title: One day of overfeeding impairs nocturnal glucose but not fatty acid homeostasis in overweight men.
abstract: OBJECTIVE
  Overfeeding is associated with insulin resistance. Studies on animals suggest this is likely due to disruption of fatty acid metabolism and increased plasma free fatty acid (FFA) availability during the night. We tested the hypothesis that overfeeding induces insulin resistance and increases nocturnal but not daytime plasma FFA availability in human subjects.
  
  
  METHODS
  We measured plasma glucose, insulin, and FFA concentrations hourly for 24 h during a day of isocaloric feeding and a day of hypercaloric feeding (30% calorie excess) in 8 overweight and obese, nondiabetic men (age: 38±3 years; body mass index: 34±2 kg/m²).
  
  
  RESULTS
  Overfeeding had no effect on daytime plasma glucose, insulin, and FFA concentrations compared to isocaloric feeding, but increased nocturnal glucose (P = 0.007) and insulin (P = 0.003) concentrations and decreased nocturnal FFA concentration (P = 0.006). The homeostasis model assessment of insulin resistance score was ∼30% greater the morning after hypercaloric than isocaloric feeding (P = 0.040).
  
  
  CONCLUSIONS
  One day of overfeeding has no effect on daytime plasma glucose and FFA concentrations but increases nocturnal plasma glucose and insulin concentrations, whereas nocturnal plasma FFA availability is reduced. The acute overfeeding-induced development of insulin resistant glucose metabolism therefore does not appear to be directly mediated by plasma FFA availability.
authors.affiliation: Division of Geriatrics and Nutritional Science, Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA.
authors.forename: Faidon
authors.initials: F
authors.lastname: Magkos
authors.forename: Gordon I
authors.initials: GI
authors.lastname: Smith
authors.forename: Dominic N
authors.initials: DN
authors.lastname: Reeds
authors.forename: Adewole
authors.initials: A
authors.lastname: Okunade
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Patterson
authors.forename: Bettina
authors.initials: B
authors.lastname: Mittendorfer
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D052636:Allostasis; D001786:Blood Glucose; D015992:Body Mass Index; D002940:Circadian Rhythm; D005230:Fatty Acids, Nonesterified / Q000097:blood* / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D006943:Hyperglycemia / Q000209:etiology*; D006946:Hyperinsulinism / Q000209:etiology*; D006963:Hyperphagia / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008099:Liver / Q000378:metabolism; D008297:Male; D009132:Muscles / Q000378:metabolism; D009765:Obesity / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D050177:Overweight / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D062410:Snacks
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin
keywords: diurnal; hypercaloric; insulin resistance; overnight