How Much Weight Loss is Effective on Nonalcoholic Fatty Liver Disease?

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide with no specific treatment. Weight loss is the most effective therapeutic strategy in its management; however, there is no consensus on its specifics. Thus, this study was conducted to evaluate the effects of weight loss on liver enzymes, markers of inflammation, oxidative stress and CK18-M30 (cytokeratin 18) as a biomarker of hepatocellular apoptosis. OBJECTIVES: To study the effect of weight reduction diet as an exclusive treatment for NAFLD. PATIENTS AND METHODS: Forty four patients with NAFLD received a diet including a 500 to 1000 kcal per day intake reduction as30% fat, 15% protein, and 55% carbohydrate for six months. Anthropometric parameters, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), lipid profile, malondialdehyde (MDA), TNF-α, IL-6, CK18-M30 were measured at baseline and at the end of the study. At the end of follow up, patients were classified as adherent or nonadherent to treatment according to a weight loss of ≥ 5%, or < 5% of initial body weight, respectively. RESULTS: Twenty five patients were classified as adherent group and nineteen as nonadherent group (9.7% vs. 1.9% total body weight loss after 6 months, respectively). After 6 months, changes in adherent and nonadherent groups were as follows: reduction in body weight from 93.7 ± 15.8 kg to 84.2 ± 13.4 kg vs. 94 ± 16.6 kg to 92.2 ± 16.2 kg (P < 0.05), BMI from 32.7 ± 3.9 to 29.5 ± 3.2 vs.31.8 ± 5.4 to 31.1 ± 5.3 (P < 0.001), and waist circumference from 105.1 ± 12.6 cm to 97.4 ± 9.8 cm vs.106.8 ± 14.2 cm to 103.7 ± 14 cm (P < 0.001), respectively. Diastolic blood pressure was significantly decreased in adherent group (from 80.2 ± 5.1 mmHg to 76.9 ± 5 mmHg; P < 0.001). Also, total cholesterol, LDL, triglyceride, ALT, AST, GGT and CK18-M30 levels were significantly decreased in the adherent group compared to nonadherent group (P < 0.05). CONCLUSIONS: This intervention offers a practical approach for treatment of patients with NAFLD with diet therapy.