what is theLactose intolerance? The lactose intolerant person is not able to fully digest the sugar present in milk and its derivatives. Lactose intolerance can be of two types. Of genetic origin, and be present already in childhood or manifest in adulthood as a consequence of the progressive decrease in the production of the lactase enzyme, or it can be associated with other problems.
Problems affecting the intestine, such as celiac disease, intestinal infections, or drug therapies, such as chemotherapy. In the second case, after a suitable elimination period and after fixing the responsible cause, lactose intolerance can regress. In Italy it affects almost one in two people.
Why does it occur?
The lack of the lactase enzyme prevents the digestion of lactose, milk sugar and its derivatives in the small intestine. Not being absorbed, when the lactose reaches the colon and finds the bacterial flora, it is fermented producing gas, in particular hydrogen, thus generating the symptoms.
What are the symptoms?
In relation to the level of intolerance, the symptoms range from a slight sense of abdominal swelling to much more annoying symptoms. These can include abdominal pain, diarrhea or constipation, bloating, but frequently also general symptoms such as nausea, tiredness, headaches and skin problems. Symptoms subside with a lactose-free or low-lactose diet. Clearly the symptoms depend on the amount of lactose taken in the diet.
How can I know if I’m intolerant?
The most common diagnostic test to find out if you are lactose intolerant is the breath test. It consists of the analysis of the exhaled air before and after the intake of a certain amount of lactose. If lactose is not absorbed due to lack of lactase, there is an increase in gas, and in particular hydrogen. The level reached, as well as any symptoms that occur during or in the hours following the test, also give an idea of the seriousness of the problem and how strict the diet should be.
Dietary indications.
It is important to avoid or reduce the main sources of lactose. So milk, cream and fresh cheeses, both from cows and goats or other animals, and the derivatives that contain them, such as ice creams, bakery products, milk chocolate, etc. Fortunately, aged cheeses such as parmesan, grana, but also gorgonzola, contain small quantities of lactose and, apart from particularly serious cases, do not cause reactions in intolerant people. In the shops there are also many delactosed foods, i.e. lactose-free or low in lactose. Unfortunately, the sources of lactose are often masked and the main ones are present in packaged foods in the form of milk powder and whey powder. Powdered milk contains 10 times more lactose than normal milk, this would explain, at least in part, the significant increase in intestinal problems related to lactose intolerance. In case of lactose intake, to prevent symptoms, a lactase supplement can be associated with the meal, precisely the enzyme that is lacking in intolerant people.
Useful tips
- If the symptoms are relevant and persist after the elimination of lactose, evaluate possible allergies or intolerances to milk proteins.
- A healthy intestine is able to digest a certain amount of lactose; therefore, it is also important to have a healthy diet as a whole, which favors a good bacterial flora.
- Avoid excessive consumption of lactose-free foods, preferring foods that are naturally low in lactose.
- However, whole white yogurt can be a good food taken in small doses. It is often tolerated, as well as providing numerous and important lactic ferments.
Fabio Diana
Specialist in Internal Medicine and Sports Medicine
www.fabiodiana.it