Postprandial Glycemic Responses to Rice Porridge Versus Cooked Rice in Healthy Young Adults: A Randomized Controlled Crossover Study

Background: For individuals with dysphagia, rice porridge (RP) is a standard staple. However, its effect on postprandial glycemia compared to cooked rice (CR) - even with matched carbohydrate content - remains unclear. This study aimed to evaluate the impact of food form (CR vs. RP) on interstitial fluid glucose (IFG) levels using flash glucose monitoring (FGM). Methods: A randomized crossover study was conducted with 31 healthy university students (mean age 20.3 years). Subjects consumed either CR or RP, both standardized to 40.7 g of carbohydrates. IFG was measured using the FreeStyle Libre flash glucose monitoring system (Abbott Diabetes Care, Alameda, CA, USA) every 15 minutes for 120 minutes post-ingestion. Mastication was limited to 10 strokes per mouthful to simulate impaired oral processing. Primary outcomes were the incremental area under the curve (iAUC0-120) and time-specific IFG levels. Results: Compared to CR, RP showed significantly higher IFG levels at 30, 45, and 60 minutes post-ingestion (p < 0.01). The iAUC was significantly greater for RP across all time intervals (0-30, 0-60, 0-90, and 0-120 min) (p < 0.05). No significant difference was observed in subjective fullness (Visual Analogue Scale (VAS)) at 120 minutes (p = 0.1). Conclusions: In healthy young adults, RP induces a more rapid and higher postprandial glucose response than CR despite identical carbohydrate content. This suggests that the increased surface area and gelatinization in porridge facilitate starch hydrolysis. Clinical nutritional management for patients requiring texture-modified diets should account for these glycemic differences.