Konjac acts as a natural laxative by increasing stool bulk and improving colonic ecology in healthy adults.

Objective: Konjac glucomannan (KGM) has been shown to relieve constipation, which could be associated with increased stool bulk and improved colonic ecology.

Methods: This placebo-controlled study consisted of a 21-d placebo period, a 7-d adaptation period when volunteers consumed KGM progressively, and a 21-d KGM-supplemented period (1.5 g/meal, 4.