From butterflies in your stomach before giving a big speech at work to an ulcer that acts up whenever things get tough, our gastrointestinal health seems to be intimately connected to our emotions. Gastroesophageal reflux disease (GERD) or acid reflux is no exception, and heartburn symptoms can escalate right along with your workload.

However, the relationship between stress and heartburn is a tricky one; just as one man's stress is another's adrenalin rush, stress may sock in the gut some—but not all—people who have GERD.

And although stress may exacerbate GERD symptoms, it's unlikely to be the underlying cause of your chronic heartburn. In the past, stress was thought to be the culprit in a variety of gastrointestinal problems, including ulcers and inflammatory bowel diseases such as Crohn's disease. Now it's known that bacterial infections (in the case of ulcers) and underlying inflammation (in bowel diseases) are to blame, not stress.

Stomach acid may rise, but not everyone feels the burn
Even if excess weight, smoking, alcohol, or other GERD-triggering factors are the underlying cause of your heartburn, stress can make you feel the symptoms of acid reflux more acutely.

"Stress can affect many gut functions, and we know that patients who are under a lot of psychological stress suffer from more severe reflux symptoms—without necessarily having more severe reflux," says Mitchell Cappell, MD, PhD, the chief of gastroenterology at Beaumont Hospital in Royal Oak, Mich. "We live in stressful times and heartburn is incredibly common," he says.

In surveys, the majority of people who experience acid reflux identify stress as a common trigger. The problem is that studies have failed to find a connection between the stress and the amount of stomach acid in the esophagus, which is the ultimate cause of heartburn pain. One explanation for this discrepancy is that stress may cause what's known as "hypervigilance." In other words, stressed people become more sensitive to and have a greater awareness of physical symptoms that may not bother them if they weren't stressed.

In a 2005 study in the Journal of Psychosomatic Research, researchers measured the esophageal acid levels in more than 40 patients who had chronic heartburn and acid reflux. While the measurement was taking place, the researchers induced stress in half of the participants by requiring them to prepare and deliver a five-minute speech. The acid levels in both groups were nearly identical; patients in the "stressed" group, however, reported more intense acid reflux symptoms, suggesting that their sensitivity to their symptoms had been heightened.

Findings such as this don't necessarily mean that stress-related reflux is "all in your head." Some experts suggest that stress may excite areas of the brain that in turn make pain receptors in the esophagus more active. So acid levels may not rise that much more in stressed people than carefree ones, but each drop of acid may become that much more painful.

In addition, it's known that people who are stressed can have a drop in levels of hormone-like substances known as prostaglandins, which can help coat the lining of the stomach and protect it from acid, says Jonathan Schreiber, MD, a gastroenterologist at Mercy Medical Center in Baltimore. "Once you are under stress, prostaglandin levels go down." Certain drugs block the production of prostaglandins, including anti-inflammatory drugs such as ibuprofen and naproxen, which is why this common class of drug is often a cause of stomach problems, including nausea and ulcers.

The bottom line? "There is a strong connection between stress and acid reflux," says Dr. Schreiber. No matter how the body and mind senses them, GERD symptoms are equally real.