J. Sato, A. Kanazawa, S. Makita, C. Hatae, K. Komiya, T. Shimizu, F. Ikeda, Y. Tamura, T. Ogihara, T. Mita, H. Goto, T. Uchida, T. Miyatsuka, K. Takeno, S. Shimada, C. Ohmura, T. Watanabe, K. Kobayashi, Y. Miura, M. Iwaoka, N. Hirashima, Y. Fujitani, et al. (2017). A randomized controlled trial of 130 g/day low-carbohydrate diet in type 2 diabetes with poor glycemic control. Clinical nutrition (Edinburgh, Scotland), 36(4), 992-1000. https://doi.org/10.1016/j.clnu.2016.07.003

PubMed 27472929

[Abstract]
BACKGROUND & AIMS: The usefulness of low-carbohydrate diet (LCD) for Japanese patients with type 2 diabetes mellitus (T2DM) has not been fully investigated. Therefore, we compared the effectiveness and safety of LCD with calorie restricted diet (CRD).

METHODS: This prospective, randomized, open-label, comparative study included 66 T2DM patients with HbA1c >7.5% even after receiving repeated education programs on CRD. They were randomly allocated to either the 130g/day LCD group (n = 33) or CRD group (n = 33). Patients received personal nutrition education of CRD or LCD for 30 min at baseline, 1, 2, 4, and 6 months. Patients of the CRD group were advised to maintain the intake of calories and balance of macronutrients (28× ideal body weight calories per day). Patients of the LCD group were advised to maintain the intake of 130 g/day carbohydrate without other specific restrictions. Several parameters were assessed at baseline and 6 months after each intervention. The primary endpoint was a change in HbA1c level from baseline to the end of the study.

RESULTS: At baseline, BMI and HbA1c were 26.5 (24.6-30.1) and 8.3 (8.0-9.3), and 26.7 (25.0-30.0) kg/m2 and 8.0 (7.6-8.9) %, in the CRD and LCD, respectively. At the end of the study, HbA1c decreased by -0.65 (-1.53 to -0.10) % in the LCD group, compared with 0.00 (-0.68 to 0.40) % in the CRD group (p < 0.01). Also, the decrease in BMI in the LCD group [-0.58 (-1.51 to -0.16) kg/m2] exceeded that observed in the CRD group (p = 0.03).

CONCLUSIONS: Our study demonstrated that 6-month 130 g/day LCD reduced HbA1c and BMI in poorly controlled Japanese patients with T2DM. LCD is a potentially useful nutrition therapy for Japanese patients who cannot adhere to CRD. This trial was registered at http://www.umin.ac.jp/english/ (University Hospital Medical Information Network: study ID number 000010663).