title: Decreases in fasting leptin and insulin concentrations after acute energy restriction and subsequent compensation in food intake.
abstract: BACKGROUND
  The decrease in leptin after energy restriction is a starvation signal to the brain. Several studies have found an association between this decrease and subjective appetite; however, no solid data are available on the acute decrease in fasting leptin concentration and subsequent caloric compensation.
  
  
  OBJECTIVE
  The objective was to assess the effect of acute decreases in fasting leptin concentrations, induced by energy restriction, on subsequent energy intake compensation. We hypothesized that men with a large decrease in fasting leptin concentrations would have larger ad libitum energy intakes than would men with a small decrease in leptin.
  
  
  METHODS
  Thirty-four male unrestrained eaters [age: 23 +/- 3 y; body mass index (in kg/m(2)): 22.3 +/- 1.6] participated in a semicontrolled intervention study. Fasting serum leptin and insulin concentrations were measured before and 2 d after 62% energy restriction. Energy intake was measured on the 2 following days on which food was provided ad libitum.
  
  
  RESULTS
  During energy restriction, fasting leptin and insulin concentrations decreased by 27.2% (95% CI: -34.4%, -19.9%) and 30.7% (95% CI: -41.0%, -20.4%), respectively. Subjects consumed 143 +/- 27% of their estimated energy requirements (18.3 +/- 2.9 MJ) on the first day and 124 +/- 20% (16.0 +/- 2.6 MJ) on the second day of ad libitum intake. No significant correlations were observed between decreases in fasting leptin or insulin concentrations and subsequent ad libitum energy intake; however, decreases in insulin were correlated with an increase in carbohydrate intake (r=-0.49, P < 0.01).
  
  
  CONCLUSIONS
  Although fasting leptin concentrations decreased significantly during energy restriction and subjects showed compensatory behavior during subsequent ad libitum food intake, no association was observed between the decrease in fasting leptin concentrations and caloric compensation.
authors.affiliation: Division of Human Nutrition, Wageningen University, Wageningen, Netherlands. monica.mars@wur.nl
authors.forename: Monica
authors.initials: M
authors.lastname: Mars
authors.forename: Cees
authors.initials: C
authors.lastname: de Graaf
authors.forename: Lisette C P G M
authors.initials: LC
authors.lastname: de Groot
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Kok
mesh_terms: D000328:Adult; D001066:Appetite / Q000502:physiology; D016001:Confidence Intervals; D004040:Dietary Carbohydrates / Q000008:administration & dosage* / Q000378:metabolism; D004435:Eating / Q000502:physiology*; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D005215:Fasting / Q000097:blood* / Q000502:physiology; D006801:Humans; D007328:Insulin / Q000097:blood*; D020738:Leptin / Q000097:blood*; D008297:Male; D009751:Nutritional Requirements; D016017:Odds Ratio; D013217:Starvation / Q000097:blood / Q000503:physiopathology
chemical_list: D004040:Dietary Carbohydrates; D007328:Insulin; D020738:Leptin