Milk Intolerance


What are the symptoms of lactose intolerance?

If the enzyme lactase is deficient, or low, then the ability to absorb lactose will be greatly reduced causing symptoms such as bloating, flatulence, diarrhoea and abdominal pain.


What is lactose intolerance?

Lactose intolerance is the inability to absorb lactose - the predominant sugar in milk - into the digestive system. If lactose is not absorbed properly, it ferments and this results in abdominal pain, a bloated stomach, stomach rumbling, increased wind and diarrhoea. Lactose is a disaccharide, which means that it is composed of two other sugars bound together. In order for lactose to be absorbed, it must be split into those two smaller sugars by an enzyme called lactase, which is present in the lining of the small intestine. If the levels of the lactase enzyme are low or absent, then that splitting does not occur and fermentation of the lactose occurs by bacteria in the large intestine. Lactase activity is high in babies and declines as the amount of milk in the diet decreases. Some people may have very low lactase levels but not have any symptoms. The reason for this is unknown. A lactose tolerance test, a hydrogen breath test, or a stool acidity test is required for a clinical diagnosis.


What are the main proteins in milk?

The total protein component of milk is composed of numerous specific proteins. The primary group of milk proteins are the caseins. All other proteins found in milk are grouped together under the name of whey proteins. The major whey proteins in cow milk are beta-lactoglobulin and alpha-lactalbumin.


If cow’s milk comes up positive, does that mean that they are lactose intolerant?

No. Lactose intolerance is the inability to digest lactose, the major sugar found in milk. It is caused by a shortage of the enzyme lactase, which is produced by the cells that line the small intestine.