The results are based on a comparison of almost 800 people with oesophageal cancer and almost 1600 randomly selected people eligible to vote, who did not have the disease.
The findings showed that men, and those under the age of 50 were especially vulnerable.
It is known that acid reflux is linked with gullet cancer and repeated symptoms of severe heartburn or gastrointestinal reflux disease (GORD) were correlated with a much higher risk of the cancer. And the more frequent the symptoms, the greater was the likelihood of having oesophageal cancer.
GORD was found to quintuple the risk of oesophageal cancer, and a blend of obesity and acid reflux boosted the chances of having it by a factor of 16.
But people who were clinically obese had a much higher risk of oesophageal cancer than those whose weight was in the healthy range, regardless of whether they had reflux disease or not.
Therefore, people with a body mass index (BMI) of 40 or more were six times as likely to have the cancer as those with a BMI between 18.5 and 25.
The results of the research held true even after taking account of other factors such as smoking and high alcohol consumption known to be implicated in the disease.
The researchers concluded from the study that obesity is an independent risk factor for the disease.
They said that elevated levels of fat tissue in the body boost insulin production, which in turn increases the amount of circulating insulin-like growth factor.
The authors said that both these hormones stimulate cell growth and curb cell death, conditions which favour the development of cancers.
They further added that fat cells also produce other hormones, collectively known as adipocytokines, which speed up cell growth and are involved in inflammatory processes in the body.
The new study is published in the journal Gut.