title: Additive effects of moderate drinking and obesity on serum gamma-glutamyl transferase activity.
abstract: BACKGROUND
  Gamma-glutamyl transferase (GGT) is a widely used index of liver induction and a marker of alcohol overconsumption. Obesity has also been suggested to elevate serum GGT activities.
  
  
  OBJECTIVE
  The aim was to examine the links between moderate ethanol consumption, obesity, and GGT activities.
  
  
  METHODS
  GGT values were recorded from 2490 persons (1184 men and 1306 women) who reported either no alcohol use (abstainers) or 1-40 g ethanol consumption per day (moderate drinkers). The study population was additionally classified according to body mass index (BMI; in kg/m2) as follows: < 19 (underweight), > or = 19 and < 25 (normal weight), > or = 25 and < 30 (overweight), and 30 (obese).
  
  
  RESULTS
  Significant main effects of sex (P < 0.0001), drinking habits (P < 0.01), and BMI (P < 0.001) on serum GGT activities were observed. The values were higher in the men than in the women and higher in those with higher BMIs. The highest activities were found to occur in persons with moderate drinking combined with overweight or obesity. A significant positive correlation between GGT and BMI (P < 0.0001) was observed, which was stronger for the men (r = 0.24) than for the women (r = 0.15, P < 0.05 for the difference between correlations).
  
  
  CONCLUSIONS
  The data indicate that serum GGT activities may respond to moderate drinking and overweight in an additive manner; this should be considered in the clinical use of GGT measurements and when defining normal GGT values in health care.
authors.affiliation: Department of Laboratory Medicine Research Unit, Seinäjoki Central Hospital, Seinäjoki, Finland.
authors.forename: Katri
authors.initials: K
authors.lastname: Puukka
authors.forename: Johanna
authors.initials: J
authors.lastname: Hietala
authors.forename: Heidi
authors.initials: H
authors.lastname: Koivisto
authors.forename: Petra
authors.initials: P
authors.lastname: Anttila
authors.forename: Risto
authors.initials: R
authors.lastname: Bloigu
authors.forename: Onni
authors.initials: O
authors.lastname: Niemelä
mesh_terms: D000428:Alcohol Drinking / Q000453:epidemiology; D015992:Body Mass Index; D000431:Ethanol / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood*; D011159:Population Surveillance / Q000379:methods*; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D000431:Ethanol; D005723:gamma-Glutamyltransferase