Can lactose intolerance or milk allergy change over time?

Yes, both lactose intolerance and milk allergy can change over time, but in different ways and with varying probabilities, especially between children and adults. Understanding the differences between them is important to determine how each condition progresses.

Changes in Milk Allergy Over Time

Milk allergy is an immune response in which the body mistakenly identifies milk proteins as harmful, leading to symptoms ranging from mild to severe [1]. Milk allergy is more common in children compared to adults, and fortunately, most children outgrow their allergy to milk, eggs, soy, and wheat as they get older. However, allergies to peanuts, tree nuts, fish, and shellfish often persist into adulthood [1].

If a food allergy, including milk allergy, begins in adulthood, it is more likely to be lifelong [1]. There is no way to predict when allergic reactions might change from mild to severe, so it is important to determine if a person has a food allergy as soon as symptoms appear [1]. Allergy tests can help determine if an allergy has disappeared over time [1].

Changes in Lactose Intolerance Over Time

Lactose intolerance is a condition in which the body cannot fully digest the sugar lactose found in milk and dairy products, due to a lack of the lactase enzyme in the small intestine [2]. Unlike milk allergy, the immune system is not involved in lactose intolerance [1]. Symptoms are usually related to the digestive system and include bloating, diarrhea, gas, and nausea after consuming dairy products [3].

Generally, lactose intolerance is a chronic condition that tends to last a lifetime once it develops. However, the severity of symptoms may vary from person to person, and some people may be able to tolerate small amounts of lactose without symptoms [3]. In rare cases, lactose intolerance may be temporary, such as after certain gastrointestinal infections that damage the intestinal lining, but this is usually transient.

Key Differences and Their Impact on Prognosis

The main difference between allergy and intolerance lies in the response mechanism. Allergy involves the immune system and can be life-threatening in some cases (e.g., anaphylaxis), and can be triggered by even a very small amount of the offending food [1]. In contrast, lactose intolerance primarily affects the digestive system and is rarely life-threatening, and symptoms may only appear when consuming large amounts of lactose [1].

Due to these differences, the likelihood of 'recovery' or change in allergy is higher in children, as their immune systems can develop and adapt [1]. Lactose intolerance, on the other hand, is often the result of a lactase enzyme deficiency, which may be hereditary or develop with age, and does not tend to disappear spontaneously [3].

Next Steps and Medical Follow-up

If you suspect that you or your child suffers from a milk allergy or lactose intolerance, it is essential to consult a doctor or an allergist. A physician can determine the appropriate tests for an accurate diagnosis [1]. For example, blood or skin tests may be used to diagnose an allergy, while breath or stool tests are used to diagnose lactose intolerance [2].

In the case of milk allergy, the doctor may recommend completely avoiding milk and its products, and may prescribe an epinephrine autoinjector for emergency use in the event of a severe allergic reaction [1]. In the case of lactose intolerance, symptoms can be managed by reducing or avoiding foods that contain lactose, or by using over-the-counter lactase enzyme products [3]. It is also important to ensure you get adequate amounts of calcium and vitamin D from other sources if dairy products are excluded from the diet [2].

For more information on the differences between lactose intolerance and milk allergy and dietary alternatives, you can visit Lactose intolerance and milk allergy: Differences and dietary alternatives in Jordan (Arabic).

Medical references

• Food Allergy Testing
• Lactose Intolerance
• Lactose Intolerance