著者

林 宏紀 山下 貴宏 吉田 和敬 砂堀 諭 菅沼 大行

出版者

一般社団法人 日本食育学会

雑誌

日本食育学会誌 (ISSN:18824773)

巻号頁・発行日

vol.12, no.4, pp.303-312, 2018

---

<p>We have reported that ingesting vegetable juices before meals might control postprandial blood glucose level for the prevention of diabetes. In this study, two human intervention studies were conducted under the hypothesis that sugar contained in vegetable juices was greatly involved in its action. Firstly, a 200mL of vegetable juice (①), vegetable and fruit mixed juice (②) or a sugar solution consisting of the same composition and concentration as ② (③) was served 30 minutes prior eating rice and compared the effect of each beverage on postprandial blood glucose with that by the same amount of water. As a result, intake of ② and ③ significantly suppressed the elevation in postprandial blood glucose level. In subjects with the top 50% maximum postprandial blood glucose level after ingesting water, the same effect was also observed by ingestion of ①. These results suggested that the suppressive effects of pre-meal ingestion of ① and ② were elicited via induction of insulin by the sugar in the beverages.</p><p>Next, we evaluated the changes in blood glucose and blood insulin concentrations after ingestion①, ②, ③ and a sucrose solution (④, sucrose water) with the same sugar concentration as in ③. As a result, Tmax, the time showing the highest concentration, of blood glucose level was significantly later in ① and ② than in ③ and ④, and Tmax of insulin was significantly later in ① than in ② and ③. We assumed that dietary fiber and/or other substances contained in ① and ② moderate the absorption of sugar, and presumed that the differences observed in this study affected the difference in the effects in the first intervention study. In addition, in the intake of ④, the Tmax of the blood glucose level was significantly faster than that of ① and ②, and Cmax, maximum concentration, of insulin was significantly larger than that of ①. This supposed that frequent ingestion of sugar water was considered to be a higher risk of diabetes than vegetable juices and vegetable fruit mixed juices containing the same amount of sugar.</p><p>As described above, the suppressive effect on the elevation in postprandial blood glucose level by the vegetable juice and vegetable fruit mix juice may be primarily due to the carbohydrates contained in these drinks, and the composition and concentration of carbohydrates might regulate the timing and strength of insulin induction and affect the effect.</p>