Dietary fibers and related diseases

Contents

1. Introduction
2. High fiber diet and related diseases
3. Low fiber diet and related diseases
4. Other related topics

Introduction to Dietary fibers

Although the importance of dietary fibers was recognized only a few decades ago, throughout the history a few perceptible individuals have from time to time drawn attention to the need for fiber in the diet. Hippocrates commented on the laxative effect of coarse flour.

High fiber diet has a positive effect on following diseases

1. constipation
2. hemorrhoids
3. Anal fissure
4. irritable bowel disease
5. diverticular disease
6. High cholesterol
7. Diabetes
8. Obesity

High fiber diet has a negative/uncertain effect on following diseases

1. Colorectal cancers
2. Diverticular disease

Low fiber diet has a positive effect on following diseases

1. Coeliac disease
2. Pancreatic diseases
3. Vitamin deficiency diseases
4. Mineraldeficiency diseases

Low fiber diet has a negative/uncertain effect on following diseases

1. Fecal incontinence
2. Ileitis

Constipation and dietary fibers

Constipation can be defined as a bowel frequency of fewer than three motions per week or the need to strain more than 25% of the time during defecation. According to these criteria, bowel frequency is normal in 99% of the population. Most adults with an abnormally low bowel frequency are women.

Most of the time management depends on the underline cause but general management is the same irrespective of the cause Dietary fiber increases the weight and size of your stool and softens it. A bulky stool is easier to pass, decreasing your chance of constipation. If you have loose, watery stools, fiber may also help to solidify the stool because it absorbs water and adds bulk to stool.

Hemorrhoids (piles) and dietary fibers

Individuals with constipation tend to strain while defecating so they are more vulnerable to develop hemorrhoids. Therefore prevention of constipation is the mainstay of treatment. For that dietary modification are required as discussed in above.

Anal fissures and dietary fibers

The management of the acute fissure is conservative. Stool softeners for those with constipation, increased dietary fiber, topical anesthetics, glucocorticoids, and sitz baths are prescribed and will heal 60 to 90% of fissures. Chronic fissures are those present for >6 weeks. These can be treated with modalities aimed at decreasing the anal canal resting pressure including nitroglycerin ointment (0.2%), applied three times a day, and botulinum toxin type A, up to 20 units, injected into the internal sphincter on each side of the fissure. Surgical management includes anal dilation and lateral internal sphincterotomy.

Irritable bowel disease (IBD) and dietary fibers

There are two types of IBD’s; crohn’s disease and ulcerative colitis. Among those crohn’s disease needs a dietary modification. Patients should be advised to eat a well-balanced diet with high fiber content. A low-fat, lactose-free or low-residue

Diet is required in those with steatorrhoea, hypolactasia or stricture. Elemental diets (containing amino acids and glucose) and polymeric diets have been shown to be almost as effective as prednisolone in treating active disease and can be a useful form of therapy in some patients.

Diverticular disease and dietary fibers

The term ‘diverticulosis’ simply describes the presence of diverticula; no symptoms need be present. Diverticulitis is the clinical syndrome that occurs on the rare occasions when a diverticulum becomes inflamed; it may be associated with local perforation leading to pericolitis. Diverticular disease encompasses all manifestations, including the muscular abnormalities in the colonic wall that usually accompany diverticulosis.

A high-fibre diet and/or bulking agents (e.g. bran, ispaghula) are recommended in diverticulosis. The amount of bran required is determined by trial and error, starting with a small dose.

High cholesterol and dietary fibers

Soluble fiber found in beans, oats, flaxseed and oat bran may help lower total blood cholesterol levels by lowering low-density lipoprotein, or "bad," cholesterol levels.

Diabetes and dietary fibers

Fiber, particularly soluble fiber, can slow the absorption of sugar, which for people with diabetes; can help improve blood sugar levels. A high-fiber diet may also reduce the risk of developing type 2 diabetes.

Obesity and dietary fibers

High-fiber foods generally require more chewing time, which gives your body time to register when you're no longer hungry, so you're less likely to over eat. Also, a high-fiber diet tends to make a meal feel larger and linger longer, so you stay full for a greater amount of time. And high-fiber diets also tend to be less "energy dense," which means they have fewer calories for the same volume of food.

Colorectal cancers and dietary fibers

Evidence that dietary fiber reduces colorectal cancer is mixed — some studies show benefit, some show nothing and even some show greater risk. If you're concerned about preventing colorectal cancer, adopt or stick with a colon cancer screening regimen. Regular testing and removal of colon polyps can prevent colon cancer.

Pancreatic disease and dietary fibers

The effect of dietary fiber on pancreatic enzymes was examined in vitro, employing different concentrations of cellulose, pectin, and wheat bran incubated with amylase, lipase, and trypsin. Ingestion of a high fiber diet was associated with a small but significant (p less than 0.01) increase in fecal weight and fecal fat excretion. All patients complained of increased abdominal flatulence with high fiber diet, however, no significant increase in frequency of bowel movements was noted. In vitro studies demonstrated reduction in pancreatic enzyme activity by increasing concentration of dietary fiber and its components. These data suggest that steatorrhea may be enhanced with the ingestion of high fiber diet in patients with exocrine pancreatic insufficiency on oral pancreatic enzyme therapy. Increase in fecal fat excretion may, in part, be related to reduction in the activity of pancreatic enzymes by the dietary fiber.

Coeliac disease and dietary fibers

In coeliac disease, the mucosa of the small intestine is abnormal. The condition improves morphologically and symptomatically with a gluten-free diet treatment of coeliac disease requires a gluten-free diet avoiding wheat, rye and barley products. Debate continues about the possible toxicity of oats, but commercial oat flours may be contaminated with wheat and are therefore probably best avoided. The diet is low in fiber, so regular addition of rice bran and ispaghula husks may be useful.

Other related topics

1. What are the dietary fibers?
2. How does dietary fiber affect on nutrients absorption?
3. Bacterial flora and dietary fibers
4. Bile acids absorption and dietary fibers