Lactose is a carbohydrate (sugars) found in milk, milk products, and other items.
For the body to digestion lactose it must be hydrolysed by the enzyme lactase which located on the tip of small intestine lining that contain tiny hair-like structures called villi.
Lactose intolerance occurs if these lactase enzyme levels are defective or if they decrease over time or they are damaged.
Symptoms of lactose intolerance include gas, bloating, nausea, abdominal cramping and diarrhoea. Symptoms may vary and they are similar to those who suffer from coeliac disease and therefore is recommended to see a physician to be correctly diagnosed.
There are three different types of lactose intolerance including primary, acquired (or secondary), and congenital.
Primary lactose intolerance is genetic and is usually tolerated during infancy and childhood. However as you increasing age the ability to produce lactase decreases leading to lactose intolerance.
People who suffer with coeliac disease may have primary lactose intolerance, however acquired or secondary lactose intolerance seems to be more common.
Acquired lactose intolerance is the consequence of a decrease or deficiency of lactase due to damage of villi located in the small intestine. The villi damage linked to coeliac disease is frequently caused by an inflammatory immune-response to the consumption of gluten or it may also be the result of illness, injury, surgery or even excessive gastro. Acquired lactose intolerance can also be temporary or permanent.
Children with coeliac disease are more likely to have temporary lactose intolerance as they tend to be diagnosed and treated sooner than adults which allows faster healing of the villi and the regeneration of lactase.
Congenital lactase deficiency is rare and not associated with coeliac disease.
The cause of congenital lactase deficiency is a mutation in the gene responsible for making lactase. Infants with congenital lactase deficiency cannot tolerate lactose containing formulas or breast milk and are fed a lactose-free formula and therefore need to be on a strict lactose free diet for life.
Lactose intolerance can be diagnosed in two ways. One is a breath hydrogen test and the other is a stool acidity test. The stool acidity test is more commonly used for infants and young children and older children and adults the breath hydrogen test can indicate lactose malabsorption.
Some foods, medications as well as smoking can interfere with the accuracy of breath hydrogen test, so it is recommended before having the test check with a medical professional.
Treatment for lactose intolerance depends on lactase activity and can be influenced by when and how much is consumed. Having small amounts of lactose several times a day is better tolerated than the consumption of large amounts at one time. Other ways to improve your tolerance to lactose is to use oral lactase enzymes and to consume milk treated with Lactaid which is a natural enzyme that helps break down lactose or dairy with acidophilus which is a bacteria culture.
The nutrient content of milk substitutes is not the same as breast or cow’s milk so they do not have adequate calcium and are not appropriate for infants and smaller children. For adults who take milk substitutes should take a daily calcium and vitamin D supplement.
Lactose can also be found in many medications and in all types of food so you should read labels to see if they contains lactose or for ingredients such as milk solids, whole or skim milk powder and whey; because lots of non-dairy products made from milk derivatives will contain lactose.
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