An obese person runs six times the risk of developing esophageal cancer (cancer of the gullet) compared to people of healthy weight, according to an article that appears in the journal Gut.

The authors explain that rates of esophageal cancer have been rising faster than any other major cancer.

The researchers compared 800 patients with esophageal cancer with nearly 1,600 randomly selected adults who did not have the disease. They found that people under 50 years of age, and men, were the most vulnerable.

The authors write that the association between acid reflux and esophageal cancer is already established. Frequent symptoms of severe heartburn and gastrointestinal reflux disease (GORD) are linked to a significantly raised cancer risk. The greater the frequency of symptoms, the greater are the chances of developing the disease.

A person with GORD has five times the risk of developing esophageal cancer, compared to a healthy person. A person who is obese and experiences frequent acid reflux is 16 times more likely to develop cancer of the gullet.

However, the authors also found that obese people – with a BMI (body mass index) of over 40 – who do not suffer from reflux disease are six times as likely to develop cancer of the gullet, compared to a person with a BMI of between 18.5 and 25.

Even after factors, such as smoking and alcohol consumption were taken into account, the figures still stood. This indicates that obesity is an independent risk factor for cancer of the gullet.

When there are high levels of fat tissue in the body the production of insulin is boosted. This leads to an increase in the amount of insulin-like growth factor in circulation. Both these hormones boost cell growth and reduce cell death – these conditions are ideal for the development of cancers, write the authors.

Fat cells also produce adipocytokines, types of hormones – these accelerate cell growth and are involved in inflammatory processes in the body.

“Combined effects of obesity, acid reflux, and smoking on the risk of adenocarcinomas of the oesophagus”
Gut 2007; doi: 10.1136/gut.2007.131375

Written by: Christian Nordqvist