The Big Difference Between Lactose Intolerance And Dairy Allergies

You may have heard of lactose intolerance, as it's quite prevalent, especially in adults. According to MedlinePlus, about 65% of people are lactose intolerant. What you may not know is that lactose intolerance is distinct from a milk or dairy allergy.

According to Food Allergy Research and Education (FARE), milk is one of the eight major food allergies, along with eggs, wheat, fish, crustacean shellfish, peanuts, tree nuts, and soy. The American College of Allergy, Asthma, and Immunology (ACAAI) points out that between 2% and 3% of children under three are allergic to dairy. Experts used to think that these kids would outgrow this allergy when they hit age three, but one study suggested that as few as 20% will outgrow their milk allergy by the time they are four years old. That said, about 80% are likely to outgrow their milk allergy by the time they are 16 years old.

Lactose intolerance and milk allergy can sound similar, but the symptoms and ways they affect your body are quite different. So, how can you tell if you're lactose intolerant or allergic to dairy? There is one significant difference.

According to FARE, allergies trigger your immune system. If you're allergic to a certain food, your immune system reacts to its presence with symptoms that can range from mild to serious, including rashes, swelling, hives, difficulty breathing, wheezing, and fainting. Everyday Health adds that you can also experience stomach pain, diarrhea, and the swelling in your throat or lips. When severe, these symptoms can be fatal. 

In contrast, lactose intolerance does not involve the immune system (per FARE). If you're lactose intolerant, you're missing the enzyme lactase, which is needed to digest the sugar in cow's milk. When that sugar cannot be broken down, it may lead you to develop gas, cramps, bloating, nausea, and diarrhea. While this condition can be extremely uncomfortable, it's not life-threatening.  

Make an appointment with your doctor if you think you may be lactose intolerant or have a dairy allergy. Your doctor can do a hydrogen breath test or stool acidity test to determine if you're lactose intolerant (per Everyday Health). If they think you may have a dairy allergy, they'll refer you to an allergist who will perform a skin allergy test and possibly a blood test as well. If you have a milk allergy, you will need to limit or completely avoid consuming anything with milk in it, as well as ingredients such as ingredients such as ghee, casein, whey, lactalbumin, and lactulose. You may also need to carry an epinephrine injector in case of an allergic reaction (per FARE).