Scottish experts claim that restriction around the waist, especially if someone is overweight, can allow stomach acid to move up into the gullet which can cause damage that increases risk of oesophageal cancer.
Doctors from Glasgow and Strathclyde universities and Southern General Hospital recruited 24 healthy volunteers with no history of acid reflux.
Half the volunteers had normal waist sizes while the rest were overweight.
Each was asked to swallow a specially designed probe, which took a range of measurements both before and after each participant had eaten a meal, 'The Daily Record' reported.
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Researchers found that even in healthy volunteers, wearing a tight belt and being overweight caused a partial hiatus hernia and acid reflux.
"Wearing a tight belt, especially if you are overweight, puts strain on the valve between the stomach and the gullet. This causes stomach acid to leak upwards into the gullet," said lead researcher Professor Kenneth McColl, of Glasgow University's institute of cardiovascular and medical sciences.
"Unlike the stomach, which is designed to withstand this, the gullet is damaged by the acid. This causes heartburn and, in the longer term, possibly oesophageal cancer," McColl told the paper.