, like nicotine). This frequently results in heartburn (i.e. acid reflux), the symptoms of which are frequently mistaken for stomach ulcer symptoms. Additionally, drinking coffee when you already have a known ulcer can indeed irritate the ulcer via the increased secretion of stomach acid. Note that even decaffeinated coffee seems to increase stomach acid production.
This relatively minor increase in stomach acid is not enough to cause an ulcer in its own right; a more destructive force like H. pylori (which disrupts the protective lining of the digestive tract) or NSAIDs (which reduce the secretions of the protective coating of the stomach) to actually cause an ulcer.