Dietary instructions focusing on meal-sequence and nutritional balance for prediabetes subjects: An exploratory, cluster-randomized, prospective, open-label, clinical trial

Abstract Background Although lifestyle modifications are known to be effective in type 2 diabetes (T2D) as well as in prediabetes, adherence to a healthy diet is difficult for some, and interventions of lifestyle modifications need to be revised occasionally. Meal sequence has been gaining attention as a part of a healthy diet among T2D individuals to improve glycemia and body weight. In addition, a dietary instruction program, SMART Washoku®, which can help individuals to consume a more nutritionally balanced diet, has been developed. Methods The current exploratory trial was designed to examine the effects of dietary instructions focusing on meal sequence and nutritional balance in individuals with prediabetes in the Japanese national health check-up and guidance program. Participants were cluster-randomized into three groups: Group A, receiving a conventional health guidance program (n = 11); Group B, receiving health guidance with dietary instructions focusing on meal sequence (n = 18); and Group C, receiving health guidance with dietary instructions focusing on nutritional balance (n = 13). Participants received health guidance education and various measurements before and 6 months after the instructions. Results Body weight in Group B was significantly reduced compared to that in Group A, with similar adherence, while the effects on glycemia were similar between the two Groups. Body weight reduction was greater in Group C compared to that in Group A, although adherence in Group C was significantly lower than that in Group A. Conclusion The group receiving health guidance with dietary instructions focusing on meal sequence exhibited similar adherence and greater reduction in body weight than the group receiving conventional health guidance.