Galactooligosaccharide supplementation reduces stress‐induced gastrointestinal dysfunction and days of cold or flu: a randomized, double‐blind, controlled trial in healthy undergraduate students

Abstract

Acute psychological stress is associated with dysregulated gastrointestinal (GI) and immune function. We examined whether galactooligosaccharides (GOS) supplementation reduced GI dysfunction and percentage of days of cold/flu in academically stressed students. Subjects (n=427) received 0 g, 2.5 g, or 5 g GOS for 8 wk around fall final exams. Level of stress and cold/flu symptoms and intensity (SI) were recorded daily. The SI from 9 cold/flu symptoms was summed for an SI score with a day of cold/flu defined as a sum >6. The GI Symptom Response Scale score was completed weekly. Stress was positively related to diarrhea, indigestion, and reflux syndromes, abdominal pain, average daily cold/flu SI score, and percentage of days with cold/flu. GI symptom scores were lower with GOS for diarrhea, constipation, abdominal pain, and indigestion syndrome. The cold/flu SI score was affected by GOS treatment and level of stress (P<0.0001); 2.5 g of GOS was consistently associated with a lower SI score but 5 g was only protective at lower levels of stress. Percentage of cold/flu days was associated with GOS treatment within different BMI categories (P=0.0002). In healthy weight individuals, we observed a 40% reduction with 5 g GOS. Acute psychological stress was directly related to symptoms of GI dysfunction and cold/flu. GOS supplementation attenuated these symptoms and days of cold/flu. Supported by Corn Products International Grant Funding Source: Corn Products International