This study aimed to determine whether educating diabetic patients to 'eat vegetables before carbohydrate' was as effective on long-term glycemic control as a traditional exchange-based meal plan. To test this hypothesis, we carried out a randomized, controlled trial in patients with type 2 diabetes that compared changes in HbA1c as the primary outcome. A total of 101 patients were stratified according to sex, age, BMI, duration of diabetes, and HbA1c, and then randomized to receive instructions to eat either vegetables before carbohydrate (VBC, n=69) or an exchange-based meal plan (EXB, n=32). The impact of the two plans on glycemic control was compared over 24 months of follow-up. Significant improvements in HbA1c over 24 months were observed in both groups (VBC, 8.3 to 6.8% vs EXB, 8.2 to 7.3%). HbA1c levels were significantly lower in the VBC group than in the EXB group after 6, 9, 12 and 24 months of the study. Both groups exhibited similar improvements in dietary practices with respect to intake of carbohydrate, fats and sweets, while the VBC group had a significant increase in consumption of green vegetables and a significant decrease in fruit consumption. A simple meal plan of 'eating vegetables before carbohydrate' achieved better glycemic control than an exchange-based meal plan in Japanese patients with type 2 diabetes over a 24-month period.