[Problem] To provide: an agent for increasing intestinal butyric acid which is capable of effectively increasing intestinal butyric acid; a food composition for increasing intestinal butyric acid; a proliferation agent for butyric acid-producing bacteria; a food composition for proliferating butyric acid-producing bacteria; a method for increasing intestinal butyric acid; a method for proliferating butyric acid-producing bacteria; a method for treating or preventing intestinal inflammation, fatty liver, diabetes, colorectal cancer or obesity using the same; and use of 1-kestose for producing a pharmaceutical preparation for treatment or prevention of these diseases. [Solution] An agent for increasing intestinal butyric acid and a proliferation agent for butyric acid-producing bacteria, each comprising 1-kestose as an active ingredient. According to the present invention, intestinal butyric acid in humans or animals can be easily and effectively increased with little side effects or safety concerns. According to the present invention, furthermore, intestinal inflammation, fatty liver, diabetes, colorectal cancer or obesity can be prevented or treated by increasing intestinal butyric acid in humans or animals.