Lactose-Free vs Milk-Protein-Free: The Difference

Lactose-free food is not suitable for someone with cow's milk protein allergy (CMPA). A lactose-free product has had the lactose (milk sugar) removed or contains only a trace of it, but the milk proteins are still there. Lactose intolerance and CMPA are two different problems, and they differ both in their cause and in what you need to watch for when eating.

Two different problems

Lactose intolerance is a digestive problem. The body does not have enough of the enzyme lactase, which breaks down lactose, the sugar in milk. It shows up mainly as bloating, stomach pain and diarrhoea, and it often depends on how much you have eaten. The immune system does not usually play the main role.

Cow's milk protein allergy (often just called milk allergy) is an immune reaction to milk proteins such as casein or whey proteins. It can affect the skin, breathing or the digestive tract, and even a small amount may be enough. The difference between allergy and intolerance is explained in Allergy, intolerance and coeliac disease. Diagnosis is made by a doctor.

	Lactose intolerance	Milk protein allergy
What is the problem	milk sugar (lactose)	milk proteins
Mechanism	lack of the enzyme lactase	immune system reaction
Typical symptoms	bloating, stomach pain, diarrhoea	skin, breathing or digestive symptoms
Depends on the amount	often yes	even a small amount may be enough
Lactose-free product	may help	not suitable
Diagnosis	doctor	doctor / allergist

Why lactose-free cheese is not for someone with a milk allergy

Lactose-free milk, yoghurt and cheese are made by removing the lactose from a dairy product or breaking it down with the enzyme lactase. The proteins stay. That means:

• A lactose-free product still contains milk and is still a dairy product.
• With a milk allergy it is not suitable, because it contains what the person is allergic to.
• Hard cheeses naturally contain little lactose and may be easier to tolerate for someone with intolerance, but they do contain proteins.

In short: "lactose-free" is about the sugar, "milk-protein-free" is about the protein. They are not the same thing.

What about the allergen "milk (including lactose)"

The list of 14 EU allergens says "milk (including lactose)" (see the 14 EU allergens). The allergen label therefore covers milk as a whole, so even a lactose-free dairy product must show milk as an allergen. On Slovak menus this is usually number 7 (see Allergen numbers on menus).

If you see "lactose-free" on a menu, that is not proof that the dish is free of milk. For someone with an allergy, what matters is whether the dish contains milk.

Where milk hides

Milk proteins are not just in milk and cheese. They commonly turn up in:

• butter, cream, yoghurt, curd cheese,
• sauces and purées,
• bread, cakes and pastry,
• chocolate and sweets,
• breaded and fried food,
• some meat products and ready meals,
• whey and caseinate in the ingredients list.

In restaurant food, milk can also appear where you do not expect it, for example in a dressing, or as butter used to cook meat or vegetables. Ask about the method of preparation too, because a shared pan or utensils can carry traces.

What "dairy-free" and plant-based alternatives mean

Labels such as "dairy-free", "plant-based" or "vegan" do not always mean the same thing, and a restaurant may understand them in its own way. For an allergy it is not worth relying on a slogan. Ask specifically: "Does this contain milk or milk proteins, even in trace amounts?" "Vegan" is a useful indicator, but with CMPA it is not a guarantee, because cross-contamination from utensils or shared preparation is possible. More in Vegan restaurants and allergies.

Plant-based drinks (oat, soy, almond) and products made from them do not normally contain milk proteins, but they have allergens of their own: soy or nuts, and with oat products there is also a risk of gluten contamination. See also Soy allergy and Oats and coeliac disease. The difference between vegan and vegetarian food is covered in Vegan, vegetarian and flexitarian: the differences.

What to do in a restaurant

With lactose intolerance:

• Ask whether they have lactose-free alternatives (milk, cream, cheese).
• Find out whether the dish is free of milk or just contains less lactose.
• The amount you tolerate is individual. Your doctor can advise you.

With a milk protein allergy:

• Say "I have a milk allergy", not "I can't have lactose". For the kitchen these are different signals.
• Ask about preparation: butter in the pan, a shared pan, milk ingredients in the sauce.
• Lactose-free alternatives are not the answer.
• If the answer is not certain, choose another dish.

More about questions for the staff is in How to ask about allergens in a restaurant.

In AvoiDino you can set milk as your allergen and filter dishes. It is an aid for choosing, so always check the ingredients with the staff.

What labels in shops and on menus tell you

On packaged products, milk is highlighted in the ingredients list. On a restaurant menu you will find it under the allergen number or name. Words like "light", "fit" or "healthy" say nothing about milk. Look for the real ingredients list and, if necessary, ask. With a milk allergy, also avoid products with a "may contain traces of milk" warning unless your doctor has advised otherwise (see May contain traces).

Talk to your doctor

Some people with a milk allergy tolerate heat-treated dairy products and others do not. Decisions like this belong solely to a doctor or allergist. Do not test it yourself, and do not remove or reintroduce foods on your own. Children with a milk allergy should discuss their diet with a doctor, especially when it comes to substitutes.

Frequently asked questions

Is lactose-free cheese free of milk protein?

No. Lactose-free cheese has had the lactose removed or broken down, but it still contains milk proteins. It is not suitable for someone with a milk allergy.

Can someone with a milk allergy drink lactose-free milk?

No. Lactose-free milk still contains the milk proteins they are allergic to.

What is the difference between lactose intolerance and milk allergy?

Intolerance is a problem digesting milk sugar. Allergy is an immune system reaction to milk proteins.

Is hard cheese suitable with lactose intolerance?

Hard cheeses naturally contain little lactose and may be easier to tolerate. Tolerance is individual, however, and they are not suitable for an allergy.

How do I find out whether I have an allergy or an intolerance?

Only a doctor or allergist can tell the two apart. Do not start a diet on your own.

Sources

• Regulation (EU) No 1169/2011 of the European Parliament and of the Council on the provision of food information to consumers, Annex II (list of substances causing allergies or intolerances).

This information is general and does not replace medical advice. If you have an allergy, always check the ingredients with the staff.