We read with great interest the article “Roux en Y Gastric Bypass Increases Ethanol Intake in the Rat” [1] from Jon Davis and colleagues, published online in the Obesity Surgery on February 26, 2013. This study reports an impressive data set showing increased alcohol consumption in an outbred rat strain after Roux-en-Y gastric bypass surgery (RYGB), a finding that has potential important clinical implications. This study supports recent clinical investigations showing increased susceptibility to alcohol abuse following RYGB [2–5] and corroborates our recent studies that reported increased alcohol taking and increased motivation to work for alcohol reward in dietary obese rats that received RYGB [6, 7].

However, we were surprised that the authors did not refer to prior publications showing similar outcomes [6, 7], which would have strengthen the conclusion of their paper. The authors also failed to cite their prior paper [8], which reported decreases in alcohol intake after RYGB in alcohol-preferring rats as well as decreased alcohol intake after RYGB in patients who regularly drank alcohol prior to undergoing surgery. The differences between their current results and their prior findings suggest that the effects of RYGB may be modulated by genetic background and should have been discussed rather than ignored.

There are increasing concerns over the lack of reproducibility of findings from preclinical research [9], yet the study of Davis et al. show similar findings to the ones we previously reported using a similar animal model and surgical procedure but done by an independent laboratory.