Metabolic water
Metabolic water refers to water created inside a living organism through their metabolism, by oxidizing energy-containing substances in their food. Metabolism of fat produces about 110 grams of water per 100 grams,[1] protein 41.3 grams, and starch 55.1 g.[2]
Some organisms, especially xerocoles, animals living in the desert, rely exclusively on metabolic water. Migratory birds must rely exclusively on metabolic water production while making non-stop flights.[3][4] Humans, by contrast, obtain only about 8-10% of their water needs through metabolic water production.[5]
In mammals, the water produced from metabolism of protein roughly equals the amount needed to excrete the urea which is a byproduct of the metabolism of protein.[5] Birds, however, excrete uric acid and can have a net gain of water from the metabolism of protein.
[edit] References
- ^ http://www.nature.com/nature/journal/v150/n3792/abs/150021a0.html
- ^ http://www.encyclopedia.com/doc/1O39-metabolicwater.html
- ^ http://dissertations.ub.rug.nl/faculties/science/2005/s.b.engel/
- ^ Klaassen M (1996). "Metabolic constraints on long-distance migration in birds". J Exp Biol 199 (Pt 1): 57–64. PMID 9317335. http://jeb.biologists.org/cgi/pmidlookup?view=long&pmid=9317335.
- ^ a b Board on Agriculture and Natural Resources (BANR), Nutrient Requirements of Nonhuman Primates: Second Revised Edition (2003), p. 144. [1]
