Background: Diabetes patients need to improve postprandial hyperglycemia. Eating slowly is effective for improving postprandial glucose (PPG), and a simple method is required in daily life. This study aimed to determine the effect of improving PPG by eating with the non-dominant hand in Japanese patients with type 2 diabetes (T2D).

Methods: This was a prospective, non-randomized, open-labeled, single-arm study that enrolled 10 patients of T2D who hospitalized in Asama General hospital for glycemic control. We measured glucose levels, C-peptide concentrations, and eating styles when subjects ate with the dominant hand and the non-dominant hand. Chopsticks were used for meals. The mean daily intake of energy, carbohydrate, protein, and fat was set individually and was unchanged during the period of this study. Participants were instructed to eat vegetables fast and carbohydrates last, and to chew 30 times per bite.

Results: Subjects (5F/5M) were average age 54 years, BMI 26 kg/m2, HbA1c 8.6%, of which 7 used only oral hypoglycemic drugs and 3 used injections. Each PPG and PPG AUC decreased with the non-dominant hand compared to the dominant hand, especially at breakfast (p<0.001) and dinner (p=0.015). Delta PPG and delta C-peptide of breakfast were 76 mg/dl and 3.4 ng/ml for the dominant hand, and 39 mg/dl and 2.4 ng/ml for the non-dominant hand, both of which were significantly lower in the non-dominant hand (PPG p=0.002, C-peptide p=0.015). Each meal time was significantly extended from the dominant hand to the non-dominant hand (breakfast time 18 vs. 23, lunch 18 vs. 24, dinner 18 vs. 27 minutes, p<0.01), and the number of chewing per bite at breakfast significantly increased (22 vs. 30 times/bite, p<0.001).

Conclusions: Our findings suggested that eating with the non-dominant hand was effective in improving PPG in Japanese patients with T2D by prolonging the meal time and increasing the number of chewing per bite.


E. Nishimori: None. M. Naka: None.

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