Opera singers are more likely to suffer from heartburn and other symptoms of stomach acid reflux than other people, say researchers.

Writing in the journal Gastroenterology, Dr Giovanni Cammarota, from the Catholic University of Medicine and Surgery in Rome, Italy, and team explain that opera singers perform singing tasks that require straining and deep intakes of breath, which cause rapid changes in pressure within the chest area and above the stomach.

"These mechanisms, repeated several times per day and over many years of professional activity, could, in theory, increase the occurrence of reflux symptoms," they say.

To investigate, the researchers studied 351 professional opera choristers from well-known choirs in various Italian regions and 578 other people of similar age from the same areas.

After taking into account each participant's age, body mass index, smoking habits and alcohol consumption, the team found that the opera singers were 1.6 times more likely to suffer from heartburn and 1.8 times more likely to experience regurgitation than the other participants.

The singers were also 1.4 times more likely to have a regular cough and nearly 2.5 times more likely to suffer from a hoarse voice.

The choristers' lifetime duration of singing activity was significantly associated with their risk of regular regurgitation episodes.

"The reported prevalence of typical reflux symptoms, such as heartburn and regurgitation, but also cough and hoarseness, was significantly higher in opera choristers than in the sample of the general population," the researchers summarise.

They add that "because a long duration of [acid reflux] might compromise the continuation of the artistic career of choristers by negatively interfering with their professional performances", further studies should be conducted to see whether such symptoms are stress-induced "and, therefore, represent a work-related disease".