- Intolerance or allergy?
- What is lactose intolerance?
- Symptoms of lactose intolerance
- What cannot be eaten if you are lactose intolerant?
- How much lactose is in dairy products?
- What is a milk allergy?
- Symptoms of milk allergies
- What can not be eaten if you are allergic to milk?
- What's differentlactose intolerance from milk allergies - summary
VERIFIED CONTENTAuthor: Aleksandra Żyłowska-Mharrab, dietitian, food technologist, educator
Lactose intolerance most often affects adults, and milk allergy - children. Usually, in classic forms, it is no problem to distinguish them from each other. What exactly are both types of milk hypersensitivity? What are the symptoms of milk allergy and what are lactose intolerance symptoms? What should be excluded from the diet in the case of lactose intolerance, and what in the case of a milk allergy?
Intolerance or allergy?
Before we get into milk allergy and lactose intolerance considerations, it's helpful to understand where the difference lies between intolerance and allergy. Both food allergy and food intolerance cause an adverse reaction in the body after food consumption. However, this reaction takes place with the use of completely different mechanisms, its background is different.
Food allergy is a type of hypersensitivity that occurs when the immune system reacts inappropriately to food ingredients (most often proteins) and starts treating them like an intruder, activating the immune system. Common food allergies are usually IgE-mediated reactions.
Food intolerance causes an adverse reaction of the body without the involvement of the immune system. The mechanisms of intolerance can be different, often complex and difficult to recognize.
The causes of intolerance include :
- enzymatic factors,
- metabolic,
- pharmacological,
- toxicological
- and the mechanisms of idiosyncrasy, i.e. a variable reaction to the same factors typical only for a given person.
Intolerance and allergy can produce similar symptoms, although they are triggered by different mechanisms. This makes it difficult to diagnose the type of food hypersensitivity. However, in the case of milk allergy (the most common allergy among children) and lactose intolerance (the most common intolerance among adults), you can distinguish them from each other with a little scrutiny. Often their symptoms differ from each other.
What is lactose intolerance?
Lactose intolerance is one of the most common non-allergic food hypersensitivity reactions. It occurs mainly in adults and affects approx. 37% of Poles. Interestingly, the further north of Europe, the morelactose intolerance is more common. It hardly affects the southern nations - Italians or Spaniards.
Lactose intolerance occurs after the consumption of milk and dairy products, which are the source of milk sugar - lactose. The cause of lactose intolerance is the deficiency of the enzyme lactase, whose role is to digest lactose.
Lactase is produced in the epithelium of the small intestine and its amount naturally decreases with age. This is due to the fact that the basic human food at birth is mother's milk. In the early years of life, lactase activity is greatest. Over the years, when milk should be less and less part of the human diet, the body produces less lactase.
Lactose deficiency can occur as:
- alactasia- congenital lactose deficiency, a very rare form that occurs from birth, with symptoms including diarrhea shortly after consuming even a small amount of breast milk.
- adult hypolactasia- primary lactase deficiency that progresses naturally with age.
- secondary lactase deficiency- occurs as a result of lesions leading to damage to the epithelium of the small intestine, e.g. Crohn's disease, celiac disease, or parasitic infections.
Symptoms of lactose intolerance
The symptoms of lactose intolerance occur when the body cannot cope with digesting and absorbing milk sugar. Undigested lactose enters the large intestine, where it is fermented by the intestinal bacteria.
The severity of symptoms depends on the amount of lactose ingested and the level of lactase enzyme deficiency. Importantly, the symptoms do not appear immediately after eating yogurt or drinking coffee with milk, but from a few to several hours later.
Symptoms of lactose intolerance include:
- flatulence,
- diarrhea,
- constipation,
- stomach pains,
- feeling of splashing in the intestines,
- gas discharge,
- colic in babies.
What cannot be eaten if you are lactose intolerant?
If you are lactose intolerant, avoid dairy products that contain lactose, as well as all milk-based foods and drinks, e.g. cheesecakes, milk coffees.
Some people do not have to exclude them completely. Everyone has a different level of intolerance, which is why some people develop lactose intolerance symptoms from a slice of cottage cheese, and in others only a few glasses of milk.
The number of dairy products that do not cause ailments must be adjusted individually to each other. Currently, there are also solutions that allow almost completelyto get rid of the problem of lactose intolerance. You can take the lactase enzyme tablet with a dairy meal to replace the deficiency of the enzyme produced by the small intestine.
The stores also offer a very wide selection of lactose-free dairy products - from milk, through cottage cheese to butter and cheese.
Lactose-free milk tastes sweeter not because of the added sugar, but because the lactose in it is already broken down into glucose and galactose, and the glucose is sweet.
How much lactose is in dairy products?
| Lactose content in food products [g / 100g] | |
| Sweet cow's milk | 4.6 - 4.9 |
| Sweet goat's milk | 4,4 |
| Sweet sheep's milk | 5,1 |
| Cow milk powder | 39 - 51 |
| Condensed cow's milk | 9.4 - 10.3 |
| Yogurt | 4.6 - 5.0 |
| Kefir | 4,1 |
| Buttermilk | 4.7 |
| Whey | 5,1 |
| Yellow cheeses | 0,1 |
| White cheeses | 2.9 - 3.1 |
| "Feta" cheeses | 1.0 |
| Homogenized cheese | 2.0 - 2.9 |
| Cottage cheese | 3,3 |
| Processed cheese | 1.0 |
| Ice cream | 4,4 |
| Sour cream | 3.1 - 4.0 |
What is a milk allergy?
Milk allergy, or more precisely milk protein allergy, is an unwanted reaction of the immune system after the consumption of milk and dairy products.
The proteins that are mainly responsible for causing an adverse allergic reaction are:
- α-lactalbumin,
- β-lactoglobulin,
- bovine serum albumin,
- bovine immunoglobulins,
- casein allergens
- and bovine lactoferrin.
Cow's milk has a protein composition similar to that of other mammals, so often an allergic reaction appears after consuming any type of animal milk, not just cow's milk.
Allergy to milk occurs primarily in infants and children. It is estimated to affect 3-4% of children under the age of two and less than 1% of 10-year-olds. Milk allergy usually goes away on its own with age.
Milk allergy can come in three forms:
- immediate- completely dependent on IgE antibodies, where up to 45 minutes fromsymptoms such as vomiting, hives and even anaphylactic shock occur when consuming milk.
- intermediate- only partially dependent on IgE antibodies, symptoms appearing within 45 minutes to 20 hours after milk consumption and include vomiting, diarrhea and skin changes.
- delayed- independent of IgE antibodies, where various symptoms appear more than 20 hours after milk consumption.
Symptoms of milk allergies
An allergy to milk and dairy products usually causes symptoms other than lactose intolerance. Symptoms that appear after consuming milk include:
- anaphylactic shock (from a few minutes to 2 hours after consumption),
- hives,
- angioedema,
- itchy skin,
- atopic dermatitis,
- vomiting,
- diarrhea,
- colic,
- blood in stool,
- lack of appetite,
- Qatar,
- cough,
- difficulty breathing,
- anemia,
- anxiety,
- asthma.
Hypersensitivity to cow's milk (IgE-independent reaction) may manifest as dietary protein-induced colitis with repeated symptoms such as:
- vomiting,
- pallor,
- weakness and fatigue,
- as allergic inflammation of the rectum and colon,
- or allergic eosinophilic esophagitis that resembles reflux.
Symptoms of a milk allergy appear for the first time when introducing milk replacers to a child's diet, usually around the age of 6 months.
What can not be eaten if you are allergic to milk?
In the case of an IgE-dependent milk allergy, it is harmful to eat all amounts of milk and dairy products, which are the source of allergenic proteins. With the IgE-independent reaction you do not have to worry about trace amounts of milk and milk proteins.
The following should be excluded from the diet in case of milk allergy:
- milk, yoghurt, kefir, buttermilk, cottage cheese, yellow, white, melted, homogenized, blue cheese, mozzarella, feta,
- ice cream,
- milk porridges,
- formula milk,
- pudding,
- protein supplements,
- any baked goods with milk - cakes, cookies, biscuits, butter rolls, pancakes etc.,
- chocolate, chocolate bars,
- coffee with milk, cocoa, smoothies with milk or yoghurt or with the addition of protein supplement, hot chocolate,
- in the case of IgE-dependent allergy - all food products with the information "may contain allergens: milk, milk proteins".
What's differentlactose intolerance from milk allergies - summary
| Lactose intolerance | Milk allergy |
| Mainly found among adults. | Mainly found among infants and young children. |
| Increases with age. | It disappears spontaneously with age. |
| The symptoms relate to digestive tract ailments. | Symptoms include vomiting, skin changes, and respiratory problems. |
| The symptoms worsen with the amount of dairy products consumed. | Symptoms occur after consuming very little milk. |
| Symptoms of intolerance appear several to several hours after consuming dairy products. | Symptoms of IgE-dependent allergy occur within several to several minutes after consuming dairy products. |
| The cause of the body's reaction is the presence of milk sugar - lactose. | The reason for the body's reaction is the presence of milk proteins. |
| Lactose-free dairy products are safe to consume. | Do not eat any dairy or milk products, even in small amounts. |