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Pediatric and Adult Nutrition in Chronic Diseases, Developmental Disabilities, and Hereditary Metabolic DisordersPrevention, Assessment, and Treatment$

Shirley W. Ekvall and Valli K. Ekvall

Print publication date: 2017

Print ISBN-13: 9780199398911

Published to Oxford Scholarship Online: April 2017

DOI: 10.1093/acprof:oso/9780199398911.001.0001

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Lactose Intolerance

Lactose Intolerance

(p.341) 50 Lactose Intolerance
Pediatric and Adult Nutrition in Chronic Diseases, Developmental Disabilities, and Hereditary Metabolic Disorders

Patricia J. Becker

Alison Cassin

Scott Pentiuk

Oxford University Press

Abstract and Keywords

This chapter discusses lactose intolerance, including biochemical abnormalities and factors to be considered in nutritional evaluation. The diagnosis and dietary management of lactose digestion and absorption, primary lactose intolerance, lactase persistence and nonpersistence, and secondary lactose intolerance are described. Acute gastroenteritis, cow’s milk enteropathy, short bowel syndrome, lactose deficiency due to other gastrointestinal conditions, and small intestinal bacterial overgrowth are specifically discussed.

Keywords:   lactose intolerance, primary intolerance, short bowel syndrome, small intestinal bacterial overgrowth

Food intolerances are common but often difficult to identify. Lactose maldigestion is reported to be the most common food intolerance, affecting 80% of African-Americans, 50% of Hispanic Americans, and 15% of the Caucasian-American population.1 The true prevalence of lactose intolerance is more difficult to identify because of the limitations in diagnosis and the lack of consistent definition, standarized assessment methodology, and symptomatology.2

Biochemical Abnormalities

Lactose intolerance is a type of maldigestion in which a standard dose of the sugar lactose cannot be tolerated without development of gut dysfunction. Diarrhea, abdominal pain, bloating, and flatulence are the most common symptoms.

The lactase enzyme is a membrane-bound enzyme located in the brush border or microvilli of the small bowel. The lactase enzyme hydrolyzes lactose into its constituent monosaccharides, glucose and galactose, which are then transported across the brush border of the small intestines.3 In individuals with lactase deficiency, up to 75% of ingested lactose remains intact. The lactose that is not digested in the small bowel passes rapidly into the colon, where it is converted to short-chain fatty acids and hydrogen or methane gas by colonic bacteria. The short-chain fatty acids, butyrate, acetate, and propionate are utilized by both colonocytes and bacteria as an energy source. This lactose salvaging in the newborn gut allows for support of beneficial gut flora and increased nutrient absorption for the infant.4,5 In the adult with lactase insufficiency or deficiency, this mechanism allows for the ingestion, digestion, and absorption of small amounts of lactose without symptoms of intolerance. It is when this mechanism becomes overwhelmed that excess gas is produced, and this is the source of hydrogen production and gastrointestinal symptoms.6,7,8

Lactose intolerance may be either primary or secondary. The disorders of primary intolerance include developmental lactase deficiency, congenital lactase deficiency (CLD), and lactase nonpersistence, with developmental and late-onset forms.4 Secondary lactose malabsorption is the result of gut dysfunction due to mucosal injury.

Factors To Be Considered in Nutrition Evaluation

The goal of therapy in secondary lactose intolerance is to treat the disease that induced the intolerance. The capacity to tolerate lactose recovers once mucosal villi regenerate; dietary restriction may not be permanent once the primary illness has improved. However, the rate of recovery is variable and may not correlate with histological recovery of the absorptive surface. Intolerance may persist for months.

Lactose Digestion and Absorption in Infants, Children, and Adults Compared with other mammalian species, human milk has the highest concentration of the disaccharide lactose. Lactose is the major carbohydrate source in the neonatal period. It is the preferred carbohydrate for infants because it enhances the absorption of minerals such as calcium and magnesium and the growth of lactobacilli and bifidobacteria in the intestinal tract.9,10,11

Primary Lactose Intolerance: Congenital

CLD is a rare autosomal recessive disorder characterized by the absence of lactase activity in the small bowel. This condition, described by Holzel et al.12 in 1959, manifests at birth with explosive, watery diarrhea and can, although very rarely, lasts throughout life. The symptoms occur immediately on introduction of lactose in the neonatal period due to the complete absence or severe reduction of lactase activity. Before the introduction of lactose-free infant formula, this disorder was life-threatening.13,14

Primary Lactose Intolerance: Developmental

Lactase activity increases from the early months of fetal life, reaching peak activity shortly after birth. Twenty-five percent of 1-week-old term infants have lactose malabsorption.15 Even if enzyme levels are low, colonic bacteria can salvage the lactose that is not digested in the small intestine of very small premature infants. As much as 66% of ingested lactose enters the colon in premature infants, and the low lactase activity at birth in these infants has little clinical significance. Despite the lag in development of enzyme activity, the term and even the premature infant can tolerate the levels of lactose in human milk and formulas.4,5

Lactose Intolerance in Children

The 1978 American Academy of Pediatrics statement, “The Practical Significance of Lactose Intolerance in Children,” and its 1990 update stated that the major concerns were (1) the prevalence of lactose intolerance at specific ages in particular populations, (2) the relationship between intolerance and the quantity of milk consumed, (3) the response to hydrolyzed lactose products, and (4) the absorption of other nutrients in the presence of lactose that has surpassed digestive capacity.15,16,17

Significant problems are not usually seen in children with lactose malabsorption due to primary late-onset lactase deficiency. Most of these children experience no adverse effects from moderate milk intake. Studies have shown that most individuals can tolerate milk and milk products in small amounts and with other foods.7,9,18 Factors such as fat content, amount, and timing of lactose ingestion determine the tolerance and resulting symptoms. In these children, cultured and fermented dairy products such as aged cheese (e.g., cheddar, Swiss, Parmesan) and yogurt are often tolerated.

Live-culture yogurt contains Lactobacillus bulgaricus and Streptococcus thermophilus, which provide beta-galactosidase.19,20 The degree of lactose reduction by bacteria found in yogurt can vary. Yogurt is well tolerated for other reasons. The consistency of yogurt slows gastric emptying and the fermentation process removes some of the lactose, resulting in a lower lactose content compared with nonfermented dairy products. Milk containing Lactobacillus acidophilus may also be tolerated and may have beneficial effects for individuals with lactose intolerance.

Adults: Primary Lactase Persistence and Nonpersistence

The occurrence of lactose persistence and nonpersistence is genetically dictated and therefore related to ethnicity. Caucasians of European descent have a high occurrence of lactase persistence.

Lactase nonpersistence is the genetically regulated reduction of lactase activity; it is the underlying cause of primary lactose intolerance. The majority of the world’s population exhibit low intestinal lactase levels after weaning before 5 years of age.10,21,22 The diagnosis of lactose intolerance is most often suspected in this population with the (p.342) presentation of abdominal distention, bloating, flatulence, and diarrhea after the ingestion of foods containing lactose.1,23,24

Children from Thailand and Bangladesh show decreased enzyme activity as early as 2 years of age, whereas African Americans, Asians, and Latin Americans show adult values in children after the first decade of life.15

Secondary Lactose Intolerance

Secondary lactose intolerance occurs in individuals who by age or heredity have normal lactase activity; it is caused by conditions that negatively impact the intestinal mucosa. These conditions include malnutrition, acute gastroenteritis, cow’s milk enteropathy, small bowel syndrome, and celiac disease.


Inadequate nutrient intake that results in malnutrition affects all organs including the gut. Reduced villi height and villi atrophy result in diminished brush border enzymes, with decreased lactase activity in severe cases of malnutrition. The return of lactase synthesis occurs with the occurrence of adequate nutrient intake and the replenishing of nutrient stores.

Acute Gastroenteritis

Organisms such as viruses, parasites, and bacteria can injure the brush border. Diarrhea associated with gastroenteritis is common in infancy. In infants and children with giardiasis, the giardia adhere to the microvillus membrane, leading to overgrowth on the surface of the intestine, mucosal injury, and lactose intolerance. Rotavirus is also associated with temporary lactose intolerance.9,15

Breast-feeding should not be interrupted. Data suggest that for non–breast-fed infants and young children in the hospital setting, lactose-free feedings can be considered in the management of gastroenteritis. This therapy may reduce the duration and severity of diarrhea.25,26

Cow’s Milk Enteropathy

Children with milk protein allergy may also have a secondary lactase deficiency. Investigations have demonstrated reduced disaccharidase activity after mucosal damage due to sensitivity to cow’s milk or soy protein.27,28 Gastrointestinal symptoms such as loose stools and abdominal distention occur in both cow’s milk protein allergy and lactose intolerance. However, because milk allergy has an immunological etiology, vomiting, dermatological symptoms, and respiratory reactions occur only in milk allergy.

Short Bowel Syndrome

Lactose intolerance may be present in infants and children with short bowel due to damage to the intestinal mucosa, decreased absorptive surface area, and shortened transit time. A lactose-free diet may be beneficial if these conditions are present. Several studies have shown that adults with short bowel syndrome tolerate small amounts of lactose in milk or yogurt without symptoms or differences on breath hydrogen testing.29

Lactose Deficiency due to Other Gastrointestinal Conditions

Patients with active Crohn’s disease may also experience lactose maldigestion and malabsorption due to decreased brush border lactase levels or other mechanisms. Patients newly diagnosed with celiac disease may have temporary lactose intolerance as a result of damage to the lining of the small intestine. After ingestion of lactose, patients with celiac disease may complain of rumbling bowel sounds, distention, flatus, and osmotic diarrhea. This resolves once the intestine heals in response to the gluten-free diet.

Radiation therapy can have effects on the gastrointestinal tract in children with cancer. This can contribute to some degree of lactose intolerance. Lactose malabsorption can be a cause of diarrhea in patients with human immunodeficiency virus (HIV) infection or acquired immune deficiency syndrome (AIDS). Recurrent abdominal pain in children also may be caused by lactose maldigestion.28,30

Small Intestinal Bacterial Overgrowth

In general, symptoms of lactose intolerance are produced when lactose is digested by gut bacteria. In the normal bowel, these microbes are located in the colon. For individuals with small intestinal bacterial overgrowth (SIBO), lactose intolerance occurs when undigested lactose encounters bacteria. This may result not from lactose deficiency but from premature exposure of lactose to bacteria in the small bowel, which leads to increased production of gas and short-chain fatty acids plus increased transit time and osmotic load.31

Signs and Symptoms

Symptoms of lactose intolerance include abdominal pain, cramps, distention, nausea, flatulence, and diarrhea; they occur within 30 minutes to 2 hours after eating or drinking foods containing lactose. The severity of symptoms varies, depending on the amount of lactose each patient can tolerate (influenced by physiological and psychological factors). Symptoms depend on the level of lactase activity, the amount of lactose ingested, meal composition, and other factors.

Diagnosis of Lactose Intolerance

Lactose intolerance can be diagnosed by several methods, testing either for absorption or for malabsorption.

Lactose Absorption Test

The capacity to absorb lactose can be measured by administering a dose of lactose and measuring blood glucose levels after 0, 60, and 120 minutes. A 50-g dose of lactose that results in an increase in blood glucose of 20 mg/dL along with the development of the gastrointestinal symptoms of lactose malabsorption is diagnostic. False-negative tests occur in individuals with diabetes, delayed gastric emptying, or SIBO small intestinal bacterial overgrowth.6,17,20,21,30 This test is cumbersome and requires blood sampling to determine serum glucose levels. It has largely been replaced by the hydrogen breath test.31,32,33

Breath Hydrogen Test

The breath hydrogen test is the most accurate test for identifying lactose malabsorption; it is simple and noninvasive. Hydrogen in breath is measured after administration of a lactose load. The lactose dose varies (usually 1–2 g/kg, with a maximum of 50 g). The physiological dose is 12 g lactose (the amount in 1 cup of milk), and this is often the dose used for testing. A positive test is indicated by a rise of 20 ppm or more in expired hydrogen above baseline. Samples are collected before administration of lactose and in 30-minute intervals for 3 hours thereafter.

A diagnosis of lactose maldigestion does not predict the occurrence of symptoms. The test is also used to determine other forms of carbohydrate maldigestion or malabsorption and SIBO.6,18,20,21,28 In individuals with suspected SIBO, a hydrogen breath test using lactulose may be required to differentiate the two disorders.6,31,32

Genetic Test

A new genetic test It detects the single nucleotide polymorphism C/T 13910 of the lactase gene (LCT) on chromosome 2. This DNA variant has been associated with adult-type hypolactasia. Use of this test would enable children to be diagnosed without lactose challenge.

Stool Acidity Test

A stool acidity test can be used in infants and young children. This test measures lactic acid and other short-chain fatty acids present in the stool that are derived from undigested lactose fermented by bacteria. The test uses pH measurements (pH ≤5.5 is abnormal). However, this test is not specific for lactose intolerance; a positive test is also present in people with other carbohydrate malabsorption disorders.6,18,21,27,30

Intestinal Biopsy

Biopsies may not always yield abnormal results, because lactase deficiency after mucosal injury may be patchy. Lactase measurement with (p.343) intestinal biopsies is time-consuming and invasive. However, it may be useful if the patient is already undergoing endoscopy as part of his or her evaluation.

Empirical Lactose Avoidance

A simple lactose avoidance test may aid in diagnosis. Patients avoid lactose for 1 to 2 weeks and their symptoms are tracked. This test is not as specific as others, but families often prefer it.

Dietary Management

Medical Nutrition Therapy

Treatment for lactose intolerance aims to prevent the gastrointestinal symptoms associated with lactose malabsorption. Optimal diet therapy for lactose intolerance involves determination of a nonoffending, individualized diet. This can be achieved by using a combination of tolerated lactose-containing foods, enzymatically pretreated dairy products, lactase enzyme supplements taken concurrently with milk products, or plant-based milk alternatives and dietary supplementation to meet nutrient needs despite dietary restrictions.

Proper dietary management depends on the individual’s diagnosis (i.e., primary versus secondary lactose intolerance). Complete avoidance of lactose, the offending carbohydrate, relieves symptoms in all cases of lactose intolerance. Because there is much variability in lactose tolerability among those with lactose nonpersistance or secondary lactose intolerance,9 the degree of dietary lactose restriction necessary for symptom relief depends on the etiology of lactose malabsorption. Individuals with CLD require more stringent lactose restriction than, for example, those with lactose nonpersistance or secondary lactose intolerance, who preserve some lactase and therefore the ability to digest lactose in small quantities. For this reason, the degree of dietary restriction should be tailored to the individual. For those with secondary lactose intolerance, lactose restriction is no longer required once the underlying condition causing malabsorption is resolved.

Lactose restriction involves reducing or completely restricting lactose-containing foods, such as cow’s milk products, from the diet. Depending on individual tolerance, avoidance of convenience foods to which whey, milk, milk solids, or lactose has been added may also be required. Other mammalian milks, such as goat, sheep, or mare’s milk, are not lactose-free. Lactose is less sweet than other sugars, so it is used in commercial food products as a food thickener, to improve the appearance and texture of certain foods, or to enhance the solubility of instant drink mixes and powdered substances. Lactose can also be present in tablet medications, although the amount of lactose ingested in this form (<500 mg) rarely causes gastrointestinal symptoms.34 Dairy products pretreated with lactase enzyme and thus rendered lactose-free are widely available in supermarkets and are well tolerated by individuals with lactose intolerance. These products are covered by the Women, Infants and Children (WIC) supplemental nutrition packages, and less expensive store brands are also available for purchase by those who do not qualify for WIC benefits.9

Published recommendations for dietary lactose restriction vary widely. More conservative recommendations suggest complete lactose elimination for 2t o 4 weeks to achieve symptom relief,6 followed by gradual reintroduction of low-lactose cheeses and yogurt and progressing to other milk products as tolerated. Other studies define a low-lactose diet as one that restricts lactose to less than 6 g per meal35 or less than 12 g per day.36

Because some lactose-intolerant children and adults can tolerate 4 to 8 ounces of cow’s milk without developing symptoms, it has been suggested that 12 g of lactose (or 8 oz of milk) can be easily tolerated by those with lactose intolerance.37,38,39 Blinded studies in adults with self-reported lactose intolerance suggest that at least 12 g lactose can be tolerated at one occasion without development of symptoms,39,40 and up to 18 g lactose can be tolerated when taken with other foods.41 Consumption of milk and dairy foods during meals with other foods may slow gastric emptying and promote tolerance.42,43 Many lactose-intolerant individuals can tolerate milk chocolate44 or fluid milk with cocoa added.45 Plain yogurt is usually well tolerated because the active cultures in yogurt partially digest lactose before consumption.46,47 The continuing presence of some degree of lactose in the diet may promote lactose tolerance due to adaptation of colonic flora.9,41

Drug therapy may alternatively improve an individual’s ability to tolerate lactose-containing foods. Lactase-replacement supplements can be taken orally when consuming milk products to prevent gastrointestinal symptoms by breaking down lactose into glucose and galactose for improved intestinal absorption.48 Supplement dosing and efficacy vary among brands.49 Probiotics may promote tolerance via alterations in intestinal flora.50 Some probiotics contain beta-galactosidase, which directly enzymatically digests dietary lactose. Other probiotics promote colonization of bacteria that hydrolyze lactose and prevent fermentation by other colonic bacteria, thus avoiding gastrointestinal symptoms.51

Milk and dairy products should not be entirely eliminated from the diet without appropriate substitution, because these foods are excellent sources of calories, protein, vitamins A and D, riboflavin, calcium, phosphorus, and other minerals. Children on milk-restricted diets have lower intake of these nutrients.52 Although lactose itself has not been shown to directly affect calcium absorption, studies suggest that lactose-free diets prescribed to children are low in calcium and result in low bone mineral density.53,54 Additionally, long-term data show that children on milk-restricted diets have shorter stature55 and lower weight55,56 than children on full diets. Nut- and grain-based milk alternatives such as rice, soy, almond, or coconut beverages are completely lactose free but often do not contain the nutrients found in milk unless fortified with calcium, riboflavin, and vitamins A, D, and B12. Nut- and grain-based milks are hypocaloric and have lower protein and fat content compared with cow’s milk. Therefore, they are not appropriate replacements for toddlers or children with low dietary protein and fat intake from other sources (Table 50–1). Soy and soy products have many health benefits and can be used in children’s diets; their protein content comparable that found in standard cow’s milk. Depending on diet composition and nutrient needs based on age (Table 50–2), calcium supplementation may be required if milk is eliminated from the diet and calcium-rich foods are not consumed (Table 50–3); they should be recommended judiciously, however, because excessive calcium intake in young children consuming milk alternatives and calcium supplements may promote iron deficiency.57

Table 50–1. Comparison of Enriched Plant-Based Milk Alternatives to Whole Cow’s Milk (per 8 oz)



Protein (g)

Fat (g)

Vitamin D (IU)

Calcium (mg)

Whole Milk










































Table 50–2. Lactose-Free Formulas, Milk Substitutes, and Other Calcium Sources

Lactose-Free Formulas Infant

Lactose-Free Formulas Pediatric

Milk Substitutes

Cow’s Milk-Based

Cow’s Milk-Based

Cow’s Milk-Based

Similac Sensitive Spit-Up


Lactaid Milk

Parent’s Choice Gentle


Dairy Ease Milk

Boost Kids Essentials

Nutren Junior

Compleat Pediatric




Enfamil Prosobee

Bright Beginnings Soy


Similac Isomil

Enfagrow Toddler Soy

8th Continent

Earth’s Best Organic Soy

Similac Grow & Go Soy


Gerber GoodStart Soy




Other Plant-Based


Peptamen Junior

Rice Dream


Almond Breeze


SoDelicious Coconut



Pacific Oat Milk


Elecare Junior

Tempt Hemp Milk

Neocate Infant

Neocate Junior

Pure Almond


Vivonex Pediatric

Table 50–3. Lactose-Free Diet*

Food Groups




See also milk and milk products. Milk-free cocoa, fruit juices, lactose-free carbonated beverages and fruit drinks, coffee and tea, decaffeinated coffee

Milk beverages, instant coffee and tea containing lactose, powdered soft drinks and artificial drinks containing lactose, instant chocolate drinks

Breads and cereals

Any that do not contain milk or milk products (Italian, Vienna, French, Jewish bread), saltine and graham crackers, rusk, Ry-Krisp and Ritz crackers, other snack chips without milk, infant cereals, cooked or dry cereals without added milk

Muffins, biscuits, waffles, sweet rolls, pancakes, cereals, bread and crackers containing milk and milk products; instant cereals containing lactose


Fruit ices, popsicles, gelatin dessert, angel food cake, homemade cakes, fruit pies, cookies made without milk or milk products

Commercial cakes, cookies, and dessert mixes, custard pudding, ice cream, ice milk, sherbet, yogurt, frozen yogurt, most soufflés and mousses, desserts containing chocolate, caramel, reduced-calorie desserts made with sugar substitute containing lactose


Margarine and dressings that do not contain milk or milk products, vegetable oils, shortenings, mayonnaise, bacon

Margarine, butter, sauces and dressings containing milk or milk products; cream, half-and-half, whipped cream, cream cheese, sour cream; gravies made with milk, cream sauces and cheese, cheese dips

Fruits and juices

All unless processed with lactose

Fruits and juices containing milk, lactose, or whey

Meat, fish, poultry, eggs, legumes

Plain beef, chicken, fish, turkey, seafood, lamb, veal, pork, ham, plain eggs, legumes, kosher meat products, dried peas, beans, lentils

Creamed or breaded meat, fish, or poultry; lunch meats, sausages and frankfurters containing milk or milk products; creamed or scrambled eggs or omelettes prepared with milk

Milk, milk products, substitutes

Nutramigen and soybean milk used as milk substitutes (e.t., Prosobee, Isomil, Nursoy), Ensure, Pediasure and other lactose-free, high-calorie canned supplements; milk treated with lactase enzyme such as LactAid, Vitamite, nondairy creamers

Cow’s milk–based infant formulas, low-fat milk, nonfat milk, whole milk, powdered milk, condensed and evaporated milk, buttermilk, goat milk, yogurt, cottage cheese, cheese, ice cream, ice milk, sherbet, malted milk, instant breakfast, hot chocolate, imitation milks

Potato, rice, pasta

White and sweet potatoes, yams, macaroni, noodles, spaghetti, rice

Any creamed or breaded potato, rice, or pasta; mashed or instant potatoes made with milk, macaroni and cheese mixes


Clear broth and bouillon-based soups, other soups made without milk or milk products

Cream soups, chowders, and commercial soups containing milk, cream, or cheese


All plain vegetables

Vegetables in cream or cheese sauce

Miscellaneous products

Flavorings, extracts, herbs, spices, salt, pepper, condiments, pickles, olives, sugar, jam, jelly, marmalade, preserves, honey, syrup, candy made without milk, popcorn, potato chips, corn chips, pretzels, coconut, nuts, peanut butter; pure cocoa powder, nondairy creamers and whipped toppings

Candies containing cream, milk, lactose, or chocolate; caramels, toffee, butterscotch, or peppermint candies, frosting; diet sugars and chewing gum containing lactose; frozen dinners, Italian dishes, quesadillas

(*) Lactose is found in milk and milk products. Labels should be read carefully; any product that contains milk, milk solids, dry milk solids, lactose, or whey may need to be excluded. Lactose is also frequently used as a filler in many products, such as instant coffee and tea, and in some medicines. Individuals with lactose intolerance may be able to eat “Lactose-Containing” foods in limited amounts.

Indications for Lactose-Free Infant Formulas

Lactose-free infant formulas have gained popularity in the United States,58 but routine use is warranted only in certain cases. The degree and duration of lactose restriction depend on the etiology of lactase deficiency or lactose malabsorption. (p.344)

Primary CLD requires prolonged adherence to a lactose-free diet, and in infancy this easily accomplished with a lactose-free, milk protein–based infant formula or a soy formula, which is naturally lactose free.9 Developmental (neonatal) lactase deficiency resulting from prematurity can be managed by with the use of lactase-treated feeds or low-lactose formula.59 However, human milk and standard premature infant formulas do not seem to have adverse effects in premature infants and may be used safely.60

The utility of lactose-free formulas in infants with secondary lactase deficiency is questionable. For infants with lactose intolerance secondary to malnutrition, provision of lactose-containing formula may promote lactose tolerance and improve growth outcomes.61 However, the utility of lactose-free formula for infants with postinfectious diarrhea is unclear. A meta-analysis found that children with diarrheal illness can continue to safely consume human milk or standard, lactose-containing formula.62 However, in malnourished infants or infants younger than 3 months of age with acute infectious diarrhea, a lactose-free formula may reduce the duration of diarrhea.63 As diarrhea resolves, infants may be offered their previously tolerated, lactose-containing formula. If the infant is breast-feeding, the mother can continue nursing. All soy protein–containing formulas are lactose-free and can be used for refeeding if diarrhea is prolonged. Despite widespread use, lactose-free formulas for treatment of presumed lactose intolerance resulting from colic, fussiness, and gas may not be warranted.64

Summary and Follow-up

The goal of medical nutrition therapy for lactose intolerance is to prevent gastrointestinal symptoms while continuing to provide adequate nutrition. An individualized management plan may include a combination of lactose restriction and lactase supplementation with appropriate food or nutritional supplements as needed. Achieving the least restrictive diet that does not elicit symptoms is the ultimate goal to promote optimal nutrition and quality of life.

(p.345) References

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