title: Effect of long-term changes in diet and exercise on plasma leptin concentrations.
abstract: BACKGROUND
  Although it is known that plasma leptin concentrations correlate with the amount of adipose tissue in the body, little information is available on the long-term effects on leptin concentrations of changes in diet and exercise.
  
  
  OBJECTIVE
  We wanted to examine whether changes in dietary energy sources and exercise-mediated energy expenditure, alone or in combination, affect plasma leptin concentrations.
  
  
  METHODS
  In a randomized, 2 x 2 factorial trial, 186 men with metabolic syndrome were divided into 4 groups: diet, exercise, a combination of diet and exercise, and control. Data on dietary intake, physical fitness, and demographics were collected and plasma leptin concentrations were measured before and after a 1-y intervention period.
  
  
  RESULTS
  Plasma leptin concentrations, body mass index, and fat mass decreased in association with long-term reductions in food intake as well as increased physical activity. By adjusting for either body mass index or fat mass, we observed a highly significant reduction in plasma leptin concentration after both the diet and the exercise interventions. There was no interaction between the interventions, suggesting a direct and additive effect of changes in diet and physical activity on plasma leptin concentrations.
  
  
  CONCLUSIONS
  Long-term changes in lifestyle consisting of decreased intake of dietary fat and increased physical activity reduced plasma leptin concentrations in humans beyond the reduction expected as a result of changes in fat mass.
authors.affiliation: Institute for Nutrition Research, University of Oslo, Norway. j.e.reseland@basalmed.uio.no
authors.forename: J E
authors.initials: JE
authors.lastname: Reseland
authors.forename: S A
authors.initials: SA
authors.lastname: Anderssen
authors.forename: K
authors.initials: K
authors.lastname: Solvoll
authors.forename: I
authors.initials: I
authors.lastname: Hjermann
authors.forename: P
authors.initials: P
authors.lastname: Urdal
authors.forename: I
authors.initials: I
authors.lastname: Holme
authors.forename: C A
authors.initials: CA
authors.lastname: Drevon
mesh_terms: D000273:Adipose Tissue; D000328:Adult; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage; D015444:Exercise; D015438:Health Behavior; D006801:Humans; D007333:Insulin Resistance; D020738:Leptin / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012907:Smoking; D015431:Weight Loss
chemical_list: D004041:Dietary Fats; D020738:Leptin