Physical activity is associated with a reduced risk of esophageal cancer, according to a new study presented by Mayo Clinic researchers at the American College of Gastroenterology's Annual Scientific Meeting, Oct. 11-16, in San Diego.
Esophageal cancer is the sixth most common cancer in men worldwide. Early detection and prevention are critical to survival because most patients do not survive the first year of diagnosis, and only 15 percent of patients survive more than five years.
In an analysis of four studies, researchers observed a 32 percent lower risk of esophageal adenocarcinoma in people who were physically active. The analysis also showed the overall risk of esophageal cancer was 19 percent lower among the most physically active people, compared with the least physically active.
"Although the incidence of esophageal squamous cell cancer is declining worldwide, the incidence of esophageal adenocarcinoma has been rapidly rising. This increase may be partly attributable to the obesity epidemic," says Siddharth Singh, M.B.B.S., the study's lead author and researcher at Mayo Clinic.
"Obesity has been associated with increased risk of esophageal cancer through high levels of insulin, as well as chronic inflammation. By decreasing visceral fat, lowering levels of certain carcinogens, improving insulin sensitivity and decreasing chronic inflammation, physical activity can potentially decrease risk of esophageal cancer," says senior study author Prasad Iyer, M.D., a Mayo Clinic gastroenterologist.
There are two types of esophageal cancer: esophageal squamous cell, which begins in cells lining the esophagus, and adenocarcinoma, which begins in cells that make and release mucus and other fluids. Barrett's esophagus, a complication of long-term acid reflux disease, is a risk factor esophageal adenocarcinoma.