title: Time-of-day-dependent dietary fat consumption influences multiple cardiometabolic syndrome parameters in mice.
abstract: BACKGROUND
  Excess caloric intake is strongly associated with the development of increased adiposity, glucose intolerance, insulin resistance, dyslipidemia, and hyperleptinemia (that is the cardiometabolic syndrome). Research efforts have focused attention primarily on the quality (that is nutritional content) and/or quantity of ingested calories as potential causes for diet-induced pathology. Despite growing acceptance that biological rhythms profoundly influence energy homeostasis, little is known regarding how the timing of nutrient ingestion influences development of common metabolic diseases.
  
  
  OBJECTIVE
  To test the hypothesis that the time of day at which dietary fat is consumed significantly influences multiple cardiometabolic syndrome parameters.
  
  
  RESULTS
  We report that mice fed either low- or high-fat diets in a contiguous manner during the 12  h awake/active period adjust both food intake and energy expenditure appropriately, such that metabolic parameters are maintained within a normal physiologic range. In contrast, fluctuation in dietary composition during the active period (as occurs in human beings) markedly influences whole body metabolic homeostasis. Mice fed a high-fat meal at the beginning of the active period retain metabolic flexibility in response to dietary challenges later in the active period (as revealed by indirect calorimetry). Conversely, consumption of high-fat meal at the end of the active phase leads to increased weight gain, adiposity, glucose intolerance, hyperinsulinemia, hypertriglyceridemia, and hyperleptinemia (that is cardiometabolic syndrome) in mice. The latter perturbations in energy/metabolic homeostasis are independent of daily total or fat-derived calories.
  
  
  CONCLUSIONS
  The time of day at which carbohydrate versus fat is consumed markedly influences multiple cardiometabolic syndrome parameters.
authors.affiliation: Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Bray
authors.forename: J-Y
authors.initials: JY
authors.lastname: Tsai
authors.forename: C
authors.initials: C
authors.lastname: Villegas-Montoya
authors.forename: B B
authors.initials: BB
authors.lastname: Boland
authors.forename: Z
authors.initials: Z
authors.lastname: Blasier
authors.forename: O
authors.initials: O
authors.lastname: Egbejimi
authors.forename: M
authors.initials: M
authors.lastname: Kueht
authors.forename: M E
authors.initials: ME
authors.lastname: Young
mesh_terms: D000818:Animals; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004041:Dietary Fats / Q000008:administration & dosage*; D050171:Dyslipidemias / Q000503:physiopathology*; D002149:Energy Intake / Q000502:physiology; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D051379:Mice; D009765:Obesity / Q000503:physiopathology*; D010507:Periodicity; D013997:Time Factors; D015430:Weight Gain / Q000502:physiology*
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats