title: Effects of solid versus liquid meal-replacement products of similar energy content on hunger, satiety, and appetite-regulating hormones in older adults.
abstract: OBJECTIVE
  To examine whether solid versus liquid meal-replacement products differentially affect appetite and appetite-regulating hormones in older adults.
  
  
  METHODS
  On two occasions, 9 subjects (age: 61+/-3 years; BMI: 25.6+/-1.3 kg/m (2)) consumed 25% of daily energy needs as solid or liquid meal-replacements of similar energy contents. Blood and appetite ratings were collected over 4 hours.
  
  
  RESULTS
  The post-prandial hunger composite (area under the curve) was lower following the solid versus liquid meal-replacement (p<0.005) and remained below baseline over 4 hours (p<0.05). Similar responses were observed with the desire to eat. The insulin and ghrelin composites were lower following the solid trial compared to the liquid [insulin: 5825 (range: 4676-11639) VS. 7170 (4472-14169) uIU/l x 240 min, p<0.01; ghrelin: -92798 (range: -269130-47528) VS. -56152 (range: -390855-30840) pg/ml x 240 min, p<0.05]. Ghrelin also remained below baseline over 4 hours (p<0.05). No differences in cholecystokinin and leptin were observed between products.
  
  
  CONCLUSIONS
  The consumption of comparable meal-replacement products in solid versus liquid versions with similar energy contents led to differential appetitive responses and should not be viewed as dietary equivalents in older adults.
authors.affiliation: Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Tieken
authors.forename: H J
authors.initials: HJ
authors.lastname: Leidy
authors.forename: A J
authors.initials: AJ
authors.lastname: Stull
authors.forename: R D
authors.initials: RD
authors.lastname: Mattes
authors.forename: R A
authors.initials: RA
authors.lastname: Schuster
authors.forename: W W
authors.initials: WW
authors.lastname: Campbell
mesh_terms: D001066:Appetite / Q000502:physiology*; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002766:Cholecystokinin / Q000097:blood; D002149:Energy Intake / Q000502:physiology*; D005260:Female; D005526:Food, Formulated; D054439:Ghrelin; D006801:Humans; D006815:Hunger / Q000502:physiology*; D007328:Insulin / Q000097:blood / Q000502:physiology; D020738:Leptin / Q000097:blood; D008297:Male; D008875:Middle Aged; D036361:Peptide Hormones / Q000097:blood / Q000502:physiology; D012528:Satiety Response / Q000502:physiology*
chemical_list: D001786:Blood Glucose; D054439:Ghrelin; D007328:Insulin; D020738:Leptin; D036361:Peptide Hormones; D002766:Cholecystokinin