A Comparison Of Diets Enriched With Purified Resistant Starch Or Resistant Starch In The Form Of Whole-Grain Flour In Goto-Kakizaki (Gk) Rats

GK rats are a non‐obese type 2 diabetes model. In a previous study, GK rats had increased insulin sensitivity in response to dietary purified high‐amylose maize (HAM) resistant starch (RS). The aim of this study was to compare the purified starch with resistant starch in the form of whole‐grain flour. GK rats were put in four diet groups (n=12 per group) by equivalent homeostatic model assessment for insulin resistance (HOMA‐IR) and body weight: (1) control starch with no WG or RS [CON], (2) purified HAMRS [RS], (3) WG waxy corn flour with low RS [WG], and (4) WG HAMRS flour [WG+RS]. Each of these was fed for 12 weeks. Rats fed RS and WG+RS had lower fasted HOMA‐IR (more insulin sensitive) and higher (fed state) GLP‐1 active than WG and CON measured during the study. For euthanasia rats were fasted. There were larger empty ceca and greater short‐chain fatty acids in cecal contents for RS and WG+RS compared to CON and WG; but the values for RS were greater than WG+RS. RS, WG+RS, and WG had lower cecal contents pH and lower abdominal fat/body weight than CON. In summary, presence of RS increases fermentation and results with WG indicate some benefits independent of RS content. Funding: Ingredion and LSU AgCenter.