Effects of Intake of Puffed wx ae Double Mutant Brown Rice on Human Blood Glucose and Lipid Levels

The amylopectin in waxy amylose-extender (wx ae) double mutant rice characteristically has a small number of branch chains and long side chains. In this study, we conducted single intake trials and middle term intervention trial to puffed non-glutinous Uruchi and wx ae brown rice. Postprandial blood glucose response to a single intake of puffed Uruchi and wx ae brown rice were measured with 3 men and 4 women (47.1 ± 12.7 years of age (mean ± standard deviation [SD])). Subjects who were fasted for 10 to 12 h, has ingested 20 g of the puffed sample. Incremental blood glucose levels of wx ae at 45 and 60 min (p < 0.01), and its peak (30 min) were much lower than for Uruchi. Middle term intervention trial had assigned 14 healthy men and women to eat either puffed brown rice of wx ae or Uruchi for 15 days to compare possible effects on blood glucose and serum lipid levels. Each group consumed 60 g of puffed brown rice a day, at any time of day, in addition to their ordinary meals. Those in the experimental diet (ED) group (4 men and 3 women; 45.1 ± 16.8 years of age) ate wx ae brown rice, while those in the control diet (CD) group (5 men and 2 women; 45.1 ± 15.1 years of age) ate Uruchi rice. Fasting blood samples were obtained before and after the experiment to examine and compare clinical chemical test values. The results showed that 1,5anhydroglucitol (1,5-AG) declined significantly in the CD group and total cholesterol levels declined in the ED group, while triglyceride values rose in the CD group. Thus we expect that wx ae brown rice can be used as a functional food superior to Uruchi brown rice.