_-_Thirst_(1886).jpg)
Thirst is the craving for potable fluids, resulting in the basic instinct of animals to drink. It is an essential mechanism involved in fluid balance.[1] It arises from a lack of fluids or an increase in the concentration of certain osmolites, such as sodium. If the water volume of the body falls below a certain threshold or the osmolite concentration becomes too high, structures in the brain detect changes in blood constituents and signal thirst.[2]
Continuous dehydration can cause acute and chronic diseases, but is most often associated with renal and neurological disorders.[1] Excessive thirst, called polydipsia, along with excessive urination, known as polyuria, may be an indication of diabetes mellitus or diabetes insipidus.
There are receptors and other systems in the body that detect a decreased volume or an increased osmolite concentration.[1][2] Some sources distinguish "extracellular thirst" from "intracellular thirst", where extracellular thirst is thirst generated by decreased volume and intracellular thirst is thirst generated by increased osmolite concentration.[2]
- ^ a b c Stanhewicz, Anna E.; Larry Kenney, W. (2015-08-19). "Determinants of water and sodium intake and output". Nutrition Reviews. 73 (suppl 2): 73–82. doi:10.1093/nutrit/nuv033. ISSN 0029-6643. PMID 26290293.
- ^ a b c McKinley, Michael J.; Denton, Derek A.; Ryan, Philip J.; Yao, Song T.; Stefanidis, Aneta; Oldfield, Brian J. (2019-03-14). "From sensory circumventricular organs to cerebral cortex: Neural pathways controlling thirst and hunger". Journal of Neuroendocrinology. 31 (3): e12689. doi:10.1111/jne.12689. hdl:11343/285537. ISSN 0953-8194. PMID 30672620. S2CID 58947441.