title: Effects of acute and longer-term dietary restriction on upper gut motility, hormone, appetite, and energy-intake responses to duodenal lipid in lean and obese men.
abstract: BACKGROUND
  A 4-d 70% energy restriction enhances gastrointestinal sensitivity to nutrients associated with enhanced energy-intake suppression by lipid. To our knowledge, it is unknown whether these changes occur with 30% energy restriction and are sustained in the longer term.
  
  
  OBJECTIVE
  We hypothesized that 1) a 4-d 30% energy restriction would enhance effects of intraduodenal lipid on gastrointestinal motility, gut hormones, appetite, and energy intake in lean and obese men and 2) a 12-wk energy restriction associated with weight loss would diminish effects of acute energy restriction on responses to lipid in in obese men.
  
  
  METHODS
  Twelve obese males were studied before (day 0) and after 4 d (day 5), 4 wk (week 4), and 12 wk (week 12), and 12 lean males were studied before and after 4 d of consumption of a 30% energy-restricted diet. On each study day, antropyloroduodenal pressures, gut hormones, and appetite during a 120-min (2.86-kcal/min) intraduodenal lipid infusion and energy intake at a buffet lunch were measured.
  
  
  RESULTS
  On day 5, fasting cholecystokinin was less, and ghrelin was higher, in lean (P < 0.05) but not obese men, and lipid-stimulated cholecystokinin and peptide YY and the desire to eat were greater in both groups (P < 0.05), with no differences in energy intakes compared with on day 0. In obese men, a 12-wk energy restriction led to weight loss (9.7 ± 0.7 kg). Lipid-induced basal pyloric pressures (BPPs), peptide YY, and the desire to eat were greater (P < 0.05), whereas the amount eaten was less (P < 0.05), at weeks 4 and 12 compared with day 0.
  
  
  CONCLUSIONS
  A 4-d 30% energy restriction modestly affects responses to intraduodenal lipid in health and obesity but not energy intake, whereas a 12-wk energy restriction, associated with weight-loss, enhances lipid-induced BPP and peptide YY and reduces food intake, suggesting that energy restriction increases gastrointestinal sensitivity to lipid. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as 12609000943246.
authors.affiliation: University of Adelaide Discipline of Medicine, Royal Adelaide Hospital, Adelaide, Australia (RVS, TJL, SS, MH, and CF-B); the National Health and Medical Research Council of Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide, Australia (RVS, TJL, MN, SS, PMC, MH, and CF-B); the Commomwealth Science and Industry Research Organisation Animal, Food and Health Science, Adelaide, Australia (PT and MN); and the University of South Australia, Adelaide, Australia (PMC).
authors.forename: Radhika V
authors.initials: RV
authors.lastname: Seimon
authors.forename: Pennie
authors.initials: P
authors.lastname: Taylor
authors.forename: Tanya J
authors.initials: TJ
authors.lastname: Little
authors.forename: Manny
authors.initials: M
authors.lastname: Noakes
authors.forename: Scott
authors.initials: S
authors.lastname: Standfield
authors.forename: Peter M
authors.initials: PM
authors.lastname: Clifton
authors.forename: Michael
authors.initials: M
authors.lastname: Horowitz
authors.forename: Christine
authors.initials: C
authors.lastname: Feinle-Bisset
mesh_terms: D000328:Adult; D000886:Anthropometry; D001066:Appetite / Q000502:physiology*; D002766:Cholecystokinin / Q000378:metabolism; D004032:Diet; D004386:Duodenum / Q000378:metabolism*; D002149:Energy Intake / Q000502:physiology*; D005215:Fasting; D005247:Feeding Behavior; D005769:Gastrointestinal Motility / Q000502:physiology*; D054439:Ghrelin / Q000378:metabolism; D006801:Humans; D008019:Life Style; D050356:Lipid Metabolism / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009520:New Zealand; D009765:Obesity / Q000378:metabolism*; D019894:Peptide YY / Q000378:metabolism; D011708:Pylorus / Q000378:metabolism; D013851:Thinness / Q000378:metabolism*; D055815:Young Adult
chemical_list: D054439:Ghrelin; D019894:Peptide YY; D002766:Cholecystokinin