A dry mouth, an afternoon headache, concentration slipping away: dehydration rarely starts dramatically. In a trial conducted on 25 young women, a loss of just 1.36% of body weight was enough to worsen mood and cause headaches. In older adults, it often goes unnoticed, affecting as many as one in five residents in a nursing home study.
This guide brings together what studies identified via PubMed show, from the first signs to emergency situations.
Signs and causes : thirst, fatigue, headaches, reduced concentration and infrequent dark urine appear from 1 to 2% of body weight lost as water. Beyond 2%, attention decreases further; a meta-analysis quantifies muscle endurance loss at 8.3%. In older adults, thirst and urine color are often misleading.
Rehydrating : drinking more than what was lost, with sodium from a meal or beverage, allows the body to retain water. In case of diarrhea, especially in children, the oral rehydration solution from the pharmacy remains the gold standard. Confusion, drowsiness, absence of urine or an infant no longer drinking require urgent medical attention.
- Dehydration: what are we talking about?
- The first signs: thirst, fatigue, headaches
- Concentration and performance: what changes beyond 2%
- Urine, thirst, weight: signs that are more or less reliable
- The causes: heat, illness, medications, coffee and alcohol
- Older adults: a dulled sense of thirst
- Infants and children: recognizing and rehydrating
- Rehydrating: water, volume and sodium
- Rehydrating quickly: step-by-step plan
- Drinking regularly every day
- Drinking too much, and signs that require calling emergency services
- Frequently asked questions
Dehydration: What are we talking about?
Being dehydrated means having lost more water than you have taken in. Brought together in 2019 using a consensus method, twelve experts nonetheless found that there is no universally accepted definition. They distinguish two situations. Dehydration from water loss, the most common when you don't drink enough, concentrates the blood: its osmolality, its concentration of dissolved particles, increases. Beyond 300 mOsm per kilogram, a person is said to be hyperosmolar, and direct measurement of plasma osmolality is the reference method. Loss of water and salt, typical of diarrhea and vomiting, mainly reduces the volume of circulating blood, what doctors call hypovolemia, without necessarily concentrating the blood.
These experts emphasize that outside extreme cases, signs of dehydration in adults are subtle and unreliable. In a healthy person, total body water fluctuates from day to day by 600 to 900 ml, or less than 1% of body weight. Researchers therefore express dehydration as a percentage of body weight lost as water. For a 70 kg person, 1% represents 0.7 liters and 2% represents 1.4 liters (editorial calculation).
First signs: thirst, fatigue, headaches
Thirst is the first signal, but it doesn't increase indefinitely. In 15 volunteers deprived of beverages for 37 hours, body weight decreased by 2.7% and plasma volume by 6.2%; thirst increased during the first 13 hours, then plateaued. Participants reported headaches, reduced concentration capacity, and decreased alertness.
In 25 young women, intermittent walking with or without a diuretic caused water loss of 1.36% of body weight on average. Compared to well-hydrated days, this mild dehydration degraded mood, increased fatigue and perceived task difficulty, reduced concentration, and caused headaches. Most intellectual performance tests, by contrast, were not affected.
Armstrong LE, Ganio MS, Casa DJ, et al. J Nutr 2012;142(2):382-388. DOI: 10.3945/jn.111.142000
In 26 young men tested using the same protocol, a weight loss of 1.59% increased errors on a visual vigilance test and slowed working memory, with more fatigue, tension, and anxiety. Both of these small trials were not designed to compare sexes. Both were funded by the research department of a food industry group.
Water-related headache was described based on a descriptive survey with weak level of evidence: approximately one in ten people surveyed reported suffering from it. Among 34 affected individuals, 22 experienced relief within 30 minutes after drinking between 200 and 1,500 ml, averaging 500 ml, and 11 within one to three hours.
Concentration and performance: what changes beyond 2%
A meta-analysis of 33 studies, comprising 413 participants dehydrated by 1 to 6% of their body weight, quantifies the effect on intellectual performance in effect size, where 0.2 corresponds to a small effect, 0.5 to a medium effect, and 0.8 to a large effect. The overall effect is small (−0.21), but it reaches −0.52, a medium effect, onattention, and −0.40 on motor coordination; simple reaction time is not significantly affected. The effect is more pronounced beyond 2% weight loss (−0.28) than below it (−0.14, at the threshold of statistical significance).
On the muscle side, a meta-analysis of 28 publications measures a decline of 8.3% inmuscular endurance, 5.5% in strength, and 5.8% in anaerobic power; anaerobic capacity (−3.5%) and vertical jump (+0.9%) are not significantly altered. Trained individuals appeared less affected, without significant difference.
In endurance, in a meta-analysis of 5 studies comprising 39 cyclists in time trials, an average weight loss of 2.20% did not alter performance (+0.06%, non-significant), and drinking according to thirst produced better results than drinking less (+5.2%). A second analysis of 15 publications and 122 participants confirms: in time trials, dehydration up to 4% did not reduce performance (+0.09%), whereas at imposed intensity, it reduced it by 1.91%. In recreational running, from 5 to 42 km, estimated losses remain under 2%.
Urine, thirst, weight: signs more or less reliable
In young, active adults, the color of urine is an honest indicator: in three studies, it was strongly correlated with urinary density and osmolality, measured in the laboratory. A pooled analysis of 238 adults, conducted in part by the research department of a food industry group, quantified this link: lightening urine by two shades on an eight-point scale required drinking approximately 1.1 liters more per day. Two physiology researchers propose combining three markers: first morning urine, morning weight, and thirst.
In people aged 65 and older, 67 signs and tests were compared against reference blood tests, based on 24 studies. None were consistently useful. Thirst, dry mouth, urine color, density and volume, heart rate, or fluid intake should not be used alone. Two signs showed promise in a study of 71 people: missing drinks between meals and reporting fatigue; together, they identified 71% of dehydrated individuals, with 92% specificity.
Hooper L, Abdelhamid A, Attreed NJ, et al. Cochrane Database Syst Rev 2015;(4):CD009647. DOI : 10.1002/14651858.CD009647.pub2
Similar findings in hospitals: in 130 people averaging 78 years old, the seven physical signs tested, including dry mouth and skin turgor, had sensitivity ranging from 0 to 44%, and urine color performed no better than chance. Saliva osmolality, a measure still not widely used, identified 70 to 78% of dehydrated individuals depending on type, with specificity of 68 to 72%.
| Sign | What studies show | Reliability (editorial assessment) |
|---|---|---|
| Thirst | Plateaus after 13 hours of deprivation in adults; diminished after age 65 | Moderate in adults, weak after age 65 |
| Urine color | Correlated with urine density and osmolality in adults; non-discriminating after age 65 | Good in active adults, weak after age 65 |
| Morning weight | Benchmark suggested with morning urine and thirst | Good for tracking recent weight loss |
| Dry mouth, skin turgor, pulse | Sensitivity of 0 to 44% in elderly individuals | Weak in isolation |
| Capillary refill, skin turgor, respiratory rate (young child) | Best isolated signs; three signs combined identify 87% of dehydrated children | Moderate alone, good in combination |
| Blood test (osmolality) | Reference standard method | Medical reference |
The causes: heat, illness, medications, coffee and alcohol
General medical concept: dehydration results from an imbalance between what is lost and what is taken in. Losses increase with heat and exertion, diarrhea and vomiting, which cause loss of water and salt, and fever ; uncontrolled diabetes also increases urination. Intake decreases with illness, dependence, or when thirst diminishes with age.
<<<38>>> Medications médicaments also play a role. In an analysis of 6,700 hospitalized Australian veterans for dehydration or heat-related illness, hospitalization risk increased after starting an anticoagulant, cardiovascular medication, nonsteroidal anti-inflammatory drug, antipsychotic, antidepressant, or anticholinergic: from 1.17 times for serotonin reuptake inhibitor antidepressants to 2.79 times for the combination of an ACE inhibitor and a diuretic, two blood pressure treatments. No link was found for anticonvulsants, antiparkinsonian drugs, sedatives, anxiolytics, and antihistamines. These are associations, and medication should never be stopped without medical advice: during periods of heat, consult your doctor or pharmacist.
The coffee is largely ruled out at usual doses. In 50 men who normally drink 3 to 6 cups per day, four 200 ml cups providing 4 mg of caffeine per kilogram, or 308 mg per day on average, did not cause more dehydration than the same amount of water over three days: body water and 24-hour urine volume were comparable, 2,409 versus 2,428 ml. The trial was funded by a scientific information institute on coffee. For reference, a dose of our Pre Workout Booster provides 200 mg of caffeine; the trial involved coffee in habitual drinkers, and its results do not apply to a supplement. Our article how much coffee per day reviews reasonable amounts.
As foralcohol, the effect remains mild at moderate quantities. In 20 men aged 60 to 75, 30 g of alcohol consumed at lunch in the form of wine or spirits increased urine volume over 4 hours compared to non-alcoholic equivalents, but not over 24 hours; in beer form, no difference. The difference between the three beverages was not statistically significant. The trial was conducted by a research institute linked to the brewing sector and says nothing about larger quantities.
Elderly persons: a weakened thirst
In 1984, after 24 hours without drinking, 7 men aged 67 to 75 in good health had more concentrated blood than 7 men aged 20 to 31 who had lost the same amount of weight; yet they felt less thirsty and drank less, so their blood did not return to its initial state. Their kidneys also concentrated urine less effectively.
In a nursing home, the DRIE study measured blood osmolality in 188 residents with an average age of 86: 20% were dehydrated. Cognitive disorders, kidney function, and diabetes were associated with it, and thirst had no link to hydration status. In the hospital, of 6,632 emergency admissions of people aged 65 and over, 27% presented with hyperosmolar dehydration; after adjustment, these patients had 4.5 times greater risk of acute kidney injury and 30-day mortality was 60% higher. This is a retrospective study: dehydration may be a marker of severity as much as a cause.
In a review of 23 studies in residential facilities, 6 of the 9 combined interventions improved fluid intake or reduced dehydration: a wider choice of beverages within reach, staff training, assistance with drinking and using the toilet. These studies remain of limited quality.
Offer varied beverages at regular times, including between meals, and be alert to unusual fatigue, confusion, or less frequent urination. These are practical tips, not trial results.
Infants and children: recognize and rehydrate
In children from one month to five years old, a review of 13 studies identified the three most useful isolated signs for detecting a loss of at least 5% of body weight: prolonged capillary refill time (after pressing the fingertip, the skin remains pale longer), a persistent skin fold and abnormal breathing. In the emergency department, in 186 children of the same age with diarrhea, vomiting, or poor fluid intake, at least three signs combined identified 87% of children dehydrated by at least 5%, with 82% specificity. Four signs performed as well as the entire set: capillary refill time exceeding 2 seconds, absence of tears, dry mouth and tongue, altered general appearance. Fewer wet diapers were a sensitive but non-specific signal.
The oral rehydration solution sold in pharmacies is the standard. European pediatric recommendations from 2014 make it the primary treatment for gastroenteritis, starting as early as possible, without interrupting breastfeeding or feeding. A review of 17 trials and 1,811 children compared it to intravenous therapy: the oral route failed slightly more often (4% difference, or approximately one child in 25 subsequently switched to intravenous), and hospital stay was 1.2 days shorter. Compared to the original formulation, reduced-osmolarity solutions reduced the need for unexpected intravenous therapy in 9 trials (odds ratio 0.61) as well as vomiting, without increased hyponatremia.
In 647 children aged 6 months to 5 years with mild gastroenteritis and little or no dehydration, half-diluted apple juice followed by the child's preferred beverages led to fewer treatment failures than an electrolyte solution: 16.7% versus 25.0%, and 2.5% intravenous therapy versus 9.0%. Hospitalizations and frequency of diarrhea and vomiting did not differ. This result applies to mild cases in a high-income country, not to significantly dehydrated children.
Freedman SB, Willan AR, Boutis K, Schuh S. JAMA 2016;315(18):1966-1974. DOI: 10.1001/jama.2016.5352
Our Electrolytes are formulated for adults: they should be kept out of reach of young children and do not replace an oral rehydration solution. In infants and young children, rehydration is done with the pharmacy solution in small repeated amounts, and a doctor should be consulted as soon as signs of dehydration appear.
Rehydrating: water, volume, and sodium
After significant water loss, water alone is not always enough because the kidneys quickly eliminate the excess. In 12 men dehydrated by 2% of their body weight through cycling exercise, drinking 50, 100, 150, or 200% of the lost volume showed that one must drink more than what was lost, and that without enough sodium in the drink, this extra amount is mostly eliminated in the urine. The tested beverages contained 23 or 61 mmol of sodium per liter.
Six dehydrated men, depleted by 1.9% of their body weight through heat-induced exertion, drank 1.5 times the lost volume in 30 minutes, approximately 2 liters, of a beverage containing 2, 26, 52, or 100 mmol of sodium per liter. The saltier the drink, the less they urinated. At the end of the trial, they remained in deficit of 689 ml with the nearly sodium-free beverage and 359 ml at 26 mmol per liter, while they had regained their balance at 52 mmol per liter (−2 ml) and at 100 mmol per liter (+98 ml).
Maughan RJ, Leiper JB. Eur J Appl Physiol Occup Physiol 1995;71(4):311-319. DOI : 10.1007/BF00240410
Sodium can also come from your meal. In 8 dehydrated volunteers depleted by 2.1%, a meal accompanied by a nearly salt-free beverage restored balance in 6 hours (−29 ml), compared to a deficit of 373 ml with a sports drink containing 21 mmol of sodium per liter. Milk is also well retained: in 11 people dehydrated by 1.8%, low-fat milk produced 611 ml of urine in 5 hours, compared to 1,184 ml for water and 1,205 ml for a sports drink, at equal volume, except in cases of lactose intolerance. In 72 non-dehydrated men, a trial funded by a hydration institute co-founded by a beverage group compared 13 common drinks, at one liter per beverage: oral rehydration solution and milk were better retained than water; coffee, tea, soft drinks, light beer, and a sports drink did not differ from water.
| Beverage | Results in trials | Level of evidence (editorial assessment) |
|---|---|---|
| Nearly sodium-free beverage, 1.5 times the loss | Deficit of 689 ml at end of trial | One trial of 6 men |
| 26 mmol of sodium per liter | Deficit of 359 ml | One trial of 6 men |
| 52 or 100 mmol of sodium per liter | Balance restored (−2 ml and +98 ml) | One trial of 6 men |
| Meal and low-salt beverage | Balance in 6 hours | One trial of 8 volunteers |
| Milk | Fewer urines than water, twice less after dehydration | Two concordant trials |
| Oral rehydration solution | Better retained than water; reference in case of diarrhea | Solid in children |
| Coffee, tea, soft drinks, light beer, sports drink | No more urine than water over 4 hours | One trial of 72 men |
Where do our Electrolytes stand? One tablet provides 300 mg of sodium, approximately 13 mmol, which gives 26 mmol per liter in 500 ml of water and 52 in 250 ml (editorial calculation). The total quantity differs: participants had drunk approximately 2 liters at 52 mmol per liter, or approximately 106 mmol or 2,440 mg of sodium, when a maximum of two tablets daily provide 600 mg, approximately one quarter. No trial has tested our tablets: these figures establish their sodium content without predicting an effect. Our analysis of electrolytes details their benefits during exercise according to studies.
Rehydrate quickly: the step-by-step plan
Why does oral rehydration solution work so well in case of diarrhea? Because glucose carries sodium with it, and therefore water, across the small intestine wall, through a mechanism that continues to function during infectious diarrhea.
Our Electrolytes address other situations for adults: a workout session, a day of intense heat, a trip. They provide 1 g of glucose per two tablets and contain polyols, excess of which can have a laxative effect; in case of diarrhea, an oral rehydration solution from a pharmacy is better suited.
How long does it take? The trials monitored fluid balance 5 to 7.5 hours after exercise; with sufficient volume and sodium, balance was restored within this timeframe. Significant dehydration or dehydration related to illness requires more time, and sometimes an IV infusion.
Two tablets provide 1.5 g of salt: consult a healthcare professional in case of a low-salt diet, medical treatment, including high blood pressure treatment, or kidney or heart problems. No more than two tablets per day. They are not recommended for pregnant or breastfeeding women, should be kept out of reach of young children, and may contain traces of gluten, soy, and milk.
Drink regularly every day
The advice to drink at least eight glasses of water a day is not based on any study, according to a 2002 review that searched for its origin. In healthy sedentary adults in a temperate climate, caffeinated beverages count toward the total, and large quantities are mainly justified in case of exercise, heat, or certain diseases. The color of urine remains the simplest guideline for adjustment. In case of kidney or heart disease, the amount to drink should be decided with a doctor. In 631 adults with moderate chronic kidney disease, coaching to drink more did not slow the decline in kidney function over one year, in a trial that may have been too small to show it.
In 102 patients suffering from recurrent headaches and drinking less than 2.5 liters per day, the instruction to drink 1.5 liters of additional water per day for 3 months improved a migraine-related quality of life score by 4.5 points, and 47% of participants in the water group reported a marked improvement, compared to 25% in the control group. The number of days with at least moderate headache, however, did not change noticeably.
Spigt M, Weerkamp N, Troost J, et al. Fam Pract 2012;29(4):370-375. DOI: 10.1093/fampra/cmr112
Practical tip: a 500 ml water bottle within reach provides a simple way to track what you drink; it's best not to keep liquid in it for more than 24 hours.
Drinking too much, and the signs that require calling emergency services
When we drink significantly more than what we lose, the sodium in the blood becomes diluted: this ishyponatremia, notably described during prolonged exertion.
Among 488 runners from an American urban marathon sampled at the finish line, 13% had hyponatremia, with a blood sodium level of 135 mmol per liter or less, and 0.6% had critical hyponatremia, at 120 mmol per liter or less. Associated factors were weight gain during the race, indicative of fluid intake exceeding losses (odds ratio of 4.2), race time exceeding 4 hours (7.4, compared to less than 3 hours 30 minutes), and very low or very high body mass index. Beverage composition was not associated with it.
Almond CS, Shin AY, Fortescue EB, et al. N Engl J Med 2005;352(15):1550-1556. DOI: 10.1056/NEJMoa043901
In this observational study, beverage composition was not linked to risk, contrary to weight gain: not finishing a prolonged exertion heavier than at the start remains the most meaningful indicator.
These general medical recommendations do not come from a study. Infant or young child : refuses to drink or vomits everything, diapers remain dry, is drowsy or limp, cries without tears, eyes or fontanelle (top of the skull) appear sunken, skin is mottled, breathes rapidly or abnormally. Elderly person : unusual confusion or disorientation, drowsiness, falls or lightheadedness, increased urination or very infrequent and dark urine, inability to drink. At any age : lightheadedness or loss of consciousness, very rapid pulse, vomiting that prevents drinking, bloody diarrhea, high fever, seizures, absence of urination for many hours. After prolonged exertion, nausea, headache, confusion, or vomiting in someone who has drunk a lot may signal hyponatremia: do not give them more water to drink and call emergency services.
Without signs of severity, prompt medical advice is still recommended when diarrhea, vomiting, or fever persists, in pregnant women, people with diabetes or taking diuretics, and in infants.
Effervescent tablets with lime flavor, in a tube of 20 tablets, for 10 days at 2 tablets per day. Each tablet provides 300 mg of sodium; dissolved in at least 200 ml of water, it supports the adult during a sports session, intense heat, or travel.
View ElectrolytesTo keep fresh water within reach, discover our NP 500 ml insulated water bottle.
Frequently Asked Questions
What are the symptoms of dehydration?
The first signs are thirst, fatigue, headaches, decreased concentration, dry mouth, and infrequent and dark urine. Confusion, drowsiness, lightheadedness, and absence of urination are signs of severity requiring urgent medical attention.
How do you know if you are dehydrated?
In a healthy adult, three indicators complement each other: the color of the first morning urine, morning weight, and the sensation of thirst. In elderly people, these signs are often misleading, and only a blood test measuring osmolality can confirm dehydration.
How do you rehydrate quickly?
By drinking small sips of a volume greater than what was lost, with sodium provided through a meal or beverage. In case of diarrhea, pharmacy oral rehydration solution is the standard.
Dehydration: what to do?
Cool down, drink in small regular amounts and eat normally salted food; in case of diarrhea or vomiting, use an oral rehydration solution. Call 15 or 112 in case of confusion, drowsiness, lightheadedness, absence of urination, or inability to drink, and consult promptly for an infant or elderly person.
What are the signs of dehydration in elderly people?
They are subtle: fatigue, drinks left aside between meals, confusion, drowsiness, falls, less frequent urination. Thirst and urine color are not reliable after age 65: in a nursing home study, 20% of residents were dehydrated and thirst had no correlation with their hydration status.
What are the signs of dehydration in babies?
Skin that is slow to regain color after pressure, a skin fold that persists, abnormal breathing, absence of tears, dry mouth, and overall altered appearance. At least three combined signs identified 87% of dehydrated children in a study. An infant who drinks poorly, vomits, or is drowsy should be examined urgently.
Is urine color a good indicator?
In an active, healthy adult, yes, as a practical indicator: it is strongly correlated with urine concentration measured in the laboratory, and lightening urine by two shades corresponded to approximately 1.1 liters of additional fluid consumed per day. In elderly people, however, it does not allow distinguishing between dehydrated and non-dehydrated individuals.
Does coffee dehydrate you?
Not at usual doses in regular drinkers. In a trial of 50 men, four cups per day did not dehydrate more than the same amount of water.
Is water alone enough to rehydrate?
For minor fluid loss, yes, especially with a meal, which provides the sodium needed to retain water. After more significant loss, water alone is partly eliminated in urine: in trials, milk, oral rehydration solution, and sodium-rich beverages were better retained.
Should you drink 1.5 liters or 8 glasses of water per day?
No study justifies a single number for everyone, according to a review that investigated the origin of the eight-glass recommendation. Needs depend on heat, exercise, and health status, and all beverages count, including coffee and tea.
Can you drink too much water?
Yes. At a marathon finish line, 13% of tested runners had blood sodium levels that were too low, hyponatremia, associated mainly with weight gain during the race. Nausea, headaches, confusion, or vomiting after drinking heavily require calling emergency services.
When should you go to the emergency room for dehydration?
Call 911 in case of confusion, drowsiness, dizziness or loss of consciousness, absence of urination, vomiting that prevents drinking, or diarrhea with blood. In infants, refusing to drink, dry diapers, a sunken fontanel, or lethargy are emergency signs.
Sources
The studies cited below were identified via PubMed.
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- Armstrong LE, Ganio MS, Casa DJ, et al. Mild dehydration affects mood in healthy young women. The Journal of Nutrition, 2012;142(2):382-388. DOI
- Ganio MS, Armstrong LE, Casa DJ, et al. Mild dehydration impairs cognitive performance and mood in men. The British Journal of Nutrition, 2011;106(10):1535-1543. DOI
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- Kenefick RW, Cheuvront SN. Hydration for recreational sport and physical activity. Nutrition Reviews, 2012;70 Suppl 2:S137-S142. DOI
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- Polhuis KCMM, Wijnen AHC, Sierksma A, et al. The diuretic effect of weak and strong alcoholic beverages in elderly men: a randomized crossover trial with controlled diet. Nutrients, 2017;9(7):660. DOI
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- Hooper L, Bunn DK, Downing A, et al. Which frail elderly persons are dehydrated? The DRIE study in the United Kingdom. The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences, 2016;71(10):1341-1347. DOI
- El-Sharkawy AM, Devonald MAJ, Humes DJ, et al. Hyperosmolar dehydration: a predictive factor for acute kidney injury and outcomes in hospitalized elderly persons. Clinical Nutrition, 2020;39(8):2593-2599. DOI
- Bunn D, Jimoh F, Wilsher SH, Hooper L. Increasing fluid intake and reducing dehydration risk in elderly persons in long-term care facilities: a systematic review. Journal of the American Medical Directors Association, 2015;16(2):101-113. DOI
- Steiner MJ, DeWalt DA, Byerley JS. Is this child dehydrated? JAMA, 2004;291(22):2746-2754. DOI
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- Guarino A, Ashkenazi S, Gendrel D, et al. Evidence-based recommendations from [two European pediatric learned societies] for the management of acute gastroenteritis in children in Europe: 2014 update. Journal of Pediatric Gastroenterology and Nutrition, 2014;59(1):132-152. DOI
- Hartling L, Bellemare S, Wiebe N, et al. Oral versus intravenous rehydration for treating dehydration due to gastroenteritis in children. The Cochrane Database of Systematic Reviews, 2006;2006(3):CD004390. DOI
- Hahn S, Kim Y, Garner P. Reduced osmolarity oral rehydration solution for treating dehydration due to diarrhea in children: a systematic review. BMJ, 2001;323(7304):81-85. DOI
- Freedman SB, Willan AR, Boutis K, Schuh S. Effect of diluted apple juice and preferred beverages compared to an electrolyte solution on treatment failure in children with mild gastroenteritis: a randomized clinical trial. JAMA, 2016;315(18):1966-1974. DOI
- Shirreffs SM, Taylor AJ, Leiper JB, Maughan RJ. Rehydration after exercise in man: effects of volume consumed and sodium content of the beverage. Medicine and Science in Sports and Exercise, 1996;28(10):1260-1271. DOI
- Maughan RJ, Leiper JB. Sodium intake and rehydration after exercise in man. European Journal of Applied Physiology and Occupational Physiology, 1995;71(4):311-319. DOI
- Maughan RJ, Leiper JB, Shirreffs SM. Restoration of fluid balance after exercise-induced dehydration: effects of food and fluid intake. European Journal of Applied Physiology and Occupational Physiology, 1996;73(3-4):317-325. DOI
- Shirreffs SM, Watson P, Maughan RJ. Milk as an effective post-exercise rehydration drink. The British Journal of Nutrition, 2007;98(1):173-180. DOI
- Maughan RJ, Watson P, Cordery PA, et al. Randomized trial evaluating the effect of different beverages on hydration status: development of a beverage hydration index. The American Journal of Clinical Nutrition, 2016;103(3):717-723. DOI
- Binder HJ, Brown I, Ramakrishna BS, Young GP. Oral rehydration in the second decade of the twenty-first century. Current Gastroenterology Reports, 2014;16(3):376. DOI
- Valtin H. "Drink at least eight glasses of water per day." Really? Is there scientific evidence for the "8 x 8"? American Journal of Physiology. Regulatory, Integrative and Comparative Physiology, 2002;283(5):R993-R1004. DOI
- Clark WF, Sontrop JM, Huang SH, et al. Effect of coaching to increase water intake on decline in kidney function in adults with chronic kidney disease: the CKD WIT randomized clinical trial. JAMA, 2018;319(18):1870-1879. DOI
- Spigt M, Weerkamp N, Troost J, et al. Randomized trial on the effects of regular water consumption in patients with recurrent headaches. Family Practice, 2012;29(4):370-375. DOI
- Almond CS, Shin AY, Fortescue EB, et al. Hyponatremia in runners of a [major American urban marathon]. The New England Journal of Medicine, 2005;352(15):1550-1556. DOI
