ScienceDaily — Stomach irritation preventing almost two out of every 10 people from enjoying coffee. Now, scientists report the discovery of several substances that may be among the culprits responsible for brewing up heartburn and stomach pain in every cup.

Their report, presented at the 239th National Meeting of the American Chemical Society in San Francisco, included the counter-intuitive finding that espresso, French roast, and other dark-roasted coffee may be easier on the tummy because these roasts contain a substance that tells the stomach to reduce production of acid.

The research could lead to a new generation of stomach-friendly brews with the rich taste and aroma of regular coffee, the scientists said.

"This discovery is going to help a lot of people who suffer from coffee sensitivity," say Veronika Somoza, Ph.D. from the University of Vienna in Austria, and Thomas Hofmann, Ph.D. from the Technische Universität München in Germany, who conducted the study. "As coffee-lovers, we're very excited about this research."

Estimates suggest that up to 40 million people in the United States alone either avoid coffee, or cannot drink as much as they like, due to stomach irritation. Doctors think that chemicals in coffee cause the stomach to overproduce acid. Some coffee drinkers take antacids or drink decaffeinated coffee in an effort to reduce this effect. Others turn to a small but growing number of specialty coffee brews marketed as stomach friendly. (...)