Nutrition & Diet Therapy (7 th Edition) Carbohydrate- & Fat-Modified Diets for Malabsorption Chapter 19

Nutrition & Diet Therapy (7 th Edition) I. Malabsorption Syndromes Malabsorption disorders- most harmful to nutrition status and result in: –Nutrient deficiencies –Weight loss –Serious complications Disorders associated with malabsorption –Genetic disorders –Pancreatic disorders –Intestinal disorders –Intestinal infections –Liver disease (bile insufficiency) –Surgeries Rarely involves single nutrient Treatment of malabsorption disorders (surgery and medications) may also weaken nutritional status

Nutrition & Diet Therapy (7 th Edition)

Malabsorption Syndromes cont’d Fat malabsorption –Causes Illness that interferes with production or secretion of bile (severe liver disease) or pancreatic lipase (pancreatitis, cystic fibrosis) Damage to intestinal mucosa (inflammatory disorders or radiation treatments) Motility disorders causing rapid gastric emptying or intestinal transit –Consequences: losses of food energy, essential fatty acids, fat-soluble vitamins, some minerals Weight loss Deficiencies of fat-soluble vitamins Formation of soaps by some minerals & unabsorbed fatty acids Bone loss from calcium deficiency Increased risk of kidney stones (Ca oxalates)

Nutrition & Diet Therapy (7 th Edition) Fat malabsorption (con’t) –Dietary adjustments: fat-restricted diet Relief of abdominal symptoms (diarrhea & flatulence) Minimize loss of vitamins & minerals Fats should not be restricted more than necessary Alternative source of dietary fat: medium- chain triglycerides (MCT) MCT Triglycerides with fatty acids that do not require digestion; can be absorbed without lipase or bile

Nutrition & Diet Therapy (7 th Edition) Malabsorption Syndromes cont’d Bacterial overgrowth –Gastric acid & peristalsis protect stomach & small intestine from bacterial overgrowth –When overgrowth does occur, disrupts fat digestion & absorption –Eventually results in deficiencies of fat-soluble vitamins –Bacteria compete with vitamin B 12, impairing its absorption –Symptoms: chronic diarrhea, abdominal discomfort, bloating, weakness, weight loss

Nutrition & Diet Therapy (7 th Edition) Bacterial overgrowth (con’t) –Causes Impaired intestinal motility –Some types of gastric surgery –Strictures, obstructions & diverticula in small intestine Reduced secretion of gastric acid –Atrophic gastritis –Acid-suppressing medications –Acid-reducing surgery –Treatment Antibiotics Surgical correction of anatomical defects Dietary supplements-fat soluble vitamins, Ca, vit B12

Nutrition & Diet Therapy (7 th Edition) II. Lactose Intolerance High incidence: approximately 75% of population worldwide –Rarely serious –Most individuals (with lactose intolerance) can tolerate milk if consumed with other foods & limit amount consumed at one time Cause: reduction or loss of lactase, enzyme that digests lactose in milk products Prevalent among certain ethnic groups: Asians, African Americans, Native Americans, Ashkenazi Jews, Latinos Dietary management –Gradually increased consumption of lactose- containing products –Divide milk intake throughout the day –Consume milk with meals –Chocolate milk may be better tolerated than plain –Aged cheeses well tolerated (little lactose content) –Yogurts with live bacterial cultures that aid in lactose digestion –Low lactose or acidophilus milk? –Addition of lactase preparation to milk or use of enzyme tablet before consumption

Nutrition & Diet Therapy (7 th Edition) III. Disorders of the Pancreas Maldigestive and malabsorption problems due to impaired secretion of digestive enzymes Pancreatitis –Inflammatory disease, resulting in damage to pancreatic tissue & release of enzymes –Acute pancreatitis Usually caused by gallstones, excessive alcohol use; also caused by high blood triglycerides, exposure to toxins Symptoms: severe abdominal pain, nausea & vomiting, abdominal distention Usually resolves within a week without complications MNT: NPO>clear liquids>low fat diet or hydrolyzed TF

Nutrition & Diet Therapy (7 th Edition) Pancreatitis (con’t) –Chronic pancreatitis may cause irreversible damage & loss of pancreatic function –Majority of cases (70%) of chronic pancreatitis caused by excessive alcohol consumption –Symptoms: severe abdominal pain; may be unrelenting & worsens when eating –Consequences Fat maldigestion Maldigestion of protein & carbohydrate Steatorrhea in advanced cases Weight loss & malnutrition due to food avoidance Reduction in insulin & glucagon secretions, resulting in diabetes Medical nutrition therapy –Dietary supplements to correct nutrient deficiencies –Avoidance of all alcohol –Pancreatic enzyme replacement

Nutrition & Diet Therapy (7 th Edition) Disorders of the Pancreas cont’d Cystic fibrosis –Genetic disorder characterized by abnormally thick exocrine secretions; often leads to respiratory illness & pancreatic insufficiency –Consequences Major complications: involve lungs, pancreas, sweat glands Persistent respiratory infections, causing inflammation of bronchial tissues & progressive airway obstruction Accumulation of digestive enzymes in pancreas due to thick pancreatic secretions that obstruct pancreatic ducts Malabsorption of protein, fat & fat-soluble vitamins Excessive loss of salt in sweat, increasing dehydration Chronic undernourishment, poor growth, difficulty maintaining body weight Pancreatitis, Hyperglycemia & diabetes

Nutrition & Diet Therapy (7 th Edition) Cystic fibrosis (con’t) –Medical nutrition therapy Increased energy intake (children may need % of recommended energy intake for normal growth & nutrition status) High-kcalorie & high-fat foods Frequent meals & snacks Supplement meals with milk shakes or liquid dietary supplements Supplemental tube feedings if energy intake is inadequate Pancreatic enzyme replacement at every meal or snack Multivitamin & fat-soluble vitamin supplements Liberal use of table salt & salty foods

Nutrition & Diet Therapy (7 th Edition) IV. Disorders of the Small Intestine Malabsorption common consequence when intestinal mucosa damaged due to inflammation or infection Celiac disease –Abnormal immune response to wheat gluten, causing severe intestinal damage & nutrient malabsorption –Also referred to as gluten-sensitive enteropathy or celiac sprue –Symptoms: GI disturbances such as diarrhea, steatorrhea & flatulence; symptoms exacerbated by milk products

Comparison of Villi Healthy Intestine-VilliCeliac Intestine-Villi Nutrition & Diet Therapy (7 th Edition)

Celiac disease (con’t) –Consequences Immune reaction to gluten causing changes in intestinal tissue –Reduction in mucosal surface area & digestive enzymes –May be restricted to duodenum or involve entire small intestine Malabsorption of all nutrients, especially macronutrients, fat-soluble vitamins, electrolytes, calcium, magnesium, zinc, iron, folate, vitamin B 12 Stunted growth in children, severe underweight Iron-deficiency anemia Low bone mineral density

Nutrition & Diet Therapy (7 th Edition) Celiac disease (con’t) –Medical nutrition therapy Life-long adherence to gluten-free diet Symptom relief usually evident within weeks, but mucosal healing may take years Avoidance of lactose- containing foods if lactose intolerant Dietary supplements Gluten-free diet Elimination of foods containing wheat, rye, barley Careful review of all ingredients on food labels (even small amounts of gluten can aggravate symptoms) Use of gluten-free products

Nutrition & Diet Therapy (7 th Edition) MNT for Celiac Disease

Nutrition & Diet Therapy (7 th Edition)

Disorders of the S.I. cont’d Short-bowel syndrome –Malabsorption syndrome that follows resection of small intestine, causing insufficient absorptive capacity in remaining intestine –Surgical resection of major portion of small intestine (treatment of Crohn’s disease, small intestinal cancers, other intestinal disorders) –Results in fluid & electrolyte imbalances, multiple nutrient deficiencies –Symptoms: diarrhea, steatorrhea, dehydration, weight loss, growth impairment (in children)

Nutrition & Diet Therapy (7 th Edition)

Short-bowel syndrome (con’t) –Intestinal adaptation: process of intestinal recovery, after resection, leading to improved absorptive capacity –Ileum has greater adaptive capacity than jejunum Permanent effects on vitamin B 12 nutrition & bile acid reabsorption if ileum removed—worsens fat malabsorption & diarrhea Removal of sphincter between ileum & cecum may result in infiltration of colonic bacteria into small intestine, causing bacterial overgrowth

Nutrition & Diet Therapy (7 th Edition) Short-bowel syndrome (con’t) –Medical nutrition therapy Immediately after surgery: fluid & electrolyte replacement (intravenous) First weeks: rehydration of diarrheal fluid losses Total parenteral nutrition, gradually reduced as oral feeding resumes Introduction of oral feedings as soon as possible to promote intestinal adaptation –Sips of liquid formulas, progressing to larger amounts –Solid foods, as tolerated –Small, frequent feedings –Low-fat, high-carbohydrate diet, if steatorrhea –Vitamin & mineral supplements –Low-oxalate diet to reduce risk of kidney stone development

Nutrition & Diet Therapy (7 th Edition) Nutrition in Practice— Anemia in Illness Anemia: condition of having too few red blood cells –Frequently first sign of another illness –May be reason for seeking medical attention –Develops when red blood cells (erythrocytes) are not produced in sufficient quantity, destroyed too quickly, lost due to bleeding –Red blood cells contain hemoglobin that carries oxygen to tissues –Produced in bone marrow (erythropoiesis) –Causes: Blood loss, malabsorption, chronic illnesses, medications

Nutrition & Diet Therapy (7 th Edition) Red Blood Cell Production

Nutrition & Diet Therapy (7 th Edition) NutrientActionsResult of Deficiency IronRequired for hemoglobin production Microcytic anemia: small, hypochromic cells Vitamin B 12 & Folate Maintains cell membrane integrity Macrocytic anemia: large, immature cells Vitamin ERole in hemoglobin production Hemolytic anemia: RBC breakdown Vitamin B 6 Role in hemoglobin production Microcytic anemia Vitamin CSupports blood vessel integrity Fragile, bleeding capillaries Protein Energy Malnutrition Protein synthesis needed for RBC development Anemia Nutrient Deficiencies & Anemia