Difference between revisions of "Lactose intolerance"
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The proportion of lactose intolerant individuals varies by region on the planet. 99% of [[China|Chinese]] are lactose intolerant, whereas only 10% of [[United States|Americans]] are. Recent research indicates that lactose intolerance is high where [[cow]]s were not domesticated. <ref>http://evolution.berkeley.edu/evolibrary/news/070401_lactose</ref>At higher latitudes, lactose intolerance decreases. As average temperature increases, lactose intolerance increases.<ref>http://www.sciencedaily.com/releases/2005/06/050602012109.htm</ref> | The proportion of lactose intolerant individuals varies by region on the planet. 99% of [[China|Chinese]] are lactose intolerant, whereas only 10% of [[United States|Americans]] are. Recent research indicates that lactose intolerance is high where [[cow]]s were not domesticated. <ref>http://evolution.berkeley.edu/evolibrary/news/070401_lactose</ref>At higher latitudes, lactose intolerance decreases. As average temperature increases, lactose intolerance increases.<ref>http://www.sciencedaily.com/releases/2005/06/050602012109.htm</ref> | ||
| − | Lactose tolerance is determined by a [[recessive]] [[gene]]. Researchers have recently identified a [[DNA]] [[mutation]] that allows people to tolerate milk.<ref>http://www.foodnavigator.com/news/news-ng.asp?id=42796-scientists-identify-lactose</ref> | + | Lactose tolerance is determined by a [[recessive]] [[gene]]. Researchers have recently identified a [[DNA]] [[mutation]] that allows people to tolerate milk.<ref>http://www.foodnavigator.com/news/news-ng.asp?id=42796-scientists-identify-lactose</ref> Lactose tolerance is often called lactose persistence. |
==References== | ==References== | ||
Revision as of 20:14, April 26, 2007
Lactose intolerance is a condition wherein an individual cannot digest lactose, a sugar found in milk. When a lactose intolerant individual ingests any form of milk, he or she will get a stomachache. Other symptoms include cramps and bloating. Such individuals do not produce an enzyme called lactase that breaks down lactose after weaning.[1]
The proportion of lactose intolerant individuals varies by region on the planet. 99% of Chinese are lactose intolerant, whereas only 10% of Americans are. Recent research indicates that lactose intolerance is high where cows were not domesticated. [2]At higher latitudes, lactose intolerance decreases. As average temperature increases, lactose intolerance increases.[3]
Lactose tolerance is determined by a recessive gene. Researchers have recently identified a DNA mutation that allows people to tolerate milk.[4] Lactose tolerance is often called lactose persistence.
