Lactose Intolerance Versus Dairy Allergy

Although both require the elimination of dairy products from your diet, and some of the symptoms overlap, lactose intolerance and dairy allergy are not the same thing. Lactose intolerance is a problem of the digestive system; dairy allergy is a problem of the immune system.

Lactose Intolerance

Lactose intolerance has two main causes: lactase deficiency and lactose malabsorption. Lactase is an enzyme in the small intestine that breaks down milk sugar -- lactose. Lactose malabsorption can be caused by lactase deficiency and occurs when undigested lactose moves to the colon, where bacteria begin to break down the lactose, creating fluid and gas.

Like many conditions, lactose intolerance varies from person-to-person. Most people can consume a certain amount of lactose without having symptoms, but that amount varies by individual. There are four different types of lactose intolerance:

1. Primary lactase deficiency - the most common - involves a decline of lactase production over time, usually beginning about two years old
2. Secondary lactase deficiency - results from an injury to the small intestine
3. Developmental lactase deficiency - affects premature babies and is usually temporary
4. Congenital lactase deficiency - the rarest form, in which the small intestine produces very little or no lactase from birth

Particular populations are more likely to have lactose intolerance. About 65% of all humans have some level of lactose intolerance, and it’s most common in people of East Asian descent. People of Northern European descent, however, are far less likely to be lactose intolerant, and only about 5% of that population has the condition.

Most people with lactose intolerance can manage it with dietary modifications. Some dairy products, such as hard cheese, contain little lactose, but others, such as milk, contain more. Many people with lactose intolerance can consume yogurt but not milk, even though the two contain roughly similar amounts of lactose.

The experts at Danvers Family Doctors can help you create a dietary plan that meets your nutritional needs and helps you avoid discomfort.

Dairy Allergy

Although dairy allergy may result in some of the same symptoms as lactose intolerance, it is a problem of the immune system and can be more serious, even life-threatening. In addition to gas, bloating, cramps, nausea, and diarrhea, people with dairy allergy may experience breathing problems, hives, and swelling of the throat and lips.

Dairy allergy is one of several food allergens that are responsible for the most serious reactions. It is entirely possible to have an allergy to cow’s milk, but not to other dairy products.

Dairy allergy appears most often in children, and approximately 2-3% of children under the age of three years is allergic to milk. About 80% of children grow out of milk allergy by the age of 16.

The only way to manage a dairy allergy is to avoid dairy products, particularly anything containing casein and whey, both of which are types of milk protein. About 30% of children with a food allergy are allergic to more than one food.

Anaphylaxis, a severe, life-threatening allergic reaction, can result from dairy allergy. The healthcare providers at Danvers Family Doctors may suggest having injectable epinephrine on hand for anyone with dairy allergy.