The Mediterranean diet improves hepatic steatosis and insulin sensitivity in individuals with non-alcoholic fatty liver disease

• Published in: Journal of hepatology 2013-07, Vol.59 (1), p.138-143
• Main Authors: Ryan, Marno C, Itsiopoulos, Catherine, Thodis, Tania, Ward, Glenn, Trost, Nicholas, Hofferberth, Sophie, O’Dea, Kerin, Desmond, Paul V, Johnson, Nathan A, Wilson, Andrew M
• Format: Article
• Language: English
• Subjects: Adult; Aged; Cardiovascular risk; Cross-Over Studies; Diet; Diet, Mediterranean; Fatty acids; Fatty Liver - diet therapy; Fatty Liver - metabolism; Fatty Liver - pathology; Female; Gastroenterology and Hepatology; Glucose Clamp Technique; Humans; Insulin Resistance; Lipid Metabolism; Liver fat; Magnetic Resonance Imaging; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Obesity, Abdominal - diet therapy; Obesity, Abdominal - metabolism; Obesity, Abdominal - pathology; Pilot Projects
• ISSN: 0168-8278; 1600-0641
• DOI: 10.1016/j.jhep.2013.02.012

Background & Aims Non-alcoholic fatty liver disease (NAFLD) affects up to 30% of the population and signifies increased risk of liver fibrosis and cirrhosis, type 2 diabetes, and cardiovascular disease. Therapies are limited. Weight loss is of benefit but is difficult to maintain. We aimed at examining the effect of the Mediterranean diet (MD), a diet high in monounsaturated fatty acids, on steatosis and insulin sensitivity, using gold standard techniques. Methods Twelve non-diabetic subjects (6 Females/6 Males) with biopsy-proven NAFLD were recruited for a randomised, cross-over 6-week dietary intervention study. All subjects undertook both the MD and a control diet, a low fat-high carbohydrate diet (LF/HCD), in random order with a 6-week wash-out period in- between. Insulin sensitivity was determined with a 3-h hyperinsulinemic–euglycemic clamp study and hepatic steatosis was assessed with localized magnetic resonance1 H spectroscopy (1 H-MRS). Results At baseline, subjects were abdominally obese with elevated fasting concentrations of glucose, insulin, triglycerides, ALT, and GGT. Insulin sensitivity at baseline was low (M = 2.7 ± 1.0 mg/kg/min−1 ). Mean weight loss was not different between the two diets ( p = 0.22). There was a significant relative reduction in hepatic steatosis after the MD compared with the LF/HCD: 39 ± 4% versus 7 ± 3%, as measured by1 H-MRS ( p = 0.012). Insulin sensitivity improved with the MD, whereas after the LF/HCD there was no change ( p = 0.03 between diets). Conclusions Even without weight loss, MD reduces liver steatosis and improves insulin sensitivity in an insulin-resistant population with NAFLD, compared to current dietary advice. This diet should be further investigated in subjects with NAFLD.