Introduction. The high incidence of lactose intolerance leads us to consider that many of our patients could suffer from this alteration. Therefore, as its main sign (even when asymptomatic) is increased intestinal gas, patients recovering from a Nissen fundoplication have a significant probability of suffering from gas bloat syndrome. Materials and Methods. This prospective study was conducted from November 2012 to January 2017, we included all the patients who had been treated by the Nissen technique for gastroesophageal reflux disease with gas bloat syndrome detected during follow-up and tested positive for lactose intolerance. The study participants were then prescribed a lactose-poor diet to be followed for 3 months. The patients were asked to complete quality of life and symptomatology questionnaires before and after diet. The pre- and post-diet results were then compared. Results. The pre- and post-diet results showed statistically significant improvements in both questionnaires. Conclusion. Lactose intolerance may account for the symptoms presented by a significant number of patients with gas bloat syndrome following antireflux surgery; these patients could benefit from consuming a lactose-free diet, which we expect to alleviate or, in some cases, eliminate the above symptoms.