title: The Mediterranean diet improves hepatic steatosis and insulin sensitivity in individuals with non-alcoholic fatty liver disease.
abstract: OBJECTIVE
  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 resonance (1)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 by (1)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.
authors.affiliation: Gastroenterology Department, St Vincent's Hospital, Melbourne, Australia. Marno.Ryan@svhm.org.au
authors.forename: Marno C
authors.initials: MC
authors.lastname: Ryan
authors.forename: Catherine
authors.initials: C
authors.lastname: Itsiopoulos
authors.forename: Tania
authors.initials: T
authors.lastname: Thodis
authors.forename: Glenn
authors.initials: G
authors.lastname: Ward
authors.forename: Nicholas
authors.initials: N
authors.lastname: Trost
authors.forename: Sophie
authors.initials: S
authors.lastname: Hofferberth
authors.forename: Kerin
authors.initials: K
authors.lastname: O'Dea
authors.forename: Paul V
authors.initials: PV
authors.lastname: Desmond
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Johnson
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Wilson
mesh_terms: D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D038441:Diet, Mediterranean; D005234:Fatty Liver / Q000178:diet therapy* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D007333:Insulin Resistance; D050356:Lipid Metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D056128:Obesity, Abdominal / Q000178:diet therapy / Q000378:metabolism / Q000473:pathology; D010865:Pilot Projects