Objective: To study the short-term effect of resistant starch (RS) from retrograded high-amylose corn starch (HACS) on the excretion of bile acids and nutrients from the small bowel in humans.
Design: Seven healthy ileostomists were given a controlled, constant diet during three days. On days 2 and 3, 100 g/d of one of two test-products—drum-dried ordinary corn starch and autoclaved retrograded HACS, providing 5 and 39 g RS/d, respectively—was given, in random order. Ileostomy effluents were collected for 24 h per day and analysed for wet weight, dry weight, energy, bile acids and nutrients.
Settings: In-patient study at the metabolic ward, Department of Clinical Nutrition, Sahlgrenska University Hospital, Göteborg.
Results: Consumption of retrograded HACS caused (1) a 42% lower mean excretion of cholic acid (P=0.024); (2) a 42% lower mean wet weight concentration of bile acids (P<0.001); (3) a 70% increased excretion of dry weight (P=0.001); and (4) a 41% increased excretion of energy (P=0.036) compared with consumption of drum-dried ordinary corn starch.
Conclusion: The reduced ileal excretion and concentration of cholic acid would be protective regarding colon cancer risk in addition to the increased fermentation substrate provided by RS and other energy-yielding components.
Sponsorship: This work was supported by the Swedish Council for Forestry and Agricultural Research, the Swedish Cancer Foundation, the Swedish Nutrition Foundation and the Göteborg Medical Society.