High-amylose maize resistant starch type 2 (HAM-RS2) intake, body composition, and satiety in overweight adults

The purpose of this dissertation determined the impact of high-amylose maize resistant starch type 2 (HAM-RS2) consumption on objective and subjective satiety and body composition changes in overweight adults. Twenty adults (17 female , 3 male) aged (mean +/- SEM) 30.3 +/- 9.9 years with a BMI of 34.5 +/- 6.3 consumed muffins with 30 g HAM-RS2 or digestible starch (placebo) daily for six weeks using a randomized, placebo-controlled study design. No significant difference in overall likeability resulted between HAM-RS2 and placebo muffins based on sensory analysis. Data was collected at baseline and week six. Objective satiety was determined by plasma glucagon-like peptide-1 (GLP-1), peptide YY (PYY), cholecystokinin (CCK), and leptin. A visual analogue scale (VAS) tool measured subjective satiety. Body composition was analyzed by anthropometrics and dual-energy x-ray absorptiometry (DXA). Non-parametric and Pearson's correlation tests examined between- and within-group changes. No significant change in plasma objective satiety, subjective satiety, or body composition occurred between groups although within-group differences were found. After HAM-RS2 consumption an increase in iAUC GLP-1 ( P = 0.041) and fasting PYY (P = 0.023) resulted, while iAUC leptin (P = 0.012) decreased. A reduction in iAUC glucose occurred in both HAM-RS2 (P = 0.034) and placebo (P = 0.018) groups without concurrent significant changes in insulin or insulin sensitivity, although a pattern toward improved insulin sensitivity was found in the HAM-RS2 group. A favorable alteration in body composition patterns conducive for chronic disease reduction ensued in the HAM-RS2 group demonstrated by the following changes: 3.51 +/- 1.54 cm in hip circumference (P = 0.033), -0.03 +/- 0.01 in waist-to-hip ratio (P = 0.019), and -1.88 +/- 0.86 kg (P = 0.046) in lean trunk mass. Within-group improvements of 24.2% and 0.6% in mean subjective satiety occurred in the HAM-RS2 and placebo groups, respectively, but significance was not achieved. Subjective satiety did not correlate with GLP-1, PYY, or leptin concentrations. Daily consumption of 30 g HAM-RS2 impacted GLP-1, fasting PYY, glucose, and body composition patterns in participating overweight adults, which may reduce the risk of chronic disease.