Abstract
Carbohydrate foods, which produce low glycemic responses, have been shown to be beneficial
in the dietary management of chronic diseases such as diabetes and hyperlipidemia. This study
determined the starch digestion rate in vitro and, in a randomised crossover design, the
postprandial blood glucose response of 10 healthy and nine type 2 diabetic volunteers to brown
rice compared to milled rice from the same batch and variety. The total sugar released in vitro
was 23.7% lower in brown rice than in milled rice. In healthy volunteers, the glycemic area and
glycemic index were, respectively, 19.8% and 12.1% lower (pB/0.05) in brown rice than milled
rice, while in diabetics, the respective values were 35.2% and 35.6% lower. The effect was partly
due to the higher amounts of phytic acid, polyphenols, dietary fiber and oil in brown compared
to milled rice and the difference in some physicochemical properties of the rice samples such as
minimum cooking time and degree of gelatinisation. In conclusion, brown rice is a more health
beneficial food for diabetics and hyperglycemic individuals than milled rice.