Download - Nutrition & Diet Therapy (7 th Edition) Fiber-Modified Diets for Lower GI Tract Disorders Chapter 18
Nutrition & Diet Therapy (7th Edition)
Fiber-Modified Diets forLower GI Tract Disorders
Chapter 18
Nutrition & Diet Therapy (7th Edition)
I. Modifying Fiber Intake• Modification may require either increase or
decrease in dietary fiber; RDI is 38 g/day– Insoluble fibers: increase fecal weight & promote rapid
passage of wastes through large intestine (aka dietary fiber, found in whole grains)
– Soluble fibers: more viscous; slow passage of food– Health recommendation: most people should increase
fiber intake by increasing consumption of whole grains– Side effects of high-fiber diet: increased intestinal gas
(flatulence)—should be added gradually & portions increased as tolerance improves
Diets high in soluble fibers can lower
blood cholesterol levels
Nutrition & Diet Therapy (7th Edition)
Nutrition & Diet Therapy (7th Edition)
II. Disorders of Bowel Function
• Constipation– Difficulty passing stools (straining) or
infrequent bowel movements; often diagnosed when individual has fewer than 3 bowel movements/week
– Causes:• Food intake & activity-related causes: low fiber &/or
food intake, inactivity• Medical & neurological conditions: diabetes mellitus,
chronic renal failure, hypothyroidism, Parkinson’s disease, spinal cord injury, multiple sclerosis
• Pregnancy• Some medications & dietary supplements
Nutrition & Diet Therapy (7th Edition)
Disorders of Bowel (cont’d)
• Constipation (con’t)– Treatment
• Gradual increase in fiber intake, especially– Wheat bran– Fruits & vegetables – Fiber supplements
• Adequate fluid intake• Foods with mild laxative effects: prunes & prune juice• Laxatives, enemas & suppositories• Medical treatment
– Medications to increase peristalsis– Surgical intervention (colon resection, colostomy) as
last resort
Nutrition & Diet Therapy (7th Edition)
Disorders of Bowel (cont’d)• Diarrhea
– Passage of frequent, watery stools– Severe or persistent diarrhea can cause dehydration
& electrolyte imbalance– Causes
• Complication of medical problems• Infection, medications, dietary substances
– Treatment• Correction of underlying medical disorder• Change in medication or omission of offending
foods• Bulk-forming agents to reduce liquidity of stool• Antidiarrheal drugs for chronic diarrhea• Parenteral nutrition for severe, intractable
diarrhea
Nutrition & Diet Therapy (7th Edition)
Disorders of Bowel (cont’d)• Diarrhea (con’t)
– Nutrition therapy• Depends on cause, severity & duration of
diarrhea & degree of fluid loss• Rehydration therapy: replacement of fluid &
electrolytes for severe diarrhea• Fiber restriction for some individuals• Foods & beverages containing fructose, sugar
alcohols & lactose may aggravate symptoms• Avoidance of caffeine-containing products
– Rehydration therapy• The replacement of fluids and electrolytes
(water, salts, and glucose or sucrose) if diarrhea is severe.
Nutrition & Diet Therapy (7th Edition)
Nutrition & Diet Therapy (7th Edition)
Disorders of Bowel (cont’d)• Irritable bowel syndrome
– Characterized by chronic, recurrent & unexplainable intestinal symptoms
– Symptoms• Both diarrhea & constipation• Flatulence, bloating, distention• Mild to severe, often interfering in routine daily activities• Individuals may eventually become asymptomatic
– Possible Causes: May be associated with colonic response to meals, GI hormones & stress
– Treatment• Dietary adjustments• Stress management & behavioral therapies• Medications for management of symptoms
Nutrition & Diet Therapy (7th Edition)
Disorders of Bowel (cont’d)
• Irritable bowel syndrome (con’t)– Medical nutrition therapy
• Complete diet history to reveal behaviors that improve or worsen symptoms
• Dietary changes that help one symptom may aggravate another
• Increase fiber intake to reduce constipation & improve stool bulk
• Bulking agent• Avoidance of milk products (if lactose intolerant)• Caffeine & alcohol can exacerbate symptoms• Small, frequent meals• Possible low fat diet
Nutrition & Diet Therapy (7th Edition)
III. Inflammatory Bowel Diseases (IBD)
• Crohn’s disease– Involves small intestine & may result in
nutrient malabsorption– Complications
• Can occur in any region of GI tract—usually affects ileum &/or colon
• Deep inflammation, ulcerations, fissures & fistulas• Intestinal obstruction, intestinal cancers• Malnutrition• Malabsorption of fat, fat-soluble vitamins, calcium,
magnesium, zinc• Vitamin B12 deficiency, anemia
Nutrition & Diet Therapy (7th Edition)
Inflammatory Bowel Diseases (cont’d)
• Ulcerative colitis– Affects colon; always involves rectum & may
extend into additional segments of colon– Complications
• Tissue erosion or ulceration (primarily affecting mucosa & submucosa)
• Mild disease results in few complications, unless colon involved
• Weight loss, fever, weakness• Anemia• Dehydration & electrolyte imbalance• Protein loss
Nutrition & Diet Therapy (7th Edition)
• In Crohn’s, the mucosa has a “cobblestone” appearance due to deep fissuring in the inflamed mucosal tissue
• In UC, the colon appears inflamed and reddened, and ulcers are visible
Nutrition & Diet Therapy (7th Edition)
Nutrition & Diet Therapy (7th Edition)
Treatment of InflammatoryBowel Diseases
• Drug treatment– Medications to control symptoms: reduce
inflammation & minimize complications• Antidiarrheal agents• Immunosuppressants• Anti-inflammatory drugs
– Help to achieve remission but associated with side effects (diet-drug interactions) detrimental to nutrition status
Nutrition & Diet Therapy (7th Edition)
Inflammatory Bowel Diseases
• Medical Nutrition Therapy– Crohn’s disease:
aggressive dietary management
– Manage symptoms & complications
• High-kcalorie, high-protein• Liquid supplements• Restriction of fiber &
lactose• Vitamin & mineral
supplements
– Ulcerative colitis: requires little dietary adjustment
– In severe illness, manage symptoms & complications
• Restoration of fluid & electrolytes (possible intravenous replacement)
• Correct deficiencies resulting from protein & blood losses
• Low-fiber diet• Bowel rest (withhold foods)• Parenteral nutrition support
Nutrition & Diet Therapy (7th Edition)
IV. Diverticular Disease of the Colon
• Diverticulosis: presence of pebble-size outpockets in intestinal wall (diverticula)– Incidence increases
with age– May remain symptom-
free until complication develops
– Increased fiber in diet (increased stool weight & bulk) may decrease development
• Diverticulitis: inflammation or infection developing around a diverticulum– Common complication of
diverticulosis– Spread of infection to
adjacent organs may result in development of fistula
– Infection may spread to peritoneal cavity (rare occurrence)
– Symptoms: persistent abdominal pain, fever, alternating constipation & diarrhea
Nutrition & Diet Therapy (7th Edition)
Nutrition & Diet Therapy (7th Edition)
Treatment for Diverticular Disease
• Focuses on symptom relief– Reducing pain– Alleviating constipation– Increasing fiber to prevent disease progression
• Add wheat bran to meals• Use bulk-forming agents• Some recommend avoidance of nuts, popcorn & foods
containing seeds—no evidence that this will reduce complications
– Antibiotics to treat infection– Clear liquid diet, progressed to solid foods as tolerated– Bowel rest when necessary; intravenous fluid treatment– Surgical intervention to treat complications, including
removal of colon
Nutrition & Diet Therapy (7th Edition)
V. Colostomies & Ileostomies
• Ostomy: surgically created opening (stoma) in abdominal wall for elimination of dietary waste; may be permanent or temporary– Colostomy: creation of stoma from section of colon– Ileostomy: creation of stoma from section of ileum– Dietary waste collected in disposable bag affixed to skin
surrounding stoma; or interior pouch may be surgically constructed behind stoma
– Stool consistency varies according to functional capacity of remaining length of colon
• Removal of small portion of colon: stools may continue to be semi-solid
• Removal or bypass of entire colon: absorption of fluid & electrolytes reduced substantially, resulting in liquid stool
Nutrition & Diet Therapy (7th Edition)
Nutrition & Diet Therapy (7th Edition)
Nutrition Therapy for Ostomies
• Gradual progression of diet following surgery– Clear liquids, low in sugars, progressing to low-fiber diet as
tolerated– Small, frequent meals better tolerated initially– Addition of questionable foods slowly & one at a time
• Colostomy– Dietary concerns depend on length of colon removed– High-fiber diet to improve stool consistency & promote regularity– Removal of large segment: recommendations may be same as
ileostomy• Ileostomy
– Chew thoroughly to ensure adequate digestion & to prevent obstruction
– Avoidance of insoluble fibers—reduce intestinal transit time & may increase output
– Inclusion of at least 8 cups of liquid/day
Nutrition & Diet Therapy (7th Edition)
Nutrition Therapy for Ostomies
Obstructions• A primary concern of ileostomy
patients• Cut food into small pieces,
carefully chew• Foods that may cause problems
– Corn– Celery– Coconut– Dried fruit– Grapes– Nuts & popcorn– Raw cabbage– Unpeeled apples
Reducing gas & odors• A concern for all ostomy patients• Avoid foods that are gas-
producing• Avoid foods that produce odors
– Fish– Eggs– Dried beans & peas– Onions & garlic– Asparagus & Brussels sprouts– Beer
• Avoid practices that increase gas production
– Smoking– Gum or tobacco chewing– Use of drinking straws– Eating quickly
Nutrition & Diet Therapy (7th Edition)
Nutrition & Diet Therapy (7th Edition)
Nutrition in Practice—Probiotics & Intestinal Health
• Shortly after birth, GI tract is colonized with wide variety of bacteria (flora)– Majority reside in colon– Populations vary within different regions of GI
tract– Benefits to health
• Degrade undigested or unabsorbed dietary carbohydrate, including fibers resistant to digestion
• Stimulate immune defenses to prevent overgrowth of pathogenic bacteria
Nutrition & Diet Therapy (7th Edition)
Probiotics• Foods & supplements
supplying live, nonpathogenic bacteria in sufficient numbers to benefit health
• Resistant to destruction by stomach acid, bile, other digestive substances
• Alter intestinal environment to benefit human host
• Possible help for medical problems: - May prevent & treat some gastric & intestinal disorders
– Improve lactose digestion– Improve availability &
digestibility of various nutrients
– Alter susceptibility to food allergens & alleviate some allergy symptoms
– Help prevent or reverse infections in urethra & vagina
• Benefits to health not conclusive in research— therefore should be considered adjuncts to primary medical treatment for illness
Nutrition & Diet Therapy (7th Edition)
Probiotics
• Intestinal disorders helped by probiotics– Shortened duration of diarrhea caused by
rotavirus in infants & children– Decreased incidence of traveler’s diarrhea in
tourists visiting high-risk areas– Prevent recurrence of infectious diarrhea in
hospitalized patients– Reduced incidence & duration of antibiotic-
associated diarrhea in infants & children– Reduced occurrence of pouchitis (inflammation of
surgical pouch created in patients with ileostomy or colostomy)
Nutrition & Diet Therapy (7th Edition)
Probiotics• Sources of probiotic bacteria
– Foods—provided mainly by fermented foods• In U.S.—yogurt & acidophilus milk (produced using
species of Lactobacilli & Bifidobacteria)• In Europe & Asia—yogurt, milk, ice cream, oatmeal
gruel, soft drinks– Dietary supplements– Prebiotics in foods that may stimulate growth in large
intestine• Safety
– Infection in immune-compromised individuals– Lack of industry standards for probiotics in foods &
supplements