This single-blinded clinical study was designed to determine if a diet consisting of foods having low glycemic indices (GI), with an emphasis on reduction of simple sugars, is an effective tool for reducing symptoms of endometriosis. Chronic inflammation may be the primary activator of endometrial tissue migration and adhesion. Studies suggest that the high levels of sugar (i.e. USDA reports 150 lbs per person a year) promote chronic inflammation. Thus, it was proposed that if there was a reduction in dietary simple sugars (i.e. low glycemic index/load), there would be a concomitant reduction in the painful symptoms of endometriosis. All subjects received healthy dietary guidance according the United States Department of Agriculture (USDA) food pyramid. The experimental group was asked to eliminate all simple sugars throughout the study.There were no statistically significant differences in the mean Endometriosis Symptom Scores (ESS) or Glycemic Indices between the control and test groups. However, the subjects (n=9) who followed through with the trial for the entire six weeks (C=Continuers), maintained higher mean compliance scores, with intermediate Glycemic Load (GL) values, and experienced a significant decrease in endometriosis induced pain as evidenced by the substantial drop in their ESS values, compared to those who dropped out of the study (n=4). This preliminary study did not show a significant difference in the mean glycemic indices (GI) between the Control vs. Test groups. However, the mean GL was significantly lower in the Continuers than in the Dropouts. Acknowledging the fragility of reproducible results due to the small sample size, the data shows that lowering the GL of the diet reduced pain in subjects with endometriosis.