The effect of mediterranean diet and low-fat diet on hepatic fat, inflammation and oxidative stress in obese adolescents with nonalcoholic fatty liver disease

This study was conducted to evaluate the effect of Mediterranean and low-fat diet on hepatic fat, inflammation and oxidative stress in obese adolescents with nonalcoholic fatty liver disease (NAFLD). The study, which was designed as a single blind randomized control, was completed with 44 obese adolescents diagnosed with NAFLD between the ages of 11-18. Adolescents were randomized to either a Mediterranean diet (n = 22) or a low-fat diet (control diet) (n = 22) for 12 weeks. At the beginning of the study and at the 12th week, adolescents' blood samples, physical activity and food consumption records were taken, anthropometric measurements and body composition analyzes were made, and antioxidant food consumption frequency and Mediterranean diet quality index questionnaire were applied to adolescents. In the controls performed at the 2th, 4th, 6th, 8th, and 10th weeks, the physical activity and food consumption records of the adolescents were repeated and anthropometric measurements and body composition analyzes were made again. At the end of the study, body weight, body mass index, waist circumference, hip circumference, neck circumference, waist / hip ratio, body fat percentage and mass values significantly decreased in both diet groups (p <0.05). At the end of the study in both diet groups, the degree of fatty liver and serum transaminase levels decreased significantly (p <0.05). It was determined that the amount of decrease in aspartate aminotransferase (AST) levels in the Mediterranean diet group was greater than that in the low-fat diet group (p <0.05). Serum insulin levels and insulin resistance decreased significantly at the end of the study in both diet groups (p <0.05). At the end of the study in the Mediterranean diet group, serum total antioxidant capacity, paraoxanase-1 and glutathione peroxidase levels increased (p <0.05); It was observed that it did not change in the low-fat diet group (p> 0.05). It was found that the amount of increase in glutathione and glutathione peroxidase levels in the Mediterranean diet group compared to the baseline was greater than that in the low-fat diet group (p <0.05). Malondialdehyde levels significantly decreased at the end of the study in both diet groups (p <0.05). It was determined that C-Reactive Protein (CRP) levels of individuals in the Mediterranean diet group decreased (p <0.05) at the end of the study, whereas there was no significant change in the low-fat diet group (p> 0.05). At the end of the study, serum leptin and adiponectin levels were significantly decreased in both diet groups (p <0.05). In conclusion, it has been determined that the Mediterranean diet reduces hepatic steatosis and insulin resistance, improves high transaminase levels, and has positive effects on oxidative stress and inflammation in obese adolescents with NAFLD.