Rice-based Korean meals (bibimbap and kimbap) have lower glycemic responses and postprandial-triglyceride effects than energy-matched Western meals

Background The rate of metabolic syndrome (MetS) is exceptionally high in Korea, and the health risks and dietary implications of MetS have been reported extensively. Although most meals include combination foods, little is known about metabolic responses to meals containing various foods (such as a hamburger, which typically includes meat, bread, and vegetables). The purpose of this study was to compare glycemic responses and postprandial-triglyceride (PTG) concentrations after consuming each of four test meals: bibimbap, kimbap, pork cutlet, and hamburger. Methods A clinical trial was carried out with 32 men using an open 4 × 4 × 4 treatment, sequence, and period crossover design. The blood-glucose concentrations, incremental area under the curve (iAUC), glycemic index (GI), insulinogenic index, and PTG after each test meal were determined. Results The iAUC_2h and C_max responses were proportional to the amount of carbohydrates in the experimental diets [i.e., higher (p < 0.001) in bibimbap and kimbap than in pork cutlet and hamburger diets]; however, no differences were observed in the GI response among the experimental diets. The high-MetS-risk group had increased 4-hour PTG after consumption of pork cutlet and hamburger (p < 0.001) compared to the Korean meals, although the GI did not differ significantly by meal in the high-MetS-risk group. The consumption of bibimbap and kimbap meals, which contain high amounts of rice, was not associated with elevated PTG concentrations. By contrast, the glycemic response and PTG concentrations did increase with consumption of Western-style meals. Furthermore, the PTG concentrations were even more elevated in individuals with MetS risks who consumed Western-style meals. Conclusion We confirmed that Korean-style meals (bibimbap) lowered the risk of metabolic diseases in participants with and without MetS. Despite the high-carbohydrate content in Korean meals, the GI and insulinogenic-index responses did not differ among the diet groups. The lower PTG in Korean diet groups may suggest a beneficial effect in lowering the risk of many other diet-related chronic diseases.