Experts believe wearing a belt can force acid into the oesophagus, damaging the cells and increasing the risk of throat cancer.
They found people who are overweight and wear belts are more at risk.
The researchers, from Glasgow and Strathclyde Universities and The Southern General Hospital in Glasgow, tested 24 people with no history of acid reflux.
They asked them to swallow a probe, which took measurements before and after each person had eaten a meal.
Half of the participants were normal waist sizes and the other overweight and readings were taken when they had a belt on and off.
They found that even in healthy people, wearing a tight belt caused a partial hiatus hernia, which makes acid reflux more likely. A hiatus hernia happens when part of the stomach squeezes into the chest through an opening in the diaphragm, which can in turn cause acid to leak into the oesophagus.
This is linked to cancer because the acid pushed up into the gullet by wearing a belt can damage cells in the oesophagus, causing them to change.
They also found this was more pronounced in those who were overweight.
Lead researcher Professor Kenneth McColl, of Glasgow University’s institute of cardiovascular and medical sciences, told the Daily Record: “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.
”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.”
The findings were reported in the British Medical Journal Gut. Researchers said they were concerned as oesophageal cancer is one of the most rapidly increasing forms of the disease in the world.
Cancer of the oesophagus is fairly rare in the UK, with around 8,200 people diagnosed every year. But the number of people with the disease has almost doubled in 30 years, with the rise being linked to obesity and acid reflux.
Researchers recently found that frequent bouts of heartburn cold be an early warning of throat cancer, with gastric reflux linked to a 78 per cent increased risk of developing the disease. Taking antacids was found to reduce this risk by 41 per cent.
Early symptoms of oesophageal cancer are often dismissed as heartburn leading to late diagnosis and a short life expectancy for patients – most only living three months with the disease.
Cancer Research UK said only 13 per cent of those diagnosed with oesophageal cancer live five years or more, and urge anyone with heartburn symptoms to go to their doctor.
Recent scientific developments of a camera in a capsule that can be swallowed have raised hopes that it could be used to spot early signs of the disease. Sensors can detect cell changes associated with Barrett's oesophagus, a precancerous condition.
The World Cancer Fund estimates more than 22,000 cases of cancer could be prevented every year in Britain if people kept to a healthy weight.