title: Effect of hydration status and fluid availability on ad-libitum energy intake of a semi-solid breakfast.
abstract: This study investigated the effects of hydration status and fluid availability on appetite and energy intake. Sixteen males completed four 24 h trials, visiting the laboratory overnight fasted on two consecutive days. Standardised foods were provided during the 24 h and on day two an ad-libitum semi-solid porridge breakfast was provided. Water intake during the 24 h (0 or 40 mL⋅kg(-1)) and fluid provision during the ad-libitum breakfast were manipulated so subjects were euhydrated with (EU-F) and without fluid (EU-NF) available at breakfast; and hypohydrated with (HYPO-F) and without fluid (HYPO-NF) available at breakfast. Blood samples (0 and 24 h), urine samples (0-24 h) and subjective responses (0, 24 and 24.5 h) were collected. HYPO trials decreased body mass by ~1.8%. Serum and urine osmolality increased and plasma volume decreased during HYPO trials (P <0.001). Total urine output was greater during EU than HYPO trials (P <0.001). Ad-libitum energy intake was not different between trials: 2658 (938) kJ (EU-F), 2353 (643) kJ (EU-NF), 2295 (529) kJ (HYPO-F), 2414 (954) kJ (HYPO-NF), (P = 0.131). Fluid intake was ~200 mL greater during HYPO-F than EU-F (P <0.01). There was an interaction effect for thirst (P < 0.001), but not hunger or fullness. These results demonstrate that mild hypohydration produced by inadequate fluid intake and fluid availability during eating does not influence ad-libitum energy intake of a semi-solid breakfast, at least in healthy young males.
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Corney
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK.
authors.forename: Anja
authors.initials: A
authors.lastname: Horina
authors.affiliation: School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK.
authors.forename: Caroline
authors.initials: C
authors.lastname: Sunderland
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK. Electronic address: L.james@lboro.ac.uk.
authors.forename: Lewis J
authors.initials: LJ
authors.lastname: James
mesh_terms: D000328:Adult; D001066:Appetite; D062408:Breakfast; D003681:Dehydration / Q000503:physiopathology; D004326:Drinking / Q000502:physiology; D004435:Eating; D002149:Energy Intake; D005215:Fasting; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D012527:Satiation; D012528:Satiety Response; D013894:Thirst; D014554:Urination; D014882:Water-Electrolyte Balance; D055815:Young Adult
keywords: Appetite; Dehydration; Fluid restriction; Hunger; Hypohydration; Water