Background of Lactose Intolerance

Lactose Intolerance
The history and origin of lactose intolerance current isn’t quite clear to scientists. However, studies have shown that some kind of genetic mutation did occur that caused the formation of lactose intolerance. It is most notably found in Asian people, with 90-98% of citizens living in Asia having some form of lactose intolerance, depending on which country you live in. 90-100% of Asian Americans, however are found to be lactose intolerant.
Lactose intolerance occurs in the human body when the cells that line the small intestine fail to make a required amount of enzymes known as lactase. The purpose of lactase in your body is to break down milk into simpler forms of sugar known as glucose and galactose, which are then absorbed into the bloodstream (much like how the pancreas works).
It is hard to tell if you actually have lactose intolerance though, because most people without common knowledge of lactose intolerance link the symptoms with cow’s milk. Lactose intolerance and cow’s milk intolerance are two totally separate things. Lactose intolerance is the inability to digest lactose due to a lack of lactase in the small intestine. This is primarily in the digestive system, where cow’s milk intolerance is an allergic reaction to the milk itself found in one’s immune system.
Also, to test if you do have lactose intolerance, you can take a lactose test or a hydrogen breath test. In the lactose test, it requires you to fast (no eating) before drinking some liquid that contains lactose. Then, over a 2 hour period of blood tests doctors check for an increase in the amount of glucose in your body. If you are negative for lactose intolerance the small intestine will break down the lactose into glucose or galactose and pass it on to the liver, which will make glucose to enter your bloodstream, raising the level in your blood. If you are positive, there will be no signs of a raise of glucose in your blood. The hydrogen test requires you to drink a glass of some liquid with lactose. Undigested lactose contains various gases, including hydrogen. Your breath normally contains very little hydrogen, so if there is an increase in the level of hydrogen when you exhale, you are positive for lactose intolerance.
There are currently 3 forms of lactose intolerance. The first is primary lactose intolerance, which is a condition that develops over time, usually due to weaning in a non-dairy society. This is found in many Asian and African cultures. The second form is secondary lactose intolerance, and is usually caused when there is damage done to the small intestine caused by certain gastrointestinal diseases. The third and final form is called congenital lactase deficiency, which is a genetic disorder found at birth and usually is diagnosed in early infancy. This disorder prevents the cells from making a sufficient amount of lactase.