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What does Lactose Intolerance mean?

Unlike a milk allergy, lactose intolerance doesn’t involve the immune system. It involves the inability to digest lactose, or the sugar found in milk and dairy products. Lactose intolerance, or lactose malabsorption, is more like the harmless, less aggressive but still awkward, little sister of milk allergy.

Typically, the inability to digest lactose is a result of your body not producing enough lactase, an enzyme produced in your small intestine. Lactase is responsible for breaking down lactose into glucose and galactose, two simple sugars that are absorbed into the bloodstream. Without an adequate amount of lactase in your system, lactose makes its way to you colon instead. The mixture of bacteria and unbroken down lactose causes the symptoms associated with lactose intolerance.

There are three different types of lactose intolerance:

Primary lactose intolerance: During infancy, people with this type of intolerance produced enough lactase in order to process the large amount of milk he or she consumed. As they entered adulthood and replaced milk with other beverages and food items, their lactase production decreased. Primary lactose intolerance is the most common type of intolerance

Secondary lactose intolerance: Less common than primary lactose intolerance, secondary lactose intolerance occurs after an illness, like Crohn’s or celiac disease, injury, or surgery that affects the small intestine. Once the small intestine is damaged, it starts to produce less lactase.

Developmental lactose intolerance: This rare type of intolerance is caused by an absence of lactase production. This biological abnormality is passed down through family members.


Symptoms of Lactose Intolerance

You will start to exhibit symptoms and signs of lactose intolerance between 30 minutes and two hours after eating or drinking dairy products. Symptoms include diarrhea, nausea, cramps, bloating, and gas. Vomiting may also occur, but that is not common.


Diet Changes

Currently, there is no way to increase your body’s production of lactase, but there are a few things you can do to avoid the discomfort of lactose intolerance. Try eating smaller servings of dairy products, consuming milk with other foods to slow the digestive process, tasting different dairy products with varying amounts of lactose, purchasing lactose‐free foods, or using lactase medicine to help you digest lactose.

with your doctor if the symptoms become harmful or painful, or if you’re worried about calcium deficiency.

Click here to find lactose‐free snack, lunch, and dinner ideas and recipes from Ornish Lifestyle Medicine.