Lactose Intolerance

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What is Lactose Intolerance?

Lactose intolerance is caused by a decreased or absent enzyme called lactase. Lactase is an important digestive enzyme that breaks down lactose into two components called glucose and galactose, enabling lactose to be digested. When lactose cannot be digested, a natural gas called hydrogen is produced by natural bacteria in our small intestines and large intestines. Excessive amounts of hydrogen gas in our intestines can cause problems such as abdominal pain, excessive gas, abdominal distention, diarrhea, or nausea. The more lactose that is ingested by a lactose intolerant person, the more severe the symptoms. Symptoms usually occur 30 minutes to two hours after eating foods containing lactose.

What Causes Lactose Intolerance?

There are several reasons lactose intolerance can occur. It can be a congenital defect. That means a person may have been born without the enzyme lactase, necessary to break down lactose for digestion.  It can also occur by a secondary cause such as a malabsorptive disorder called celiac disease*. The most common reason people develop lactose intolerance is because they are not able to produce enough of the enzyme lactase. This usually occurs through adolescence and adulthood.

*Celiac Disease: Celiac disease is the inability to absorb nutrients from foods containing gluten. Gluten can be found in crackers, breads, pasta, wheat, barley, and rye. The symptoms for lactose intolerance are similar to that of celiac disease. If you think you may have an intolerance to gluten, please talk with your healthcare providers about getting tested for celiac disease.

The Hydrogen Breath Test: Testing for Lactose Intolerance:

A simple breath test can be done in the office to test for lactose intolerance. The over-production of gasses such as hydrogen is a result of the fermentation of lactose by bacteria in the large intestines. The hydrogen is absorbed through the bloodstream and excreted through the lungs. After you blow through a special device, the Hydrogen Breath Test can allow us to measure the amount of hydrogen in your lungs. An elevated hydrogen level alerts us to the possibility of lactose intolerance.

You must fast for 12 hours before your appointment. We ask that you take your medications as directed with a small sip of water the morning of the procedure. Please advise your health care provider if you are diabetic or if you have been on antibiotics within the last two weeks. You will be given an 8 oz. glass of milk to drink and a breath test will be obtained initially and again approximately three hours after ingestion. Detailed instructions will be provided at the time of the appointment.

Treatment for Lactose Intolerance:

Avoid foods containing milk products such as: milk, cheese, yogurt, cottage cheese, and coffee creamers.

There are also foods that have hidden lactose in them such as: bread and other baked goods, processed breakfast cereals, instant potatoes, soups, breakfast drinks, margarine, lunch meats (other than kosher), salad dressings, candies and other snacks, mixes for pancakes, biscuits, cookies and powdered meal replacement supplements.

** Consider consulting with a registered dietician for a complete list of foods to avoid.

It is important to supplement calcium in your diet for bone health, some examples are: dark lettuce greens and broccoli, fish such as salmon, sardines, or tuna, soymilk, oranges, pinto beans, or a daily calcium supplement.