title: Timing of fat and liquid sugar intake alters substrate oxidation and food efficiency in male Wistar rats.
abstract: In addition to the amount of ingested calories, both timing of food intake and meal composition are determinants of body weight gain. However, at present, it is unknown if the inappropriate timing of diet components is responsible for body weight gain. In the present study, we therefore studied a time-dependent effect of the diet composition on energy homeostasis. Male Wistar rats were subjected to chow ad libitum (chow group) or a choice diet with saturated fat, a 30% sugar solution, chow and tap water. The choice diet was provided either with all components ad libitum (AL), with ad libitum access to chow, tap water and a 30% sugar solution, but with access to saturated fat only during the light period (LF), or with ad libitum access to chow, tap water and saturated fat, but access to a 30% sugar solution only during the light period (LS). Caloric intake and body weight gain were monitored during 31 days. Energy expenditure was measured in the third week in calorimetric cages. All rats on a choice diet showed hyperphagia and gained more body weight compared to the chow group. Within the choice diet groups, rats on the LS diet were most food efficient (i.e. gained most body weight per ingested calorie) and showed a lower respiratory exchange ratio (RER) with an anti-phasic pattern, whereas no differences in locomotor activity or heat production were found. Collectively these data indicate that the timing of the diet composition affects food efficiency, most likely due to a shifted oxidation pattern, which can predispose for obesity. Further studies are underway to assess putative mechanisms involved in this dysregulation.
authors.affiliation: Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam , Amsterdam , The Netherlands and.
authors.forename: Johanneke E
authors.initials: JE
authors.lastname: Oosterman
authors.forename: Ewout
authors.initials: E
authors.lastname: Foppen
authors.forename: Rianne
authors.initials: R
authors.lastname: van der Spek
authors.forename: Eric
authors.initials: E
authors.lastname: Fliers
authors.forename: Andries
authors.initials: A
authors.lastname: Kalsbeek
authors.forename: Susanne E
authors.initials: SE
authors.lastname: la Fleur
mesh_terms: D000818:Animals; D001823:Body Composition; D001835:Body Weight; D002151:Calorimetry; D002940:Circadian Rhythm; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage*; D019422:Dietary Sucrose / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004435:Eating / Q000502:physiology*; D002149:Energy Intake / Q000502:physiology; D005247:Feeding Behavior; D006706:Homeostasis; D020738:Leptin / Q000097:blood; D008027:Light; D008297:Male; D009765:Obesity / Q000503:physiopathology; D010100:Oxygen / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D015430:Weight Gain
chemical_list: D004041:Dietary Fats; D019422:Dietary Sucrose; D020738:Leptin; D010100:Oxygen
keywords: Chronobiology; daily eating pattern; energy homeostasis; food efficiency; high-fat high-sugar diet; obesity