Skipping milk-based foods is often essential when you're lactose-intolerant. Because your body doesn't have adequate levels of lactase, the enzyme required to break down lactose, you can experience some uncomfortable side effects when lactose hits your gut. While butter does contain the milk sugar known as lactose, it probably won't cause major issues, unless you're highly sensitive to lactose.
Lactose in Butter
Butter contains a mere 0.01 gram of lactose per tablespoon, explains New Orleans-based registered dietitian Molly Kimball. Just as a comparison, a full 8-ounce glass of cow's milk has as much as 13 grams of lactose, making it something you'll definitely need to skip if you're lactose-intolerant. Since butter only has a trace amount of lactose and you're not likely to consume large amounts of butter, it should be safe for you to eat if you have lactose intolerance.
What Can Happen
It is possible, however, that even small amounts of lactose can be an issue for some. You could experience severe abdominal cramps and bloating after eating something with butter. The little bit of lactose might also cause nausea and diarrhea. Gastrointestinal issues are sometimes signs of other ailments, including foodborne illness, food allergies and chronic bowel disorders such as Crohn's disease. Your doctor will have to conduct a physical exam to see if it's really lactose that's causing issues for you.
Treating the Problem
You can't cure lactose intolerance, although you can manage your symptoms with some lifestyle changes. Avoiding anything containing lactose, such as milk, ice cream and yogurt, is your first step. If you occasionally like to splurge on dairy foods, take an over-the-counter lactase enzyme ahead of time, with your doctor's permission. These enzymes break down the lactose from milk, minimizing or even preventing any negative side effects from occurring. If butter tends to cause a rumbling in your belly, consider taking a lactase enzyme before you consume butter as well.
Finding an Alternative
Finding a butter alternative is another option if even small amounts of lactose are troublesome. Many margarine products are dairy and lactose-free. They're often made with plant-based oils instead of milk, offering you a creamy flavorful substitute, while skipping the lactose. Read the label carefully, though. Watch for terms like "dairy-free" or "lactose-free" on the packaging to ensure the product doesn't contain lactose. You can also read through the ingredients list and look for milk, buttermilk, milk solids or other derivatives of milk. These types of spreads are ones you'll likely want to avoid.