Lactose Intolerance vs. Dairy Allergy

Lactose Intolerance vs. Dairy Allergy

There is often confusion between a lactose intolerance, the naturally occurring sugar in milk (from any mammal, including humans), and a milk allergy.

These two diagnoses and conditions are not interchangeable. 

Someone with a dairy allergy cannot have cheese, not even a small amount of parmesan cheese, as a topping on a salad.

However, someone with lactose intolerance most likely can have that without any consequences. 

So, let’s dive into the difference between lactose intolerance and a milk/dairy allergy. 

Cause: 

Lactose Intolerance: Gastrointestinal response from the inadequate ability to digest lactose (milk sugar)

Dairy Allergy: Immune system response to the protein found in dairy foods (whey and/or casein)

Severity: 

Lactose Intolerance: Causes temporary discomfort.

Dairy Allergy: Can be life-threatening (anaphylaxis)

Onset: 

Lactose Intolerance: Primarily affects adults but also affects children. 

Dairy Allergy: Primarily affects children, but also affects adults.

Symptoms: 

Lactose Intolerance: Diarrhea, nausea, abdominal cramping, bloating, fullness, gas. 

Dairy Allergy: (may include some of these symptoms or all of these symptoms) Diarrhea, vomiting, abdominal cramping; Angioedema, swelling of the deeper layers of the skin, caused by a build-up of fluid; Hives, red itchy skin; Stuffy or itchy nose; sneezing, or itchy, teary eyes

LACTOSE INTOLERANCE: 

Lactose-free milk is usually fine for
someone with lactose intolerance.

Lactose is a naturally occurring sugar in milk from any mammal, including humans.

Lactase is the enzyme in our body that helps break down and digest this sugar. If we don’t have enough of this enzyme, we may have difficulty digesting lactose.  

We can obtain the enzyme as a supplement “pill” before eating dairy products. Some food products have lactase added to them, including “lactose-free” labeled items. 

The level of intolerance can vary widely.  

Those with lactose intolerance can often tolerate the following: 

• Lactose-free milk

• Small amounts of “regular” milk (varies from ¼ cup to ½ cup)

• Yogurt since the naturally occurring bacteria in yogurt “digests” the lactose.

• Small amounts of cheese, cheddar, Colby, Monterey Jack, mozzarella, and Swiss, are naturally low in lactose per serving. 

But they may not be able to tolerate:

• A full 1 cup serving of “regular” milk.

• Cheese sauces such as on nachos or fondue

• Soft cheese, like cream cheese 

• Ice cream and milkshakes

• Custards

• Butter

Even a small amount of cheese or cream is an issue for someone with a dairy allergy.

DAIRY ALLERGY: 

An allergy is related to the PROTEIN in dairy foods. 

Someone with a dairy allergy cannot have any food containing whey or casein, the two proteins in milk.

Foods with whey and casein proteins include all forms of dairy, including butter, cheese, ice cream, yogurt, and any dairy-based product, including supplements such as Ensure for nutritional support and protein supplements that contain whey or casein, even if listed as “lactose-free.” 

Milk is one of the nine foods required for declaration on a food label.

The name of the food source of a major food allergen must appear in parentheses following the name of the ingredient immediately after or next to the list of ingredients in a “contains” statement. 

It would look like this on the food label, under the ingredients list: Contains: Milk.

Note: Lactose intolerance and dairy allergies require a medical test for accurate diagnosis, though avoiding them without a medical test is fine. 

If you can tolerate yogurt and some cheeses but not milk, it is NOT an allergy but more likely an intolerance.

However, if you claim you have a dairy allergy when you have lactose intolerance may contribute to confusion if you are okay with having cheese on your food.

---