Editing Drinking (section)

==Hydration and dehydration==
{{Main|Tissue hydration|Dehydration}}
Like nearly all other life forms, humans require water for [[tissue hydration]]. Lack of hydration causes [[thirst]], a desire to drink which is regulated by the [[hypothalamus]] in response to subtle changes in the body's [[electrolyte]] levels and blood volume. A decline in total [[body water]] is called [[dehydration]] and will eventually lead to death by [[hypernatremia]]. Methods used in the [[management of dehydration]] include assisted drinking or [[oral rehydration therapy]].

An overconsumption of water can lead to [[water intoxication]], which can dangerously dilute the concentration of salts in the body. Overhydration sometimes occurs among athletes and outdoor laborers, but it can also be a sign of disease or damage to the hypothalamus. A persistent desire to drink inordinate quantities of water is a psychological condition termed [[polydipsia]]. It is often accompanied by [[polyuria]] and may itself be a symptom of [[diabetes mellitus]] or [[diabetes insipidus]].<ref name=Provan120>Provan, p. 129.</ref>

===Human water requirements===
[[File:ISS014-E-08330 (27 Nov. 2006) --- European Space Agency (ESA) astronaut Thomas Reiter.jpg|thumb|Astronaut [[Thomas Reiter]] during [[Expedition 14]] drinking water on the [[International Space Station]]|alt=refer to caption]]
A daily intake of water is required for the normal physiological functioning of the [[human body]]. The [[United States Department of Agriculture|USDA]] recommends a daily intake of ''total water'': not necessarily by drinking but by consumption of water contained in other [[beverage]]s and foods. The recommended intake is 3.7 liters (appx. 1 gallon) per day for an adult male, and 2.7 liters (appx. 0.75 gallon) for an adult female.<ref name=USDA2011>
{{cite book |last=Institute of Medicine |author-link=National Academy of Medicine |date=2005 |title=Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. |url=https://nap.nationalacademies.org/read/10925/chapter/6 |location=Washington, DC |publisher=The National Academies Press |page=73 |isbn=978-0-309-13335-7}}</ref>

Other sources, however, claim that a high intake of fresh [[drinking water]], separate and distinct from other sources of moisture, is necessary for good health – eight servings per day of eight fluid ounces (1.8 liters, or 0.5 gallon) is the amount recommended by many [[nutritionist]]s,<ref name="bbc">{{Cite web |url=https://www.bbc.co.uk/health/treatments/healthy_living/nutrition/healthy_water.shtml |title=Healthy living – Water |language=English |access-date=1 January 2022 |archive-url=https://web.archive.org/web/20130408071634/http://www.bbc.co.uk/health/treatments/healthy_living/nutrition/healthy_water.shtml |archive-date=8 April 2013 |url-status=dead |author=Greenhalgh, Alison |year=2001 |publisher=[[BBC]] |work=BBC Health}}</ref> although there is no scientific evidence supporting this recommendation.<ref>{{Cite journal |title=Drink at least eight glasses of water a day: Really? Is there scientific evidence for "8 × 8"? |journal=American Journal of Physiology. Regulatory, Integrative and Comparative Physiology |volume=283 |issue=5 |pages=R993–R1004 |author1=Valtin, Heinz |author2=Gorman, Sheila A. |year=2012 |df=dmy-all |doi=10.1152/ajpregu.00365.2002 |pmid=12376390 }}</ref><ref name=JASN2008>{{Cite journal |author1=Negoianu, Dan |author2=Goldfarb, Stanley |title=Just Add Water |journal=Journal of the American Society of Nephrology |publisher=[[American Society of Nephrology|ASN]] |volume=19 |issue=6 |pages=1041–1043 |year=2008 |doi=10.1681/ASN.2008030274 |pmid=18385417 |doi-access=free }}</ref>

Evidence-based hydration experts say that the amount of drinking water needed depends on ambient temperature, activity level, body size, and sweat rate.<ref name="lifekit">[https://www.npr.org/2022/09/22/1124590408/how-much-water-do-you-actually-need-heres-the-science How much water do you actually need? Here's the science]</ref> Research shows drinking when thirsty will maintain hydration to within about 2% of the needed level.<ref name="lifekit" /> Drinking beyond thirst might be beneficial for people who need to perform tasks that require intense concentration, and those with [[kidney disease]], [[kidney stones]], [[urinary tract infection]]s, and people with a weak sense of thirst (which may include more older people).<ref name="lifekit" />