Objectives: Dietary fiber (DF) supplements improve fecal incontinence (FI). Here, we investigated the effects of dietary guidance without DF supplements in patients with FI.

Methods: This was an interventional study on the nutritional guidance alone by a dietitian where outcomes were compared before and one month after the guidance. In this study, participants attended a one 20-min dietary guidance session and received individual guidance on dietary management according to the 2017 Japanese FI guidelines, between January 2016 and March 2019. The main assessment items used were as follows: (i) the Fecal Incontinence Severity Index (FISI) to assess symptoms, (ii) the Fecal Incontinence Quality of Life Scale (FIQL) to assess the quality of life, and (iii) the dietary intake per day.

Results: Out of 61 patients who participated in this study, 50 (82%) completed the entire study and 29 (48%) continued a self-controlled diet therapy without drug treatment. Of the 50 patients, the FISI and FIQL scores were significantly improved after the guidance (FISI: 19 before vs. 10.5 after, P < 0.001; FIQL: 2.9 before vs. 3.2 after, P < 0.001). There was no statistically significant difference in the overall DF intake before and after the dietary guidance. However, foods containing DF changed significantly after the guidance. The intake of rice was significantly increased, whilst that of fruits, dairy products, and confectioneries was significantly reduced after the guidance.

Conclusions: Individual dietary guidance without DF supplements was effective. These results suggested that increasing rice consumption and restricting some foods had positive effects on improving FI.