Obesity is a recognized risk factor of gastroesophageal reflux disease (GERD) and esophageal adenocarcinoma. The impact of obesity on the risk of Barrett's esophagus is unclear. This is addressed by a systematic review in this issue of the American Journal of Gastroenterology using additional data given by the authors of individual observational studies. The review suggests that although obesity is a risk factor of Barrett's esophagus, it is probably not a direct effect and is likely to be due to the association with GERD. As obesity is a strong risk factor of esophageal adenocarcinoma, more data are needed in this area. In particular, more research is needed on visceral adipose tissue and risk of esophageal adenocarcinoma, and whether obesity is an important risk factor for the development of neoplasia in those with Barrett's esophagus.