Lactose, commonly known as “milk sugar”, may not be digested well if you are either born with absent or low levels of the enzyme lactase or if your intestine has been injured resulting in absent or low levels of lactase. Lactose is a disaccharide or two sugars linked. It is a combination of the two sugars, glucose and galactose. If intestines lack or are deficient in lactase you will not adequately digest lactose and you will experience gas, bloating, abdominal cramps and diarrhea shortly after eating something containing lactose.
The lactase enzyme is on the surface of the intestine cells where it is very vulnerable to intestinal injury. Some people are born with absent or low levels of lactase, therefore have congenital alactasia or hypolactasia. Between 80-100% of people of Asian, Native American, or African ancestry are lactose intolerant for this reason compared to only 15% of those of Northern European ancestry. (more…)