Difference Between Milk Allergy and Lactose Intolerance

Main Difference – Milk Allergy vs Lactose Intolerance

Milk allergy and lactose intolerance are two medical conditions we often come across when it comes to paediatrics. The main difference between milk allergy and lactose intolerance is that milk allergy is a true food allergy and indicate allergic symptoms whereas lactose intolerance is a condition which develops due to the absence of the enzyme Lactase in the body.

1. What is Milk Allergy?
     – Cause, Symptoms, Diagnosis, Tests, Prevention

2. What is Lactose Intolerance?
     – Cause, Symptoms, Diagnosis, Tests, Prevention

3. Difference Between Milk Allergy and Lactose Intolerance

Difference Between Milk Allergy and Lactose Intolerance - Comparison Summary

What is Milk Allergy

Milk allergy is a true immune reaction of the body against a protein present in milk (especially towards cow’s milk, but some patients might show this reaction against other milk types including Soy). Milk allergy usually develops early in life and affects infants and children under 3 years of age and accounts for the commonest type of food allergy seen in children (2%).It  is a known fact that most of these affected children will outgrow this allergic condition by the age of around 5.

Typical allergic reactions will start showing few minutes after the ingestion of milk, but in some children, this can be delayed up to several hours. Therefore, once the parents get to know that their child is having this sort of an allergic condition, it is important to be watchful after introducing any kind of milk product for the first time.

Symptoms of Milk Allergy

Commonest symptoms of milk allergy are,

  • Stomachache
  • Nausea and vomiting
  • Diarrhea
  • Skin rash
  • Difficulty in breathing
  • Swollen lips, tongue and throat

If any of these features are noted in your child, following milk or some dairy product ingestion, it is highly advisable to seek immediate medical advice. After the initial management of the allergy, your doctor will carry out a food allergy test by a skin prick or blood sample testing to confirm the presence of milk allergy.

There is no special treatment for milk allergy except for the normal management of allergic reactions depending on its severity. Milk allergies are rarely fatal or life-threatening, but it is always better to avoid dairy products or at least limit them up to a certain extent while consuming enough amounts of calcium.

Furthermore, always make sure to read food labels to check the content of the food; contents such as casein, lactulose, whey, lactalbumin and ghee should be avoided as much as possible.Difference Between Milk Allergy and Lactose Intolerance

What is Lactose Intolerance

This is a medical condition which occurs due to the absence or limited presence of the enzyme Lactase in the body, which is necessary to digest (break down) lactose sugar in milk and milk products.

Lactose intolerance can be a result of a genetic condition or damage to the intestines due to a bacterial or viral infection. It is more common than milk allergy and can develop at any age of life, particularly affecting the elderly age group.

Symptoms of Lactose Intolerance

Signs and symptoms of this condition can develop between 30 minutes to 2 hours following the ingestion of dairy products and include:

  • Stomach pain
  • Bloated feeling in the abdomen
  • Nausea
  • Diarrhea

How to Diagnose Lactose Intolerance

If a person experiences any of the above signs and symptoms and has a similar history following a dairy product ingestion, it is important to seek medical advice to avoid further occurrences.

Your doctor will carry out few tests to confirm the presence of this condition.

Test for Lactose Intolerance

  • Hydrogen breath test- partially or completely undigested lactose will result in high concentrations of hydrogen gas in your exhaling air. Doctors will measure this gas following the ingestion of a lactose-loaded beverage and confirm the condition.
  • Stool acidity test – Undigested lactose has a tendency to increase the acidity of stools. This method is usually used to confirm lactose intolerance in children.

Prevention of Lactose Intolerance

Measures taken to prevent lactose intolerance include,

  • Limitation of dairy products as much as possible.
  • Reassurance of the intake of nutrients which might get deprived with the limitation of milk and other dairy products e.g. Calcium
  • Consumption of lots of dairy free products like green leaves, leafy vegetables, fruits,
  • Seeking advice from a dietician
    Main Difference - Milk Allergy vs Lactose Intolerance

    Milk products like cheese, butter, cream, etc. can also cause lactose intolerance.

Difference Between Milk Allergy and Lactose Intolerance


Milk allergy is a true food allergy which develops against a protein contained in milk.

Lactose intolerance is a condition which develops due to the absence of the enzyme Lactase in the body.

Age Group

Milk allergy is commonly seen in infants and children below 3 years of age.

The incidence of Lactose intolerance is known to be increased with advanced age.


Lactose intolerance is a result of a bacterial or viral infection damaging the intestines or due to a genetic predisposition.

Milk allergy is solely an immune reaction.

Signs and Symptoms

Both these conditions cause gastric disturbances such as abdominal pain, nausea and vomiting, but milk allergy also has cause symptoms of a normal allergic condition including skin rashes and swollen lips and throat.

Image Courtesy: 

“Cheese Platter” (CC BY-SA 3.0) via Picserver.org

“435295” (Public Domain) via Pixabay

About the Author: Embogama

Embogama is a passionate freelance writer for several years. Her areas of interest include general medicine, clinical medicine, health and fitness, Ayurveda medicine, psychology, counseling and piano music