Lactose intolerance is the inability to break down a type of natural sugar called lactose. Lactose is commonly found in dairy products, such as milk and yogurt. You become lactose intolerant when your small intestine stops making enough of the enzyme lactase to digest and break down the lactose. When this happens, the undigested lactose moves into the large intestine. The bacteria that are normally present in your large intestine interact with the undigested lactose and cause symptoms such as bloating, gas, and diarrhea. The condition may also be called lactase deficiency.
Lactose intolerance is very common in adults, particularly those with Asian, African, and Hispanic ancestry. According to the Cleveland Clinic, more than 30 million American people are lactose intolerant. The condition isn’t serious but may be unpleasant. Lactose intolerance usually causes gastrointestinal symptoms, such as gas, bloating, and diarrhea, about 30 minutes to two hours after ingesting milk or other dairy products containing lactose. People who are lactose intolerant may need to avoid eating these products or take medications containing the lactase enzyme before doing so.
If you’re experiencing cramps, bloating, and diarrhea after drinking milk or eating and drinking milk products, your doctor may want to test you for lactose intolerance. Confirmatory tests measure lactase activity in the body. These tests include:
• Lactose intolerance test
A lactose intolerance test is a blood test that measures your body’s reaction to a liquid that contains high lactose levels.
• Hydrogen breath test
A hydrogen breath test measures the amount of hydrogen in your breath after consuming a drink high in lactose. If your body is unable to digest the lactose, the bacteria in your intestine will break it down instead. The process by which bacteria break down sugars like lactose is called fermentation. Fermentation releases hydrogen and other gases. These gases are absorbed and eventually exhaled. If you aren’t fully digesting lactose, the hydrogen breath test will show a higher than normal amount of hydrogen in your breath.
• Stool acidity test
This test is more often done in infants and children. It measures the amount of lactic acid in a stool sample. Lactic acid accumulates when bacteria in the intestine ferment the undigested lactose.
There’s currently no way to make your body produce more lactase. Treatment for lactose intolerance involves decreasing or completely removing milk products from the diet. Many people who are lactose intolerant can still have up to 1/2 cup of milk without experiencing any symptoms. Lactose-free milk products can also be found at most supermarkets. And not all dairy products contain a lot of lactose.
You may still be able to eat some hard cheeses, such as cheddar, Swiss, and Parmesan, or cultured milk products like yogurt. Low-fat or nonfat milk products typically have less lactose as well. An over-the-counter lactase enzyme is available in capsule, pill, drops, or chewable form to take before consuming dairy products. The drops can also be added to a carton of milk.
People who are lactose intolerant and not consuming milk or dairy products may become deficient in:
· vitamin D
Taking calcium supplements or eating foods that are either naturally high in calcium or are calcium-fortified is recommended.
Symptoms will go away if milk and milk products are removed from the diet. Read food labels carefully to detect ingredients that may contain lactose. Aside from milk and cream, look out for ingredients derived from milk, such as:
· whey or whey protein concentrate
· casein or caseinates
· dry milk solids or powder
Many foods that you would not expect to contain milk may actually contain milk and lactose. Examples include:
· salad dressings
· frozen waffles
· dry breakfast cereals
· baking mixes
· many instant soups
Milk and milk products are often added to processed foods. Even some nondairy creamers and medications may contain milk products and lactose. Lactose intolerance cannot be prevented. The symptoms of lactose intolerance can be prevented by eating less dairy.
Drinking low-fat or fat-free milk may also result in fewer symptoms. Try dairy milk alternatives such as:
· rice milk
Milk products with the lactose removed are also available.