Pelvic radiotherapy affects up to 300,000 patients/y world-wide. The subsequent change in bowel habits affects QoL in 5 of 10 patients , and complications may appear in 1 of 10 to 1 of 20 patients 10 y after radiotherapy . Information on adequate symptom modulation treatments is scant, and clinical research on late toxicity has not been a priority. Although a significant proportion of patients may improve with specialized nutritional intervention , patients are seldom referred to a specialized dietitian. In our study, permanent flatulence, abdominal disten-sion, and/or diarrhea were always significantly worse in patients in groups 3 and 2, whereas patients in group 1 had the lowest symptom severity. The current study showed that the nutritional content of each patient’s diet based on regular foods with ap-propriate education and manipulation was key in improving gastrointestinal function and acute symptoms during radiother-apy and was sustained in the long term beyond the period of nutritional counseling. Dietary modifica-tions may indeed alter bowel functions, such as motility, enzyme secretion, and nutrient absorption . Nutrition modulates the gastrointestinal flora, the ecology of which is central to the pathogenesis of radiation injury and its severity. Awell-balanced gut flora modulated by adequate foods may thus protect against injury and late radiotherapy toxicity