Study to Evaluate Dietary Modification in Patients With Functional Dyspepsia.

Functional Dyspepsia (FD) is defined by the Rome III criteria as bothersome postprandial fullness, early satiation, epigastric pain, or epigastric burning in the absence of structural or systemic disease that can explain the symptoms. These symptoms have been present for at least 3 months with symptom onset 6 months prior to the diagnosis. The low fermentable oligo-di-monosaccharides and polyols (FODMAP) diet has been studied in irritable bowel syndrome (IBS) patients and has been shown to have modest benefit in a limited number of small studies. The diet is generally started by complete elimination of fructose, lactose, fructans, galactans, and polyols. Following symptom improvement, these groups are reintroduced one at a time while the patient monitors for symptoms. Although the low FODMAP diet has never been formally studied in patients with functional dyspepsia, we have noted the FD patients report improvement in their symptoms on the diet. This improvement could be explained by reduction in duodenal and gastric distention with the low FODMAP diet or a change in the duodenal flora. To date, there have been no randomized trials evaluating dietary modification in FD. The purpose of this study is to evaluate the efficacy of the low FODMAP diet in functional dyspepsia. The investigator's hypothesis is that the addition of the FODMAP diet to standard medical treatment will result in improved symptom control in patients with functional dyspepsia.