title: High rates of fructose malabsorption are associated with reduced liver fat in obese African Americans.
abstract: OBJECTIVE
  African Americans commonly have lower liver fat accumulation than Hispanics, despite a similar propensity for obesity. Both ethnicities exhibit high consumption of fructose-containing beverages, which has been associated with high liver fat owing to the lipogenic properties of fructose. Therefore, differences in fructose absorption may be an important factor in regulating liver fat deposition. We hypothesized that fructose malabsorption in African Americans may reduce hepatic delivery of fructose, thus contributing to lower liver fat deposition compared to Hispanics.
  
  
  METHODS
  Thirty-seven obese young adults aged 21.4 ± 2.1 years (16 African American, 21 Hispanic) underwent a 3-hour hydrogen (H2) breath test to assess fructose malabsorption. Magnetic resonance imaging was used to determine visceral and subcutaneous adipose tissue volume and liver fat. Fructose malabsorption was expressed as an area under the curve for H2 production (H2 AUC).
  
  
  RESULTS
  Compared to Hispanics, African Americans had lower liver fat (5.4% ± 5.0% vs 8.9% ± 2.3%, p = 0.02) and a higher prevalence of fructose malabsorption (75.0% vs 42.9%; p = 0.05). Liver fat was negatively related to the extent of fructose malabsorption in African Americans (r = -0.53, p = 0.03), and this relationship was independent of the volumes of total fat and subcutaneous and visceral adipose tissue. There were no significant relationships between liver fat and fructose malabsorption in Hispanics.
  
  
  CONCLUSIONS
  African Americans have both a higher prevalence and a greater magnitude of fructose malabsorption than Hispanics. In African Americans, fructose malabsorption was negatively correlated with liver fat, which may be protective against fatty liver disease.
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California 90089, USA.
authors.forename: Ryan W
authors.initials: RW
authors.lastname: Walker
authors.forename: Kim-Anne
authors.initials: KA
authors.lastname: Lê
authors.forename: Jaime
authors.initials: J
authors.lastname: Davis
authors.forename: Tanya L
authors.initials: TL
authors.lastname: Alderete
authors.forename: Rebecca
authors.initials: R
authors.lastname: Cherry
authors.forename: Sylvie
authors.initials: S
authors.lastname: Lebel
authors.forename: Michael I
authors.initials: MI
authors.lastname: Goran
mesh_terms: D000293:Adolescent; D000328:Adult; D001741:Black or African American; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D001944:Breath Tests; D003430:Cross-Sectional Studies; D005215:Fasting; D005234:Fatty Liver / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D005632:Fructose / Q000008:administration & dosage* / Q000009:adverse effects*; D005633:Fructose Intolerance / Q000378:metabolism; D006630:Hispanic or Latino; D006801:Humans; D007333:Insulin Resistance; D050152:Intra-Abdominal Fat / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008286:Malabsorption Syndromes / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology; D008297:Male; D009765:Obesity / Q000150:complications / Q000453:epidemiology*; D050151:Subcutaneous Fat; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D005632:Fructose