Exercise can cut your risk of developing esophageal cancer, according to a survey of existing research. Researchers from the Mayo Clinic have determined that physical activity is associated with a 19 to 32 percent lower risk of developing cancers like esophageal adenocarcinoma. The findings may inspire new prevention strategies in the battle against the disease that kills over 15,000 Americans each year.
The new survey, which was presented at the American College of Gastroenterology's 78th Annual Scientific Meeting in San Diego, Calif., analyzed the results of four previous studies on the subject. The team found that the incidence of esophageal cancer among physically active subjects was significantly lower than that observed among subjects with sedentary lifestyles. Lead researcher Siddarth Singh believes that this underscores the benefits of exercise as well as the lethal health outcomes associated with obesity.
"Obesity has been associated with increased risk of esophageal cancer through high levels of insulin, as well as chronic inflammation,” Singh said in a press release. “By decreasing visceral fat, lowering the level of carcinogenic adipokines, improving insulin sensitivity, and decreasing chronic inflammation, physical activity can potentially decrease risk of esophageal cancer.”
Physicians currently recognize two primary types of esophageal cancer: esophageal adenocarcinoma and esophageal squamous cell carcinoma. Adenocarcinoma usually occurs in mucus-secreting glands in the lower portion of the esophagus. The disease, which is the most common type of esophageal cancer in the U.S., has been associated with obesity in a number of previous studies. Squamous cell carcinoma, on the other hand, begins in the cells lining the middle of the esophagus. Most individuals who develop either type die within a year of diagnosis.
According to Singh, the relationship between physical activity, esophageal cancer, and obesity is also supported by an epidemiological shift.
"The incidence of esophageal squamous cell cancer is declining worldwide, the incidence of esophageal adenocarcinoma has been rapidly rising,” he explained. “This increase may be partly attributable to the obesity epidemic."
That said, the link between exercise and esophageal cancer requires additional research. As current evidence is limited to observational analysis, a causal relationship cannot yet be established. According to Singh, they should not rule out the possibility of a third factor influencing both exercise habits and the risk of esophageal cancer.