Increase in digestive organs of rats due to the ingestion of dietary fiber with similar solubility to that of common bean

The aim of the present work is to study the effect of dietary dietary fiber of similar solubility to that of the cooked common bean in the increase of the small intestine, liver, and pancreas of rats. Recently weaned male Wistar rats were fed ad libitum balanced diets containing cooked common bean (12.9% of dietary fiber plus resistant starch) or casein with 5.0% (control group), 10.0%, 12.5% or 15.0% of dietary fiber plus resistant starch added, with the same proportions of insoluble and soluble fibers and resistant starch found in bean (8:3:1) for 14 days. Weight gain and diet intake were smaller in the group fed the cooked bean diet. However, this group showed the highest increase in the studied organs. Rats that ingested the diet containing casein with 15.0% of dietary fiber added showed a growth of 21.4% in the pancreas. Rats fed other casein diets did not show significant differences (p > 0.05). The diet containing the cooked common bean led to weight gain of all studied organs (50.0% in the pancreas, 25.0% in the liver and 33.4% in the small intestine) and an increase of 47.1% in the small intestine length. Therefore, dietary fiber plus resistant starch had a trophic effect on digestive organs, although they were not the only stimulation factor, because the cooked bean has other chemical components, like phytates and tannins, that probably contribute to that effect.