Background: Nutrition therapies for type 2 diabetes (T2DM) and nonalcoholic fatty liver disease (NAFLD) are recommended for calorie-restricted diet (CRD) in Japan. Recently, the efficacy of low-carbohydrate diet (LCD) has been reported in these diseases. This study aimed to determine the effects of LCD on NAFLD in Japanese patients with T2DM compared with CRD.

Methods: We assigned 28 patients of NAFLD with T2DM in this 3-month prospective open-label randomized comparative trial. They were randomly allocated to either LCD (70-130 g/day of carbohydrate) group (n =14) or CRD (calories of 25 kcal/kg of ideal body weight per day) group (n =14). Abdominal computed tomography (CT) scan evaluated liver fat deposition by the liver-to-spleen attenuation ratio (L/S ratio) and visceral fat accumulation as the visceral fat area (VFA).

Results: The average age of patients at the start was 50 years old, BMI was 31 kg/m2, L/S ratio was 0.7, VFA was 163 cm2. The total intake energy of LCD after 3 months was 1,389 kcal (δ-386 kcal from the start, carbohydrate was 42% of the total energy), CRD was 1,513 kcal (δ-633 kcal, carbohydrate was 54%). Both diets achieved significantly improvement of L/S ratio, VFA, liver transaminase, body weight and HbA1c from baseline within groups after 3 months (P < 0.05). Between the two diets, L/S ratio, liver transaminase, body weight and HbA1c showed a large tendency to improve in LCD, but no significant difference was noted. Significant improvement was observed in VFA of LCD. In the QoL score, "anxiety and dissatisfaction with treatment" was significantly improved in LCD.

Conclusions: Our findings suggest that LCD may be as effective as CRD in improving fatty liver in Japanese patients of NAFLD with T2DM, and that LCD may be less burdensome on patients than CRD.


E. Nishimori: None. S. Ogata: None. M. Naka: None.

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