Lactose Intolerance
Lactose Intolerance
by Debra Wood, RN
En Espa?ol (Spanish Version)
Definition
Lactose intolerance is the inability to digest significant quantities of lactose. Lactose is a sugar found in milk and other dairy products.
Causes
Lactose intolerance is caused by an inadequate amount of the digestive enzyme lactase. Lactase breaks down the sugar lactose into sugars the bloodstream can more easily absorb. When not fully broken down, lactose ferments in the colon (large intestine) and causes symptoms.
Colon
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Some people are born with the inability to make the enzyme lactase. Others develop the intolerance over time. Causes of lactose intolerance include:
Aging (lactase decreases as people age)
Gastroenteritis (or infection in the intestinal tract)
Nontropical and tropical sprue
Cystic fibrosis
Immunoglobulin deficiencies
Ulcerative colitis
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition.
Risk factors include:
Race: Black, Asian, or Native American
Ethnicity: Mediterranean or Jewish
Symptoms
Symptoms of lactose intolerance generally begin within two hours of consuming milk or other dairy products. The severity of symptoms depends on how much lactase your body produces and how much lactose you eat.
Symptoms include:
Nausea
Cramping
Bloating
Abdominal rumbling sounds
Gas
Diarrhea
Loose stools
Diagnosis
The doctor will ask about your symptoms and medical history and perform a physical exam. Often she will recommend a two-week trial period of eating no milk or milk products. If symptoms subside, you will be asked to consume milk products again. If milk causes symptoms to recur, you will be diagnosed with lactose intolerance.
Your doctor may also order some tests, including:
Hydrogen breath test—measures how much hydrogen is exhaled after drinking a high-lactose liquid
Stool acidity test—measures lactic acid in the stool for infants and small children
Lactose tolerance test—measures the amount of glucose (simple sugar that is created from lactose) absorbed two hours after drinking a high-lactose liquid, indicating how well the body is digesting lactose
Biopsy of the small intestine—involves removing and testing a sample of tissue to confirm lactase
deficiency
Treatment
Though gene therapy has been suggested as a future treatment, there is currently no way to increase the body’s production of lactase. Treatment today focuses on managing symptoms. Experts counsel against complete elimination of dietary lactose, especially in children and adolescents, because milk and milk products provide sources of calcium and other food elements that are otherwise hard to replace. If complete elimination is chosen, then careful replacement of calcium is essential for good health.
Treatments include:
Dietary Changes
Dietary changes include:
Keep a food diary of what you eat and what the reaction is. Discuss the findings with your doctor or a
dietitian.
Make gradual changes to your diet and record the results.
Try eating a smaller portion before giving up on a dairy product. Many people can tolerate 4-8 ounces of milk at a time and may have better tolerance for some of the following dairy products made from milk: Ice cream
Sherbet
Cream
Butter
Cheese
Yogurt
Aged cheese and yogurt may be easier to tolerate than other dairy products.
Try milk that is modified so it contains less lactose.
Ask a dietitian for help choosing substitutes for dairy products or recommending supplements to ensure that you eat enough calcium.
Nondairy foods rich in calcium include:
Salmon
Sardines
Oysters
Collard greens
Broccoli
Read product labels because other foods containing lactose include:
Breads
Baked goods
Processed cereals
Instant potatoes and soups
Margarine
Nonkosher lunch meat
Salad dressings
Candies
Pancake mixes
Frozen dinners
Other words that indicate lactose are:
Whey
Curds
Dry milk solids
Nonfat dry milk
Milk by-products
Be aware that some medicines may contain small amounts of lactose.
Medications
Your doctor may recommend lactase enzymes if you can tolerate only small quantities of lactose. The enzyme supplements come in liquid and chewable form. A few drops of the liquid added to milk, which is allowed to sit overnight, can decrease the amount of lactose in the milk by 70%-90%. Tablets are chewed or swallowed before eating foods that contain lactose.
Prevention
There are no guidelines for preventing lactose intolerance.
RESOURCES:
The American College of Gastroenterology
https://www.360docs.net/doc/271866608.html,/
American Gastroenterological Association
https://www.360docs.net/doc/271866608.html,/
CANADIAN RESOURCES:
The Canadian Association of Gastroenterology
https://www.360docs.net/doc/271866608.html,/default.aspx
Dietitians of Canada
http://www.dietitians.ca/
REFERENCES:
American College of Gastroenterology website. Available at: https://www.360docs.net/doc/271866608.html, . Accessed July 1, 2009. Dambro M. Griffith's 5-Minute Clinical Consult. Philadelphia, PA: Lippincott Williams & Wilkins; 1999. Feldman M. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 8th ed. St. Louis, MO: Mosby; 2005. Heyman MB. Lactose intolerance in infants, children, and adolescents. Pediatrics. 2006;118(3):1279-1286. Lactose intolerance. American Gastroenterological Association website. Available at:
https://www.360docs.net/doc/271866608.html,/wmspage.cfm?parm1=854 . Accessed July 1, 2009.
Lactose intolerance. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: http://digestive.n... . Published March 2006. Accessed July 1, 2009.
Montalta M, Curigliano V, Santoro L, et al. Management and treatment of lactose malabsorption. World J Gastroenterol. 2006;12(2):187-191.
National Institutes of Health. National Institutes of Health (NIH) 2010 consensus development conference statement on lactose intolerance and health. 2010 Feb 22-24;27(2).
Last reviewed September 2011 by Purvee S. Shah, MD
Last Updated: 9/1/2011