Lactose intolerance arises when the small intestine does not produce enough of an enzyme (lactase) that allows it to digest milk sugar (lactose).

In general, lactase converts milk sugar into two simple sugars (glucose and galactose) that are absorbed through the intestinal mucosa and enter the bloodstream.

The signs and symptoms of lactose intolerance usually begin between 30 minutes and two hours after you have eaten or drunk lactose-containing foods. The following are common signs and symptoms:

• Diarrhea
• Nausea and, sometimes, vomiting
• Colic
• Swelling
• Gases

In some cases, also and paradoxically, constipation may appear, this is due to a decrease in bowel motility as a result of methane-producing bacteria. These symptoms are similar to other digestive diseases such as celiac disease, Crohn ‘s disease or intolerance to milk proteins by other mechanisms so that one must distinguish between them through relevant evidence, especially in the case to remove lactose from the diet and there is no improvement in symptoms.

Likewise, the  intensity of the symptoms of lactose intolerance will  not only depend on the threshold of each person, but also on the amount of lactose ingested, the type of milk that has been taken, the intestinal motility, the activity of lactose (responsible for metabolizing lactose), the ability of the colon to absorb water, consumption together with other foods and the activity of its flora.

To diagnose lactose intolerance in any of its forms, several methods are used, and the simplest is to eliminate lactose from the diet and evaluate if symptoms disappear.

• The test of lactose intolerance or plasma glucose is based on the increase in blood sugar levels greater than 20 mg / dL, after one hour of consuming a load of 50 g of lactose. If this increase does not occur, the test is positive, since it means that the disaccharide has not been hydrolyzed and absorbed.

• The acidity test in stools is used mostly in young children and infants, in which it is difficult to perform other tests. It consists of analyzing the depositions that, in the case of lactose malabsorption, are more acidic than normal, because when the lactose is metabolized by the bacterial flora of the large intestine, the lactic acid content in the stools increases.

Other diagnostic methods are intestinal biopsy to quantify enzymatic activity and genetic study .

It is common to confuse lactose intolerance with irritable bowel syndrome, so the differential diagnosis should be made to confirm that it is a lactase deficit and not another type of intestinal disorder. If you would like to know more, please log on to www.www.testyourintolerance.co and find out how we can help you to identify your sensitivities.