Crossover Study of the Effect of "Vegetables Before Carbohydrates" on Reducing Postprandial Glucose and Insulin in Japanese Subjects with Type 2 Diabetes Mellitus

Abstract

Postprandial hyperglycemia is associated with increased risk for macrovascular disease. We studied the effects of eating "vegetables before carbohydrates" on postprandial plasma glucose in outpatients with type 2 diabetes mellitus (T2DM). We conducted a randomized crossover study in 15 subjects with T2DM patients controlled by diet and having the following profiles age 61.7±11.6 yrs, male/female ratio: 7/8, BMI 24.7±4.3, HbA_1c 6.0±0.6%, years of DM duration 5.3±8.8 yrs: mean±SD. Subjects ate test meals consisting of white rice and vegetable salad, eating either "carbohydrates before vegetables" or vice versa for 4 weeks. Plasma glucose and serum insulin were evaluated at 0, 30, 60, and 120 min after each meal. Postprandial plasma glucose in those following the "vegetables before carbohydrates" regimen was reduced at 30 and 60 min compared to the reverse regimen at 217±40 vs 172±31 mg/dl (P<0.01) and 208±56 vs 187±41 mg/dl (P=0.074). Postprandial serum insulin decreased significantly at 30 and 60 min in the "vegetables before rice" regimen at 32.9±20.8 vs 22.3±14.6 μU/ml (P<0.01), 35.4±21.6 vs 24.9±13.4μU/ml (P<0.05). These results suggest that eating vegetables before carbohydrates may be beneficial in preventing subjects with postprandial hyperglycemia and T2DM.