Objective: Nutrition therapy is indispensable in the management of obesity. Low-carb diet is one of the recommended diets. On the other hand, there is little evidence on Low-carb diet in Japan. Besides, we don’t know the optimum amount of carbohydrate. So, we tried to ellucidate the efficacy and safeness of Low-carb diet, and to compare two amounts of Low-carb diet: 50g (LC50g) or 120g carb/day (LC120g).

Research Design and Methods: 42 Overweight or obese Japanese adults with one or more metabolic disorders (such as diabetes, hyperlipidemia, hypertension) were randomly assigned to a 3-month Low-Carb diet intervension (50g or 120g carb/day). All food was provided, and patients were assigned to report what they ate every day to the registered dietitian via mail, so that we could check compliance. Total calorie was calculated based on the ideal body weight and physical activity index. Every month, body weight, body composition (measured by multi-frequency BIA) were checked. Blood pressure, HbA1c, FPG, serum ketone body, kidney and liver function and lipid profile, serum C-peptide, urinary albumin, PWV/ABI were checked. We used T test for statistic analysis.

Results: No one dropped out. Median age and BMI were 43 and 28.5. Change in BW was -8.5kg in LC50g, -7.2kg in LC120g, there was no significant difference. AST, ALT, γGTP, LDH, Cre decreased after intervention in both groups. LDH, Cre significantly decreased in LC50g. Acetoacetic acid and EPA significantly increased in LC50g. Baseline analysis showed, BW at age 20, early rising, dinner time and exercise habits were related to susceptibility to losing weight. A questionnaires survey revealed patients felt more stressful in LC50g.

Conclusion: In this study, both amount of carb restriction was effective and safe, and there was no significant difference in losing weight, diabetes, lipid and hypertension control. LC120g was easy to carry out. Finally, this study is the one and only because it achieved high compliance by food offering and on time follow-up.


T. Kikuchi: None.

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