Postprandial Satiety Responses and Ghrelin Levels With Consumption of White Rice and Brown Rice in Selected Filipino Adults 6

ABSTRACT: Brown (unpolished) rice meals may evoke stronger satiety signals than calorie-matched white (polished) rice meals. This study aimed to compare effects on satiety of brown rice versus white rice using subjective and physiologic measures of satiety in selected Filipino adults. Subjects (n=34) completed a six-week crossover study. In the first two weeks, they were randomly assigned to consume breakfast meals with either brown rice (n=17) or white rice (n=17) matched in energy (~500 kcal) and macronutrient content. This was followed by a two-week washout period and crossover in rice assignments in the next two weeks. One hundred-mm visual analogue scales (VAS) were used to assess hunger and fullness at pre-prandial (0 minutes) and at 15, 30, 45, 60, 90, 120, 150, 180 and 240 min postprandial. Ghrelin levels at 0, 30, 60 and 120 min were determined by radioimmunoassay (RIA). Mean hunger ratings for the brown rice test meals were significantly lower than that of white rice at 150 (p=0.029), 180 (p=0.006) and 240 min (p<0.001) postprandial. Average fullness VAS ratings for the brown rice test meals stayed significantly higher than white rice at 150 (p=0.015), 180 (p=0.003) and 240 min (p<0.001) postprandial. However, temporal profiles of ghrelin did not differ significantly for both types of rice, and did not correlate with hunger and fullness VAS ratings. Subjective measures of satiety did not directly and positively reflect physiologic conditions. The potential health benefits of brown rice are well documented but generalizations about its effect of satiety should be stated with caution. 56

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