Metabolic waterrefers towatercreated inside a livingorganismthroughmetabolism,byoxidizingenergy-containing substances in food and adipose tissue. Animal metabolism produces about 107–110 grams of water per 100 grams offat,[1]41–42 grams of water per 100 g ofprotein,and 60 grams of water per 100 g ofcarbohydrate.[2][1][3]
Some organisms, especiallyxerocoles— animals living in thedesert— rely exclusively on metabolic water. Migratorybirdsmust rely exclusively on metabolic water production while making non-stop flights, facilitated by the high metabolic rate during such flights.[4][5]Humans, by contrast, obtain only about 8–10% of their water needs through metabolic water production.[6]
Inmammals,the water produced from metabolism of protein roughly equals the amount needed to excrete theureawhich is a byproduct of the metabolism of protein.[6]Birds, however, excreteuric acidand can have a net gain of water from the metabolism of protein.
References
edit- ^abMellanby, Kenneth (July 1942)."Metabolic Water and Desiccation".Nature.150(3792): 21.Bibcode:1942Natur.150...21M.doi:10.1038/150021a0.S2CID4089414.
- ^Morrison, S. D. (1953-11-28)."A method for the calculation of metabolic water".The Journal of Physiology.122(2): 399–402.doi:10.1113/jphysiol.1953.sp005009.ISSN0022-3751.PMC1366125.PMID13118549.
- ^Medicine, Institute of; Board, Food Nutrition; Intakes, Standing Committee on the Scientific Evaluation of Dietary Reference; Water, Panel on Dietary Reference Intakes for Electrolytes and (2005).4 Water | Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate | The National Academies Press.p. 85.doi:10.17226/10925.ISBN978-0-309-09169-5.
- ^"Racing the wind. Water economy and energy expenditure in avian endurance flight".Archived fromthe originalon 2008-06-29.Retrieved2008-08-01.
- ^Klaassen M (1996)."Metabolic constraints on long-distance migration in birds".J Exp Biol.199(Pt 1): 57–64.doi:10.1242/jeb.199.1.57.PMID9317335.
- ^abBoard on Agriculture and Natural Resources (BANR),Nutrient Requirements of Nonhuman Primates: Second Revised Edition(2003), p. 144.[1]