Lactose intolerance often gets confused with a milk allergy, but they’re not the same thing … like, at all.
A milk allergy means you’re allergic to a milk protein, whereas lactose intolerance means you aren’t able to digest the sugar found in milk.
When someone with a milk allergy ingests a milk product, their immune system feels like it’s under attack, and releases antibodies that trigger an allergic reaction – which can range from hives and wheezing, right up to to vomiting, diarrhea, an asthma attack, or anaphylaxis.
Someone with lactose intolerance is not allergic to any part of the milk, but they’re unable to digest the sugar found in milk. If they eat or drink a product containing milk, they can be plagued with gastrointestinal issues, like stomachaches, diarrhea, gas.
Since stomachaches and diarrhea are potential side effects of either a milk allergy or intolerance, people get confused and think of them as the same condition.
We suspected our daughter, Charlotte, had a milk allergy around her first birthday, because she would have terrible stomach pain and diarrhea after ingesting milk or ice cream. But we had her tested, and she wasn’t allergic – just suspected to be lactose intolerant.
The trouble with lactose intolerance is that there isn’t a test for it – it’s just a matter of cutting milk out completely, and seeing if the symptoms improve. So we started giving her rice milk (fail), almond milk (fail), and ultimately lactose-free milk (win) – which is cow’s milk with the lactose (milk sugar) removed.
Charlotte can eat small amounts of hard cheese and yogurt without a problem, so it really hasn’t been a big deal (unlike her egg allergy). We keep her away from ice cream, whipped cream, cow’s milk, and anything else that’s straight-up lactose, basically.
If someone were to feed her ice cream, she wouldn’t be in any danger – other than, uh, needing to spend some serious time on the potty later on. But this experience has made me more cautious of the kids out there who do have actual milk allergies.
Despite the growing number of people with severe milk allergies, you still hear of people proclaiming they’re “allergic” to milk – when, really, they’re just lactose intolerant and don’t want to get the runs out in public. But the word “allergy” shouldn’t be thrown around. A child with a severe milk allergy couldn’t even come in contact with a milk product – like sidewalk chalk containing casein – without getting a reaction.
So just a reminder, that if you’re hosting a playdate or a party, always ask if anyone has an allergy or an intolerance. Never assume that “just a little” of something is probably fine, and never confuse a milk allergy with lactose intolerance.
Basically, it’s the difference between having a potentially fatal peanut allergy, and passing on the Peanut Butter Fudge Crunch ice cream so you’re not running to the bathroom at the beach.