{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T23:48:20Z","timestamp":1787788100000,"version":"build-2784847793"},"reference-count":33,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,23]],"date-time":"2024-09-23T00:00:00Z","timestamp":1727049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Purpose: To investigate the effects of thirst on later hydration status, total water intake (TWI-MA), and its potential sex differences. Methods: Twelve men (mean \u00b1 standard deviation; age: 21 \u00b1 2 years; mass: 81.0 \u00b1 15.9 kg) and twelve women (age: 22 \u00b1 3 years; mass: 68.8 \u00b1 15.2 kg) visited the laboratory in the morning (first thing in the morning) and afternoon (2:00\u20134:00 p.m.) for three consecutive days under a free-living condition. At each visit, urine osmolality (UOSM), urine specific gravity (USG), urine color (UCOL), body mass loss (BML), thirst, and plasma osmolality (POSM) were collected and analyzed. The participants recorded their food and fluid intake between the visits to determine TWI-MA. Linear regression was used to predict the effect of morning thirst on the afternoon hydration indices for all the participants, as well as for males and females separately. Results: Higher morning thirst predicted lower UOSM (r2 = 0.056, p = 0.045), USG (r2 = 0.096, p = 0.008), UCOL (r2 = 0.074, p = 0.021), and higher thirst (r2 = 0.074, p = 0.021) in the afternoon. However, morning thirst did not predict afternoon BML, POSM, or TWI-MA (p &gt; 0.05). In males, higher morning thirst predicted lower afternoon UOSM (r2 = 0.130, p = 0.031) and USG (r2 = 0.153, p = 0.018). Additionally, higher morning thirst predicted higher TWI-MA (r2 = 0.154, p = 0.018) in females. Conclusions: Morning thirst had a negligible impact on later hydration status, specifically with afternoon urine indices. Furthermore, higher thirst sensation did not impact BML, POSM, or TWI-MA. However, thirst sensation minimally contributed to drinking behavior in females. Overall, individuals may not rely solely on thirst sensation to manipulate their drinking behavior to optimize their fluid balance during their daily lives due to the complexity of thirst mechanisms.<\/jats:p>","DOI":"10.3390\/nu16183212","type":"journal-article","created":{"date-parts":[[2024,9,23]],"date-time":"2024-09-23T09:15:07Z","timestamp":1727082907000},"page":"3212","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Relationships between Morning Thirst and Later Hydration Status and Total Water Intake"],"prefix":"10.3390","volume":"16","author":[{"given":"Kelly B.","family":"Elliott","sequence":"first","affiliation":[{"name":"Sports Performance Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcos S.","family":"Keefe","sequence":"additional","affiliation":[{"name":"Sports Performance Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan-Joseph S.","family":"Rolloque","sequence":"additional","affiliation":[{"name":"Sports Performance Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3583-7615","authenticated-orcid":false,"given":"Nigel C.","family":"Jiwan","sequence":"additional","affiliation":[{"name":"Applied Physiology Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan A.","family":"Dunn","sequence":"additional","affiliation":[{"name":"Sports Performance Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui-Ying","family":"Luk","sequence":"additional","affiliation":[{"name":"Applied Physiology Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yasuki","family":"Sekiguchi","sequence":"additional","affiliation":[{"name":"Sports Performance Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,23]]},"reference":[{"key":"ref_1","unstructured":"Taylor, K., and Jones, E.B. (2024). Adult Dehydration, StatPearls Publishing."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1007\/s00394-022-02972-2","article-title":"Total Water Intake Guidelines Are Sufficient for Optimal Hydration in United States Adults","volume":"62","author":"Seal","year":"2023","journal-title":"Eur. J. Nutr."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1038\/ejcn.2009.111","article-title":"Water as an Essential Nutrient: The Physiological Basis of Hydration","volume":"64","author":"Constant","year":"2010","journal-title":"Eur. J. Clin. Nutr."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1042\/bj3130697","article-title":"The Role of Cellular Hydration in the Regulation of Cell Function","volume":"313","year":"1996","journal-title":"Biochem. J."},{"key":"ref_5","first-page":"1","article-title":"The Physiological Regulation of Thirst and Fluid Intake","volume":"19","author":"McKinley","year":"2004","journal-title":"News Physiol. Sci. Int. J. Physiol. Prod. Jointly Int. Union Physiol. Sci. Am. Physiol. Soc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"700","DOI":"10.1016\/j.physbeh.2008.04.007","article-title":"Relationships between Human Thirst, Hunger, Drinking, and Feeding","volume":"94","author":"McKiernan","year":"2008","journal-title":"Physiol. Behav."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Armstrong, L.E., and Kavouras, S.A. (2019). Thirst and Drinking Paradigms: Evolution from Single Factor Effects to Brainwide Dynamic Networks. Nutrients, 11.","DOI":"10.3390\/nu11122864"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"S97","DOI":"10.1007\/s40279-014-0155-0","article-title":"The Interrelationship of Research in the Laboratory and the Field to Assess Hydration Status and Determine Mechanisms Involved in Water Regulation during Physical Activity","volume":"44","author":"Stachenfeld","year":"2014","journal-title":"Sports Med. Auckl. N. Z."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Armstrong, L.E., Giersch, G.E.W., Dunn, L., Fiol, A., Mu\u00f1oz, C.X., and Lee, E.C. (2020). Inputs to Thirst and Drinking during Water Restriction and Rehydration. Nutrients, 12.","DOI":"10.3390\/nu12092554"},{"key":"ref_10","first-page":"R1740","article-title":"Regulation of Fluid Intake in Dehydrated Humans: Role of Oropharyngeal Stimulation","volume":"272","author":"Figaro","year":"1997","journal-title":"Am. J. Physiol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"460","DOI":"10.1038\/ki.1984.39","article-title":"Abnormalities of Thirst Regulation","volume":"25","author":"Robertson","year":"1984","journal-title":"Kidney Int."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"566","DOI":"10.1177\/19417381211038494","article-title":"Relationships Between WUT (Body Weight, Urine Color, and Thirst Level) Criteria and Urine Indices of Hydration Status","volume":"14","author":"Sekiguchi","year":"2022","journal-title":"Sports Health"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"532","DOI":"10.1123\/ijsnem.14.5.532","article-title":"Daily Body Mass Variability and Stability in Active Men Undergoing Exercise-Heat Stress","volume":"14","author":"Cheuvront","year":"2004","journal-title":"Int. J. Sport Nutr. Exerc. Metab."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"American College of Sports Medicine, Sawka, M.N., Burke, L.M., Eichner, E.R., Maughan, R.J., Montain, S.J., and Stachenfeld, N.S. (2007). American College of Sports Medicine Position Stand. Exercise and Fluid Replacement. Med. Sci. Sports Exerc., 39, 377\u2013390.","DOI":"10.1016\/S0162-0908(08)70206-X"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1123\/ijsn.4.3.265","article-title":"Urinary Indices of Hydration Status","volume":"4","author":"Armstrong","year":"1994","journal-title":"Int. J. Sport Nutr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1016\/0031-9384(87)90212-5","article-title":"Thirst and Fluid Intake Following Graded Hypohydration Levels in Humans","volume":"40","author":"Engell","year":"1987","journal-title":"Physiol. Behav."},{"key":"ref_17","first-page":"21","article-title":"Estimating the Size of Treatment Effects","volume":"6","author":"McGough","year":"2009","journal-title":"Psychiatry Edgmont"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Surapongchai, J., Saengsirisuwan, V., Rollo, I., Randell, R.K., Nithitsuttibuta, K., Sainiyom, P., Leow, C.H.W., and Lee, J.K.W. (2021). Hydration Status, Fluid Intake, Sweat Rate, and Sweat Sodium Concentration in Recreational Tropical Native Runners. Nutrients, 13.","DOI":"10.3390\/nu13041374"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Adams, W.M., Vandermark, L.W., Belval, L.N., and Casa, D.J. (2019). The Utility of Thirst as a Measure of Hydration Status Following Exercise-Induced Dehydration. Nutrients, 11.","DOI":"10.3390\/nu11112689"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1007\/s00394-018-01889-z","article-title":"Hydration, Dehydration, Underhydration, Optimal Hydration: Are We Barking up the Wrong Tree?","volume":"58","author":"Kavouras","year":"2019","journal-title":"Eur. J. Nutr."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1038\/s41586-019-1066-x","article-title":"A Gut-to-Brain Signal of Fluid Osmolarity Controls Thirst Satiation","volume":"568","author":"Zimmerman","year":"2019","journal-title":"Nature"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1126\/science.aav3932","article-title":"Thirst Regulates Motivated Behavior through Modulation of Brainwide Neural Population Dynamics","volume":"364","author":"Allen","year":"2019","journal-title":"Science"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1016\/0031-9384(88)90367-8","article-title":"A Microregulatory Analysis of Spontaneous Fluid Intake by Humans: Evidence That the Amount of Liquid Ingested and Its Timing Is Mainly Governed by Feeding","volume":"43","year":"1988","journal-title":"Physiol. Behav."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"113211","DOI":"10.1016\/j.physbeh.2020.113211","article-title":"Progression of Human Subjective Perceptions during Euhydration, Mild Dehydration, and Drinking","volume":"229","author":"Armstrong","year":"2021","journal-title":"Physiol. Behav."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1016\/j.neuron.2016.08.032","article-title":"Hunger-Driven Motivational State Competition","volume":"92","author":"Burnett","year":"2016","journal-title":"Neuron"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Adams, W.M., Hevel, D.J., Maher, J.P., and McGuirt, J.T. (2020). Racial and Sex Differences in 24 Hour Urinary Hydration Markers among Male and Female Emerging Adults: A Pilot Study. Nutrients, 12.","DOI":"10.3390\/nu12041068"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.1016\/0022-4731(77)90063-2","article-title":"Distribution of Androgen Target Cells in Rat Forebrain and Pituitary after [3H]-Dihydrotestosterone Administration","volume":"8","author":"Sar","year":"1977","journal-title":"J. Steroid Biochem."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1016\/0304-3940(80)90081-6","article-title":"Simultaneous Localization of [3H]Estradiol and Neurophysin I or Arginine Vasopressin in Hypothalamic Neurons Demonstrated by a Combined Technique of Dry-Mount Autoradiography and Immunohistochemistry","volume":"17","author":"Sar","year":"1980","journal-title":"Neurosci. Lett."},{"key":"ref_29","first-page":"R187","article-title":"Estrogen Influences Osmotic Secretion of AVP and Body Water Balance in Postmenopausal Women","volume":"274","author":"Stachenfeld","year":"1998","journal-title":"Am. J. Physiol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1097\/JES.0b013e31817be928","article-title":"Sex Hormone Effects on Body Fluid Regulation","volume":"36","author":"Stachenfeld","year":"2008","journal-title":"Exerc. Sport Sci. Rev."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1111\/j.1365-2265.1985.tb01062.x","article-title":"Variation in Osmoregulation of Arginine Vasopressin during the Human Menstrual Cycle","volume":"22","author":"Spruce","year":"1985","journal-title":"Clin. Endocrinol."},{"key":"ref_32","first-page":"E607","article-title":"Osmoregulation of Thirst and Vasopressin Secretion in Human Subjects: Effect of Various Solutes","volume":"244","author":"Zerbe","year":"1983","journal-title":"Am. J. Physiol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"904","DOI":"10.1038\/ejcn.2015.217","article-title":"Equivalence of Afternoon Spot and 24-h Urinary Hydration Biomarkers in Free-Living Healthy Adults","volume":"70","author":"Bottin","year":"2016","journal-title":"Eur. J. Clin. Nutr."}],"container-title":["Nutrients"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6643\/16\/18\/3212\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:02:30Z","timestamp":1760112150000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6643\/16\/18\/3212"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,9,23]]},"references-count":33,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2024,9]]}},"alternative-id":["nu16183212"],"URL":"https:\/\/doi.org\/10.3390\/nu16183212","relation":{},"ISSN":["2072-6643"],"issn-type":[{"value":"2072-6643","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,9,23]]}}}