Food Allergy

Is Being Lactose Intolerant The Same As Having A Dairy Allergy?

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Trust20 Contributors • 9 minute read

People have used the terms “allergy” and “intolerance” interchangeably for a long time. Today we’re breaking down the answer to a common question: is being lactose intolerant the same as having a dairy allergy?

The short answer: no.

Let’s look at why:

Is Being Lactose Intolerant the Same as Having a Dairy Allergy?

So, What About Whey?

How Can Foodservice Professionals Best Care for Customers with Dairy Allergies or Lactose Intolerance?

Is Being Lactose Intolerant the Same as Having a Dairy Allergy?

The long answer? Still no, because food allergies, intolerances, and preferences have biological differences and, therefore, result in different types of reactions in different people. 

Simply put, a dairy allergy (sometimes called a milk allergy) causes an immune system reaction, whereas an intolerance does not. 

Milk (and dairy in general) is one of the nine major allergens that currently have specific labeling requirements under the U.S. Food Allergen Labeling and Consumer Protection Act of 2004–and with good reason.1 A dairy allergy is one of the most common allergies, particularly in young children.

According to WebMD, as many as two in every 100 children under four years old are allergic to milk.2 On top of that, Akash Goel, MD, an assistant professor of medicine in the gastroenterology and hepatology division at Weill Cornell, says approximately 60-70% of the general population is lactose intolerant3 (and that number is actually over 80% in some parts of the world).

Lactose Intolerance

Dairy Allergy

Occurs when someone is missing the enzyme lactase that helps digest lactose, a sugar found in milk and dairy products.

Occurs when someone has an abnormal immune system response to milk, often cow’s milk, and related dairy products.

Causes digestive reactions that include, but are not limited to, bloating, gas, stomach cramps, nausea, vomiting, and diarrhea.

Causes immune reactions that include, but are not limited to: hives, wheezing, itching/tingling/swelling around the lips or mouth, stomach upset, vomiting, or anaphylaxis (a potentially life-threatening reaction that impairs breathing and can cause shock).

Onset of symptoms can occur 30 minutes to 2 hours after consuming milk or dairy products.

Onset of symptoms can occur immediately (within minutes to hours of exposure) or with a delayed response of 48 hours up to even a week after ingestion.

Most commonly found in adults and children over the age of 5.

Most commonly found in young babies and children under 5 years old.

People who are lactose intolerant can reduce symptoms by taking lactase enzyme supplements before eating dairy and buying lactose-free milk products.

People with a milk allergy should avoid dairy products at all costs. Repeated exposure will not necessarily reduce symptoms.

**Table sources: Cleveland Clinic4, ACAAI1, Nestle Health5, and AllergyRI6**

So, What About Whey?

Now, let’s talk about whey.

Whey is a protein found in milk. It contains only a small amount of protein, so it’s often more tolerable for people who are lactose intolerant (though not always). 

Some may assume that since it's only 20% milk protein, it must be safe for those with a dairy allergy or lactose intolerance.1

Unfortunately, that's not the case. Whey protein still contains milk protein, which can trigger an allergic reaction in those with a dairy allergy. For those with lactose intolerance, whey protein concentrate (which is a common ingredient in protein powders and bars) can still contain lactose and can trigger reactions in people with severe intolerance.

Again, it's important to note that not all whey products are created equal. Whey protein isolate, which goes through an extra filtration process to remove most of the lactose and fat, may be better tolerated by those with lactose intolerance. 

But again, for those with a dairy allergy, even whey protein isolate is not a safe choice.

How Can Foodservice Professionals Best Care for Customers with Dairy Allergies or Lactose Intolerance?

First things first: if a customer alerts you to their allergy or intolerance, take it seriously. It's not just a preference or a dietary choice–it could be life-threatening. Make sure you're taking every precaution possible to keep them safe. Although lactose intolerance often isn’t as dangerous as a dairy allergy, the reality is that it’s still quite unpleasant to deal with-and it shouldn’t be something your customers have to worry about.

With that in mind, here are a few other tips to help you care for customers with allergies or intolerances.

1. Swap Out Milk for Other Ingredients

Rice milk, soy milk, almond milk, oat milk, coconut milk-there are so many non-dairy options out there that can easily replace milk in recipes. Just be sure to check the ingredient list on your non-dairy milk of choice, as some brands may still contain traces of milk protein.

2. Check the Labels

Speaking of ingredient lists, checking the labels is absolutely crucial when it comes to accommodating customers with dairy allergies or lactose intolerance. Here are some key ingredients to watch out for:

  • Butter, butter fat, butter oil, butter acid, butter ester(s)

  • Buttermilk

  • Casein, casein hydrolysate, caseinates (in all forms), rennet casein

  • Cheese, including cottage cheese

  • Cream

  • Curds

  • Custard

  • Ghee

  • Half-and-half

  • Lactalbumin

  • Lactoferrin

  • Lactic acid starter culture, sour milk solids

  • Lactose and lactulose

  • Milk

  • Milk protein hydrolysate Pudding

  • Sour cream

  • Whey and whey protein hydrolysate

  • Yogurt

And here are some ingredients that often contain milk but are actually safe for those with dairy allergies or lactose intolerance:

  • Calcium lactate

  • Cocoa butter

  • Calcium stearoyl lactylate

  • Cream of tartar

  • Lactic acid (by itself - lactic acid starter culture may contain milk)

  • Sodium stearoyl lactylate

  • Oleoresin

  • Sodium lactate

When checking labels, look for any of the ingredients listed above. Keep in mind that some products may not list allergens on the label, so if you're unsure, ask the manufacturer or supplier directly.

Dairy and lactose can be found in all kinds of foods you might not think to look at, like baked goods, artificial butter flavoring, hotdogs, and sausages (which use the milk protein casein as a binder), margarine, nougat, bread, pasta, shellfish (often dipped in milk to reduce odors), tuna fish (casein), snack foods, and more.

Check and recheck everything, and be sure to retain food labels after the flood has been prepared in case there are any questions later on.

3. Rethink Kosher

Many people assume that kosher products are safe for those with dairy allergies, but this isn't always the case.7 A food product with a "D" or "dairy" following the circled K or U on a product label means the product contains or is contaminated with milk protein and should be avoided by those with a milk allergy. 

However, even products labeled "pareve" (meaning milk-free) may still contain small amounts of milk protein, so be cautious and don't assume that they're always safe.

4. “Dairy-Free” is Not a Regulated Term

Another thing to keep in mind is that "dairy-free" is not a regulated term. While "non-dairy" is regulated, it does allow some dairy in some cases, such as coffee creamers made from caseinate (a milk protein). 

So, just because something is labeled "dairy-free" or "non-dairy" doesn't necessarily mean it's safe for those with dairy allergies. Be sure to check the ingredients list carefully to avoid any hidden sources of dairy.

5. Avoid Cross-Contamination

This means making sure that any dishes or utensils that come into contact with dairy products are thoroughly cleaned before being used again. Consider maintaining separate cutting boards or prep areas for dairy products.

It's also important to keep dairy-free options separate from those that contain dairy. This may require a separate section in your kitchen and even separate storage containers. 

6. Educate Your Staff and Provide Constant Reminders

Make sure everyone knows which products contain dairy and which ones don't. Consider hanging up posters or providing training sessions to remind team members of the dos and don'ts. It can be easy to forget, especially during a busy shift, so these reminders can be extremely helpful.

7. Sheep and Goat Milk Might Not Be Good Substitutes

While they’re often marketed as alternatives for those who can't have cow's milk, the proteins in sheep and goat milk are actually very similar to cow's milk protein.8 This means that someone who is allergic to cow's milk may also be allergic to these alternatives. 

Because of this, it's important to provide a variety of non-dairy options, such as almond milk or soy milk, instead.

8. Keep the Dialogue Open With Your Customers

Encourage your customers to share any dietary restrictions they may have so that you can cater to their needs accordingly.

Make sure your menu is clearly labeled with dairy-free options, and be sure to communicate this information to the kitchen staff as well. It's also important for servers to ask customers about any dietary restrictions and to make sure that this information is passed on to the kitchen staff.

The Takeaway

While being lactose intolerant and having a milk allergy are not the same thing, the physical reactions to both are deeply unpleasant. Foodservice workers can protect themselves and the customers who dine with them by ensuring they understand where dairy shows up in their kitchens and by following best practices for preventing cross contact.

Knowing the difference between a food allergy and intolerance can help you better serve your customers- both those with and without dietary restrictions.

Having trouble making sense of it all? That’s where Trust20 comes in. With our unique products designed specifically for foodservice professionals, we’ll show you everything you need to know to accommodate customers with food allergies, intolerances, sensitivities, and more. 

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  1. American College of Allergy, Asthma, & Immunology: Milk Allergy | Causes, Symptoms & Treatment
  2. WebMD: Lactose Intolerance vs. Dairy Allergy
  3. Sharon Feiereisen: A Gastroenterologist and Allergist Share How To Tell if You Have a Dairy Sensitivity, Allergy, or Something Else
  4. Cleveland Clinic: Lactose Intolerance
  5. Nestle Health: Cow's Milk Protein Allergy Diagnosis and Management
  6. AAPRI Asthma & Allergy Physicians of Rhode Island: Dairy Allergy or Lactose Intolerance?
  7. Institute of Agriculture and Natural Resources Food Allergy Research and Resource Program: Dairy-Free and Non-Dairy?
  8. Australian Society of Clinical Immunology and Allergy: ASCIA Dietary Guide - Cow’s Milk Protein (Dairy) Allergy