Processed Resistant Starch fiber, taken as supplements, has the opposite effect on stool motility to green Bananas.

In a cluster field trial Bangladeshi rural children, 6-36 months old, were randomly assigned to either a standard care group or a group where mothers were instructed to add cooked green banana to the diets of diarrhoeal children. Through a village-based surveillance system, diarrhoeal morbidity data (severity, duration, compliance) were collected for 14 days. The researchers concluded that a green banana-supplemented diet hastened recovery of acute and prolonged childhood diarrhoea. (1)

In a contrasting study Banana resistant starch (BRS) was extracted to investigate its effects on the gastrointestinal transit, and dejecta of normal and experimentally constipated mice.

Based on the research outcomes, it was found that BRS was able to accelerate the movement of the small intestine in experimentally constipated mice at the dose of 4.0 g/kg body weight per day. In addition, BRS showed the capacity for shortening the time of the first black dejecta at the dose of 2.0 g/kg body weight per day. (2)


  1. Green banana-supplemented diet in the home management of acute and prolonged diarrhoea in children: a community-based trial in rural Bangladesh. Rabbani GH et al, PMID: 20831671
  2. Banana Resistant Starch and Its Effects on Constipation Model Mice. Juan Wang et al, PMC4126267