Precautions
Failure to maintain adequate water levels can lead
todehydration. While this may be the result of various
diseases, the initial symptoms are thirst and dry
mouth. followed by lightheadedness and dizziness
Although water intake is normally very safe,
excessive water intake, also known as hyperhydration,
can occur, and may be fatal. Excessive water intake
can lead to dilution of the sodium levels in the body,
causing hyponatremia. This condition is sometimes
seen in infants who may ingest too much water, either
because they are given only water to drink or because
excessive water is used to dilute infant formulas. Water
intoxication may also result from severe vomiting or
diarrhea in which the fluid is replaced with water,
without replacing theelectrolytes. Rarely, athletes
who have undergone very great extertion may perspire
excessively, and, if the fluid loss is replaced with water
without electrolytes, may experience water intoxica-
tion. Althoug this is very rare, it did occur at the 2007
London Marathon, when temperatures were unsea-
sonably warm that over 5,000 runners needed to be
treated on site. Over 70 runners were taken to the
hospital for treatment and one first-time marathoner,
22 years of age, died from hyperhydration. Voluntary
hyperhydration has been reported and has been
known to be fatal. On occasion, hyperhydration has
been reported as part of school hazings.
Symptoms of water intoxication are similar to
those of dehydration: muscle cramps, confusion, nau-
sea, slurred speech and disorientation. Because of this,
althletes may mistake water intoxication for dehydra-
tion, and drink even more water after toxicity has
appeared. The goal of rehydration is to drink just
enough water to replace the amount lost to perspira-
tion. Forcing fluids can be dangerous. While sports
drinks replace electrolytes, they may also provide a
high level of calories. For people exercising to lose
weight, an appropriate amount of water has been advo-
cated as the most appropriate method of rehydration.Complications
Weight loss programs should target body fat;
however, some weight-loss remedies, in an attempt to
show prompt results, have incorporated diuretic
drugs. These may lead to loss of body water, with the
risk of dehydration.Parental concerns
Adolescents and teen-agers should be aware of
the hazards associated with hyperhydration. Childrenof this age may be at risk both of excessive water
intake after athletics, and also as part of school hazing
rituals.Resources
BOOKSLide, David, editor.CRC Handbook of Chemistry and
Physics, 87th edition.Boca Raton, Florida: CRDC
Press, 2006.
PERIODICALS
Gray RW, French SJ, Robinson TM, Yeomans MR.
‘‘Increasing preload volume with water reduces rated
appetite but not food intake in healthy men even with
minimum delay between preload and test meal.’’Nutr
Neurosci.2003 Feb; 6(1): 29-37.
Keating JP, Schears GJ, Dodge PR. Oral water intoxication
in infants. An American epidemic.Am J Dis Child. 1991
Sep; 145(9): 985-90.
Norton GN, Anderson AS, Hetherington MM. ‘‘Volume
and variety: relative effects on food intake.’’Physiol
Behav.2006 Apr 15; 87(4): 714-22. Epub 2006 Mar 3.
Rolls BJ,Bell EA,Thorwart ML. ‘‘Water incorporated into a
food but not served with a food decreases energy intake
in lean women.’’Am J Clin Nutr.1999 Oct; 70(4):
448-55.
Stiefel D, Petzold A. ‘‘H 2 O Coma.’’Neurocrit Care.2007;
6(1): 67-71
ORGANIZATIONS
Baby Milk Action. 34 Trumpington Street, Cambridge, CB2
1QY UK. Phone: 01223 464420; +44 1223 464420
(outside UK).<http://www.babymilkaction.org>
Mothers Against School Hazing (MASH). PO Box 14121,
Baton Rouge, Louisiana 70898.<http://www.mashinc.
org>.
Urgent Care Association of America. 4320 Winfield Road,
Suite 200 Warrenville, IL 60555. Phone: (877) 698-2262.
<http://www.ucaoa.org>.Samuel D. Uretsky, PharmDWeight cycling
DefinitionWeight cycling is losing weight by dieting, regain-
ing that weight and possibly more within a few months
to a year, dieting and losing weight again, then putting
the weight back on. Weight cycling is also called yo-yo
dieting. It is the opposite of weight maintenance.Weight cycling