The difference between lactose allergy and lactose intolerance
Milk is a product with a double reputation. On the one hand, it is a source of important proteins and useful trace elements, on the other hand, it is a common cause of adverse reactions.
In particular, milk and milk products can cause allergies and intolerances. These two conditions, which are quite often confused with each other and considered related, in fact have a completely different nature.
Lactose intolerance is characterized by the inability of the body to fully digest milk sugar, which is called lactose. This condition can develop, primarily due to a deficiency in the body of a special enzyme – lactase .
Lactase breaks down lactose into two simple sugars – glucose and galactose, which are then easily absorbed into the blood.
During infancy, lactase is produced in the human body mainly so that babies can digest breast milk.
That is why most babies have enough lactase levels to digest almost a liter of breast milk per day. The enzyme lactase is naturally produced by the cells that line the small intestine. It is also produced by bacteria that live in the small intestine.
However, over time, about 70% of the world’s population stops producing this enzyme. This occurs around the age of 2-3 years. Therefore, later the human body can digest only a very small amount of milk and dairy products. And this is considered normal.
Lactose intolerance is more common in certain ethnic groups, including American Indians, African Americans, and Asians.
Most often, this condition affects the population of Africa (65-75% of the total population) and Asia, where more than 90% of the inhabitants are lactose intolerant.
In Northern and Central Europe this problem is less common. Here, lactose intolerance occurs in 2-20% of the population, depending on the region. Thus, in Mediterranean countries, lactose intolerance can reach an average of 40%. In particular, in some regions of Italy, this figure can reach 56-70%.
This difference is due to a genetic mutation, which, as scientists suggest, occurred 5-10 thousand years ago.
The ability to digest lactose gave people with the mutation a selective advantage in consuming dairy products. This allowed them to live long enough to have children. At the same time, the ability to digest lactose can be genetically transmitted to the next generations.
Babies are rarely diagnosed with lactose intolerance, but a viral infection or an immunization reaction can cause diarrhea when milk-based formula is taken. Since these secondary intolerances are usually short-lived, they often resolve on their own and do not require any dietary changes.
In contrast, in adults, lactose intolerance often manifests itself before the age of 20 years and requires some adjustment in nutrition.
In people with lactose intolerance, some of it remains in the intestines without being absorbed.
This undigested lactose passes into the large intestine. Here it is broken down by bacteria, causing bloating and, accordingly, flatulence. In addition, fermented lactose irritates the inner walls of the intestines, causing nausea, vomiting, and diarrhea. In addition, it is a source of toxins.
There is also an opinion in the scientific world that these toxins can cause the development of diabetes, multiple sclerosis, rheumatoid arthritis and some types of cancer.
The main symptoms of lactose intolerance include:
bloating and pain in the abdomen
Less commonly, lactose intolerance can lead to headaches, joint and muscle pain, lethargy, short-term memory problems, mouth ulcers, heart palpitations, depression, and more.
Typically, symptoms of lactose intolerance appear between 30 minutes and two hours after ingesting milk or dairy products.
DIAGNOSTICS OF LACTOSE INTOLERANCE
Lactose intolerance can be diagnosed with the following medical tests:
Stool acidity test
This test is often used to diagnose intolerance in infants and children. A stool sample is taken to determine if lactose is hydrolyzed to simple sugars. Fermentation of lactose in the intestines will produce lactic acid, which lowers the pH of the stool.
Hydrogen breath test
This is the most commonly used test in which the amount of hydrogen in a person’s breath is measured after drinking a drink containing lactose. An increase in hydrogen levels indicates that the body is not able to digest or metabolize lactose properly.
· Blood analysis
During this test, the patient is given a lactose-laden drink to drink, and then blood samples are taken every 2 hours to check their blood glucose levels. If the glucose level does not rise, it means that the person is lactose intolerant.
In the case of a confirmed diagnosis of lactose intolerance, treatment is mainly limited to lactose restriction. Most people can tolerate the small amount of lactose found in about 200 ml of milk (a small glass). Therefore, they are advised to minimize, but not completely limit, lactose in their diet.
Foods with the highest amount of lactose are milk, cream, ice cream and yogurt. Yoghurts with added cultures such as acidophilus have the most lactase activity , so they are easier to tolerate.
Different cheeses also contain different amounts of lactose. So, feta and cream cheeses contain more lactose, and ripened cheeses such as parmesan, cheddar or camembert contain almost no lactose.
A small amount of lactose is found in a large number of non-dairy products, as it is often used in the food industry. So, lactose can be added to bread, cereals and instant soups, to salad cream, mayonnaise, cookies, chocolate, chips, to some types of meat products (ham, sausages …).
Today there are special tablets containing the enzyme lactase . They help fight the symptoms of intolerance and digest lactose.
ALLERGY TO MILK
Unlike lactose intolerance, in the case of allergies, there are no particular racial or ethnic groups that show a greater prevalence of this reaction to milk.
Allergies to milk and products containing milk proteins are more likely to be acquired by people with eczema, allergies, or those whose parents suffered from allergies.
Allergies activate the immune system. Therefore, a person reacts to the proteins present in milk (primarily casein), perceiving them as hostile and releasing certain substances to protect against these imaginary enemies.
Proteins in milk bind to IgE antibodies produced by the human immune system after the first episode of an allergic reaction to milk. This binding triggers an immune response. It leads to symptoms that can be mild or very severe.
In this case, the body does not react to lactose. Therefore, individuals who are allergic to milk may take lactose if it separates from milk proteins, as occurs with some processed dairy products.
Also, unlike lactose intolerance, milk allergy usually appears early in life. This is the most common food allergy in children. It affects about 2.5% of children under 3 years of age. Among children of the first year of life, this figure, according to some data, can reach 7.5%. At the same time, many children can outgrow their milk allergy before the age of 5. But this does not mean that such an allergy cannot occur at any time in life, even in adulthood.
However, milk allergy in adults is rare. However, the severity of the reaction in them can be much stronger than in children. At the same time, even small portions of a dairy product can cause a reaction – up to 0.3 mg of cow’s milk protein.
Therefore, as a treatment and prevention for people with a milk allergy, it is recommended to avoid its consumption. After all, with prolonged exposure to an allergen, reactions to it can worsen, sometimes becoming life-threatening.
Milk allergy symptoms
Anaphylactic shock is a rare but severe type of allergic reaction. It can lead to breathing problems, a drop in blood pressure, and heart failure. Usually, anaphylaxis manifests itself as a systemic reaction – that is, one in which several organs are involved simultaneously.
Sometimes a milk allergy can lead to severe and unexpected symptoms such as swelling in the mouth or throat, wheezing, coughing, shortness of breath, and difficulty breathing.
But in most cases, the symptoms of an allergic reaction are:
itchy rash or swelling
· abdominal pain,
diarrhea or constipation
Newborns may have blood in the stool.
These symptoms may appear almost immediately or up to 72 hours after consumption of the dairy product.
DIAGNOSTICS AND TREATMENT OF MILK ALLERGY
To confirm the diagnosis of “allergy”, the doctor must carefully study the history of the disease. Sometimes a patient may be tested for lactose intolerance.
skin test may be performed to diagnose allergies . During this procedure, a small drop of liquid containing the milk allergen is applied to the skin. After that, the doctor looks to see if a characteristic reaction to the stimulus appears.
Also, the doctor may recommend doing a molecular allergy testto determine the amount of antibodies to cow’s milk proteins.
To confirm an allergic diagnosis, a provocative test can also be performed . That is, the doctor will let you try under control certain products that may contain milk and observe the reaction.
If you have a confirmed allergy to cow’s milk, your doctor may also recommend avoiding milk from other pets. This is because, for example, goat’s milk protein is similar to cow’s milk protein and can also cause a reaction in people who are allergic to milk.
When avoiding milk, you need to remember that it can be “hidden” in a number of seemingly dairy-free products. For example, in caramel, chocolate, sausages, and so on.
If you have a severe allergy or have ever had anaphylaxis before, talk to your doctor about getting an epinephrine autoinjector to help stop or slow down that severe allergic reaction if it happens again.
If you are limiting or avoiding milk, good sources of calcium and the vitamin A it contains include foods such as:
- leafy greens,
- dried beans,