[Obesity, metabolic syndrome].

The prevalence of reflux esophagitis was low in Japan but has increased in recent years. This increase might be due to the increase in the elderly population and obesity with west- ernized diets. Obesity and the metabolic syndrome cause reflux esophagitis. Increase in central obesity induces inflammation in fat tissue. Moreover, insulin resistance induces hypertension, hypertriglyceridemia and impaired glucose tolerance, and causes the metabolic syndrome. Anti-hypertensive drugs (calcium channel blockers, etc.) and hyperglycemia might cause an esophageal movement disorder. Inflammatory state and change of esophageal move- ment might cause and worsen reflux esophagitis. The metabolic syndrome, characterized by central obesity, is a risk factor for reflux esophagitis. It is necessary to consider lifestyle improvements and medications to decrease weight and central obesity.