title: Controlling access time to a high-fat diet during the inactive period protects against obesity in mice.
abstract: Free feeding (FF) with a high fat diet (HFD) causes excessive body weight gain, whereas restricted feeding (RF) with a HFD attenuates body weight gain. The effects of timing of feeding with a HFD (day vs. night) and feeding duration on energy homeostasis have not yet been investigated. In this study, we fed mice a HFD or a normal diet (ND) twice a day, during their active and inactive periods, on a schedule. The amount of food was regulated by feeding duration (2, 4 or 8 h). First, we investigated the effects of 4-h RF during active-inactive periods (ND-ND, HFD-HFD, ND-HFD or HFD-ND). Among all the 4-h RF groups, mice consumed almost the same amount of calories as those in the FF[ND] group, even those fed a HFD. Body weight and visceral fat in these three groups were lower than that in the FF[HFD] group. Second, we investigated the effects of RF duration. Body weight and visceral fat were higher in the 8-h groups than in the 4-h groups. Body weight and visceral fat were higher in the 2-h groups than in the 4-h groups even though the 2-h groups had less food. Third, we investigated the effects of eating a HFD during the inactive period, when RF duration was extended (2, 6 or 12 h). Mice were fed with a HFD during the inactive period for 2 h and fed with a ND during the active period for 2, 6 or 12 h. Body weight and visceral fat in these mice were comparable to those in the FF[ND] mice. The results of our first set of experiments suggest that 4-h RF was an adequate feeding duration to control the effect of a HFD on obesity. The results of our second set of experiments suggest 2-h RF (such as speed-eating) and 8-h RF, representative of eating disorders, are unhealthy feeding patterns related to obesity. The results of our third set of experiments suggest that eating a HFD for a short period during the night does not affect body weight and visceral fat. Taken together, these results indicate that consideration to feeding with a HFD during the inactive period and restricting eating habits relieve the risks of body weight gain and visceral fat accumulation.
authors.affiliation: Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University , Tokyo , Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Haraguchi
authors.forename: Natsumi
authors.initials: N
authors.lastname: Aoki
authors.forename: Teiji
authors.initials: T
authors.lastname: Ohtsu
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ikeda
authors.forename: Yu
authors.initials: Y
authors.lastname: Tahara
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Shibata
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002940:Circadian Rhythm; D059305:Diet, High-Fat; D004041:Dietary Fats; D002149:Energy Intake; D005247:Feeding Behavior; D007328:Insulin / Q000097:blood; D050152:Intra-Abdominal Fat / Q000473:pathology; D020738:Leptin / Q000097:blood; D008099:Liver / Q000503:physiopathology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009765:Obesity / Q000503:physiopathology*; D013997:Time Factors; D015430:Weight Gain
chemical_list: D001786:Blood Glucose; D004041:Dietary Fats; D007328:Insulin; D020738:Leptin
keywords: Circadian rhythm; high fat diet; liver; night eating; period; phase