A randomized controlled clinical trial found superior results in diabetes with a moderate low-carb diet, judging from weight loss and hemoglobin A1c.
I don’t know how many carbs the typical Japanese person eats in a day. In the U.S., it’s 250-300 grams. Here’s how the study at hand was done:
“This prospective, randomized, open-label, comparative study included 66 T2DM patients with HbA1c >7.5% even after receiving repeated education programs on Calorie-Restricted Dieting (CRD). They were randomly allocated to either the 130g/day Low-Carb Diet (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). [If I understand correctly, a 170-lb (77.2 kg) person would be recommended to eat 2160 calories/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.
At baseline, body mass index (BMI) and HbA1c were 26.5 and 8.3, and 26.7 kg/m2 and 8.0%, in the CRD and LCD, respectively. At the end of the study, HbA1c decreased by −0.65% in the LCD group, compared with 0.00% in the CRD group (p < 0.01). Also, the decrease in BMI in the LCD group [−0.58 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 type 2 diabetes. LCD is a potentially useful nutrition therapy for Japanese patients who cannot adhere to CRD.”
The calorie-restricted diet did nothing for these folks in terms of glycemic control.
Steve Parker, M.D.
PS: In case you’re wondering, the Low-Carb Mediterranean reduces digestible carbs to 20-100 grams/day.