Coffee Sensitivity

I've always had a problem with coffee - in recent years, Ive put it down to an intolerance, added to the ever increasing list if foods my stomach is sensitive to.
I recently mentioned to someone that I seem to have more of a problem with instant coffee than with freshly brewed coffee. They suggested that it might have something to do with the acid in the coffee.
I guess I'd never thought of coffee being acidic before. (Now that's got me thinking about all the other acidic things I should probably avoid!)
Anyway, there was a piece in the paper this morning that seemed to prove my theory.
The scientists at the University of Vienna say that they have found the components that cause heartburn and stomach pain in coffee.

In an article I found online, it says of the study;
"Doctors think that chemicals in coffee cause the stomach to overproduce acid, while some coffee drinkers take antacids or drink decaffeinated coffee in an effort to reduce this effect, while others turn to a small but growing number of specialty coffee brews marketed as stomach friendly.
The scientists unexpectedly found that one of the coffee components, N-methylpyridium (NMP), seems to block the ability of the stomach cells to produce hydrochloric acid and could provide a way to reduce or avoid stomach irritation.
Since NMP is generated only upon roasting and not found in raw coffee beans, darker-roasted coffees contain higher amounts of this stomach-friendly coffee ingredient. "
It all makes perfect sense to me!