Ingestion of vegetable salads before rice inhibits the increase in postprandial serum glucose levels in healthy subjects

Abstract

ABSTRACT This study aims to confirm the “vegetable-first” effect. In addition, because we aimed dietary fiber in vegetable salad, the effect after the ingestion of vegetable salad extract (vegetable salad from which solids have been removed) before carbohydrates on postprandial serum glucose level was also evaluated. A total of 13 healthy men were given meals after one-night of fasting: rice–vegetable salad, vegetable salad–rice, and vegetable salad extract–rice. Blood samples were taken at 0, 30, 45, 60, 90, and 120 min after the ingestion of the test meal to measure serum glucose levels. Serum glucose levels were significantly lower after 45 and 60 min in the vegetable salad–rice group compared to the rice–vegetable salad group. No significant difference was found between the vegetable salad extract–rice group and the vegetable salad–rice/rice–vegetable salad group. The result suggested that it might be important to ingest vegetables to obtain the “vegetable-first” effect.