Roughly 68% of the world's population cannot digest lactose properly. If you're one of them, you might be wondering what lactose intolerance even is. What does it mean to have a lactose intolerance issue? What symptoms of lactose intolerance should you look out for? If you can't comfortably consume dairy foods, is there anything you can do about it?

What is Lactose Intolerance?

If you have lactose intolerance, then it means you cannot completely digest the sugar found in dairy foods. (This milk sugar is called "lactose.") This usually happens because your small intestine doesn't produce enough of an enzyme called lactase, ultimately making digesting lactose difficult for your body.

We want to point out that there is lactose intolerance and lactose malabsorption. While they're often used interchangeably, they're not the exact same thing.

Importantly, lactose malabsorption happens when the small bowel can't absorb ingested lactose because of a lactase deficiency. You can have a lactose malabsorption issue without also having lactose intolerance.

Learn about the nine most common food allergens.

The 4 Main Types of Lactose Intolerance

Lactose intolerance can be broken down into four major types:

1. Primary lactose intolerance: There's a lactase deficiency in the small intestine. Primary lactose intolerance is the most common type.

2. Secondary lactose intolerance: This happens due to a disease or injury to the small intestine. (More on this in a moment!)

3. Congenital lactose intolerance: Lactase production is low from birth.

4. Developmental lactose intolerance: This happens as a result of premature birth and the small intestine being underdeveloped. As the intestine gets stronger, it can produce more of the lactase enzyme.

While there is no real cure for lactose intolerance, depending on the circumstances, you can "outgrow" it with time.

Is Lactose Intolerance a Food Allergy?

Surprisingly, no — lactose intolerance isn't an allergy.

If you have a milk allergy, for example (or any allergy, for that matter), when you consume milk, your immune system responds. It thinks that it's encountered an invader, so it springs into action and produces antibodies to protect you.

This is why you experience an allergic reaction that might manifest as itchy skin, watery eyes, or a stuffy nose.

Furthermore, with an allergy, even just a little exposure to that allergen can trigger symptoms.

On the other hand, with lactose intolerance, there is no immune system response. Plus, while every individual is different, many people can consume a small amount of dairy foods and not experience any lactose intolerance symptoms.

Regardless, the key difference is the immune reaction. If there's no immune reaction, it's not an allergy. It's (potentially) lactose intolerance.

Learn more about the difference between a food allergy and food intolerance — what's the difference?

Are You Lactose Intolerant Because of a Parent?

You can inherit lactose intolerance from a relative, although we want to note that if your parent has lactose intolerance, you won't automatically have it yourself. There are many factors, including non-genetic ones.

For instance, trauma to the small intestine that makes it harder to make enough lactase can lead to secondary lactose intolerance. Examples include Crohn's disease and celiac disease. Small intestinal bacterial overgrowth (SIBO) is also a potential cause. This happens when too many bacteria make their way from the colon to the small intestine. SIBO symptoms can be improved with dietary changes, which can then improve the symptoms of lactose intolerance.

This is why it's possible to develop lactose intolerance even if you have never had a problem eating dairy foods in the past.

Read our blog: How Many People Have Celiac Disease?

What Do Lactose Intolerance Symptoms Look Like?

Lactose intolerance isn't typically dangerous but simply uncomfortable since it leads to digestive symptoms.

Symptoms of lactose intolerance can include:

• Bloating and gas

• Diarrhea

• Nausea and vomiting

• Belly gurgles

• Stomach cramps/abdominal pain

How Do You Know If You Can't Digest Lactose?

If you eat dairy products and experience any of the above symptoms of lactose intolerance, then your small intestine might not be producing enough lactase to properly digest milk products.

Are you unsure if you're lactose intolerant or dealing with an actual allergy? Allergy testing can help.

eNational Testing's allergy and sensitivities panel checks for all major allergies, including milk. We have more than 2,700 locations across the nation, and your test results will be emailed to you within two to four business days.

Find a testing center near you.

There are other ways to have lactose intolerance diagnosed, too, including a hydrogen breath test, during which your breath is tested every 15 minutes for a few hours after drinking a lactose solution to measure hydrogen levels. An excessive amount of hydrogen could mean that you're lactose intolerant.

Can You Cure Lactose Intolerance?

Currently, there is no known cure or treatment for lactose intolerance, although there is medicine that can help alleviate the symptoms. Even though dairy products can be a part of a healthy diet, most people with lactose intolerance simply choose to avoid them or stick with lactose-free dairy products.

If you're dealing with secondary lactose intolerance and can address the underlying cause (like repairing any damage done to the small intestine), then it is possible that the small intestine can start producing more of the lactase enzyme once again, and you can comfortably consume milk and dairy products.

Thankfully, these days, there are so many delicious options that make it easier than ever for people who don't eat dairy products. Almond, oat, cashew, and soy milk are all lactose-free milk alternatives. Head to your grocery store to find lactose-free alternatives to cheese, yogurt, ice cream, and other foods.

Restaurants are even getting better at providing gut-friendly menu options like pizza, pasta, and sandwiches made with non-dairy cheese, better catering to people with lactose intolerance, vegans, and other plant-based folks.

You can better manage lactose intolerance and take great care of your digestive tract by avoiding consuming lactose-containing foods. You're never limited to dairy products!