Diverticulosis is a condition characterized by small pouches (diverticula) that form and push outward through weak spots in the large intestine. Once diverticula have formed, there is no way to reverse the process. When diverticula become infected, the condition is called diverticulitis. Most people with diverticulosis do not experience symptoms. As for diverticulitis, the most common symptom is abdominal pain with tenderness around the left side of the lower abdomen. Fever, nausea, vomiting, chills, cramping, and constipation may occur as well. Diverticular disease is common in industrialized countries, especially in the United States, Canada, the United Kingdom, and Australia, and fairly rare in Asia and Africa. It affects about 50% of Americans by age 60 and nearly all by age 80. A low-fiber diet is believed to be the main cause of the disease. It was first described in the United States in the early 1900s, at the time when processed foods were introduced into the American diet and many of these foods contain refined flour. Unlike whole-wheat flour, refined flour has no wheat bran and is accordingly a low-fiber food. The prevalence of the disease in industrialized countries seems to confirm the connection of diverticular disease with a low-fiber diet, since it occurs rarely in Asia or Africa, where people eat high-fiber, vegetable-based diets.

Description

It has been shown that increasing the amount of fiber in the diet may reduce symptoms of diverticular disease. The American Dietetic Association recommends a daily intake of 20–35 grams of fiber. A diverticular disease diet will accordingly seek to increase dietary fiber to these levels to prevent constipation and the undue colon pressure that causes diverticula.

Examples of foods that contain fiber and can be part of a diverticular disease diet include (amounts of fiber shown for a medium fruit or 1 cup of vegetable, fruit or grain):

Apple, raw, with skin (3.3g)
Peach, raw (1.5g)
Pear, raw (5.1g)
Pineapple (1.9g)
Tangerine, raw (1.9g)
Blueberries (4.0g)
Cranberries (4.0g)
Raspberries (8.3g)
Asparagus, 4 spears, fresh, cooked (1.2g)
Broccoli, fresh, cooked (5.2g)
Brussels sprouts, fresh, cooked (4g)
Cabbage, fresh, cooked (3g)
Carrot, fresh, cooked (4.6g)
Cauliflower, fresh, cooked (3.4g)
Celery, raw (2.1g)
Romaine lettuce (1.2g)
Spinach, fresh, cooked (4.4g)
Summer squash, cooked (2.5g)
Tomato, raw (1g)
Winter squash, cooked (5.7g)
Baked beans, canned, plain (12.6g)
Kidney beans, fresh, cooked (11.4g)
Lima beans, fresh, cooked (13.2g)
Potato, fresh, cooked (2.3g)
Bread, whole-wheat, 1 slice (1.9g)
Brown rice, cooked (3.5g)
Cereal, bran flake (7.1g)
Oatmeal, plain, cooked (4g)
White rice, cooked (0.6g)

There are several types of dietary fiber, which makes it easy to include it in the diet:

Cellulose. Found in bran, legumes, peas, root vegetables, the cabbage family, the outer covering of seeds, and most fruits
Hemicellulose. A major constituent of cereal fiber, found in bran and whole grains
Polyfructoses. Examples are inulins and oligofruc-tans, found in onions, garlic, artichokes, soybean
Gums. These are substances secreted by a plant at injury sites. They are composed of various sugars and sugar derivatives. Found oatmeal, barley, and legumes
Mucilages. Gelatinous substances found in most plants
Pectins. Water-soluble and gel-forming substances found in apples, strawberries, and citrus fruits
Lignin. This is the primary noncarbohydrate component of fiber. It is highest in mature root vegetables like carrots or fruits with edible seeds like strawberries
Resistant starches. These are starches that are classified as fibers because they are not digested by the body. They are found in whole legumes, potatoes and bananas and plantains

To help increase dietary fiber in the diet, breakfast should include a bowl of porridge made with millet, oats or brown rice, toast made with whole-grain bread instead of white bread, whole-grain ready-to-eat cereals with milk, and a bowl of fruit instead of fruit juice. During the day, snacks can include fresh fruit, or dried fruits like raisins, prunes, dates, apricots, or a few wholegrain crackers. In meals, brown rice should replace white rice. Pasta dishes should include more vegetables and fruit? to increase the fiber content of the meal. Serve fruit after meals instead of a dessert. Vegetables should also be eaten at each meal. Sandwiches should be made with whole-grain bread and include vegetables.

Besides adding fiber foods to a diverticular disease diet, the health practitioner may also prescribe a fiber supplement such as Citrucel or Metamucil once a day. These products supply 2-3.5g of fiber per tablespoon, mixed with 8 ounces of water Some physicians also recommend to avoid nuts, popcorn, and sunflower, pumpkin, caraway, and sesame seeds as they believe that particles of these foods could enter, block, or.

KEY TERMS

Abdomen —Part of the body that extends from the chest to the groin.

Abdominal cavity —The hollow part of the body that extends from the chest to the groin. It is located between the diaphragm, which is the thin muscle below the lungs and heart, and the pelvis, the basin-shaped cavity that contains the reproductive organs, bladder, and rectum. The abdominal cavity contains the abdominal organs.

Bile —Digestive juice secreted by the liver and stored in the gallbladder; helps in the digestion of fats.

Colon —Part of the large intestine, located in the abdominal cavity. It consists of the ascending colon, the transverse colon, the descending colon, and the sigmoid colon.

Diverticulitis —Inflammation of the small pouches (diverticula) that can form in the weakened muscular wall of the large intestine.

Feces —Waste product of digestion formed in the large intestine. About 75% of its mass is water, the remainder is protein, fat, undigested roughage, dried digestive juices, dead cells, and bacteria.

Gastrointestinal tract (GI tract) —The tube connecting and including the organs and paths responsible for processing food in the body. These are the mouth, the esophagus, the stomach, the liver, the gallbladder, the pancreas, the small intestine, the large intestine, and the rectum.

Immune system —The integrated body system of organs, tissues, cells, and cell products such as antibodies that protects the body from foreign organisms or substances.

Inflammation —A response of body tissues to injury or irritation characterized by pain and swelling and redness and heat.

Insoluble —That cannot be dissolved. Insulin—A hormone secreted by the pancreas and required for the regulation of the metabolism of carbohydrates and fats.

Intestinal flora —The sum of all bacteria and fungi that live in the intestines. It is required to break down nutrients, fight off pathogens and helps the body build the vitamin E and K. An unbalanced intestinal flora can lead to many health problems.

Inulin —Naturally occurring oligosaccharides (several simple sugars linked together) produced by many types of plants. They belong to a class of carbohydrates known as fructans.

Large intestine —The terminal part of the digestive system, site of water recycling, nutrient absorption, and waste processing located in the abdominal cavity. It consists of the caecum, the colon, and the rectum.

Mucilage —A sticky substance used as an adhesive. A gummy substance obtained from certain plants.

Nutrient —A chemical compound (such as protein, fat, carbohydrate, vitamins, or minerals) that make up foods. These compounds are used by the body to function and grow.

Soluble —Capable of being dissolved.

Syndrome X —A group of risk factors that together, put someone at higher risk of coronary artery disease. These risk factors include: central obesity (excessive fat tissue in the abdominal region), glucose intolerance, high triglycerides and low HDL cholesterol, and high blood pressure.

irritate the diverticula. However, no scientific evidence support this opinion. The seeds in tomatoes, zucchini, cucumbers, strawberries, and raspberries, as well as poppy seeds, are generally considered harmless. An eating plan for diverticular disease is usually based on what works best for each person. To help the colon rest, the treating physician may also recommend bed rest and a liquid diet.

Function

Fiber is the edible part of fruits, vegetables, and grains that the body cannot digest. Since they are not absorbed into the body, dietary fibers are not considered a nutrient. Some fiber dissolves easily in water and becomes soft in the intestines, while insoluble fiber passes almost unchanged through the intestines. Both kinds of fiber are required to make stools soft and easy to pass. Fiber also prevents constipation, which makes the bowel muscles strain to move stool that is too hard. It is believed to be the main cause of increased pressure in the colon that may cause the weak colon spots to bulge out and become diverticula.

Many plant foods contain both soluble and insoluble fibers. For example, psyllium husks, contain a mixture of 70% soluble and 30% insoluble fibers. Despite the general use of the terms “soluble’ and “insoluble’ to describe the health benefits of dietary fiber, many nutrition experts are now using the terms “viscous’ and “fermentable’ to describe the functions and health benefits of dietary fiber. These include:

Reducing blood cholesterol levels: Viscous fibers lower cholesterol levels by reducing the absorption of dietary cholesterol. In addition, they combine with bile acids. These are compounds produced by the liver from cholesterol that are required for the breakdown of fats. After combining with bile acids, the compounds are removed from circulation and do not make it back to the liver. As a result, the liver must use additional cholesterol to manufacture new bile acids. Soluble fiber may also reduce the amount of cholesterol manufactured by the liver.
Normalizing blood sugar levels: Viscous fibers are also involved in controlling blood glucose levels because they slow down the rate at which food leaves the stomach and delay the absorption of glucose after a meal. Viscous fibers also increase insulin sensitivity. As a result, viscous fibers are believed to play a role in the prevention and treatment of type 2 diabetes.
Supporting bowel regularity: Fermentable fibers are fermented by the intestinal flora, the bacteria and fungi that live in the intestines. The fermentation of dietary fiber in the large intestine produces a short-chain fatty acid called butyric acid, which is used as fuel by the cells of the large intestine and helps maintain the health of the colon. Fermentable fibers also help maintain healthy populations of bacteria in the intestinal flora. Fibers that are not fermentable help maintain bowel regularity by increasing the bulk of the feces and decreasing the time required by fecal matter to move through the intestines.

Benefits

Fiber keeps stool soft and lowers pressure inside the colon so that bowel contents can move through easily. This is why it is considered beneficial for diverticular disease. Eating a high-fiber diet will not only treat diverticular disease, it is also believed to play a role in the prevention and treatment of the following health conditions:

breast cancer
cardiovascular disease
colon cancer
diabetes
gallstones
high cholesterol
irritable bowel syndrome
obesity
syndrome X

Precautions

When increasing the fiber content of the diet, it is recommended to add fiber progressively, adding just a few grams at a time to allow the intestinal tract to adjust. Otherwise, abdominal cramps, gas, bloating, and diarrhea or constipation may result. Intake of dietary fiber exceeding of 50g per day may also lead to intestinal obstruction. Excessive intake of fiber can also cause a fluid imbalance, leading to dehydration This is why people who start increasing their fiber intake are often advised to also increase their water intake. Excessive intake of dietary fiber has been linked with reduced absorption of vitamins, minerals, proteins, and calories. However, it is unlikely that healthy people who consume fiber in amounts within the recommended ranges will have problems with nutrient absorption.

Parents are urged to use caution when adding extra fiber to their child’s diet. Excessive amounts of high-fiber foods may cause a child to fill up quickly, reducing appetite and possibly depriving the child of needed nutrients from a well-balanced diet. Elderly people and those who have had gastrointestinal surgery should also exercise caution when increasing their dietary fiber intake.

Risks

Most people recover fully after treatment for diverticular disease. If not treated however, diverticulitis can lead to the following serious conditions:

Intestinal perforation: The diverticula burst because of increased pressure within the intestine
Peritonitis: This is a serious infection of the abdominal cavity outside the intestine. It often occurs after perforation, when the contents of the intestine are leaked into the abdominal cavity
Abscess formation: Sacs of infected intestinal material and pus can form that are very difficult to cure
Fistula formation: An abnormal connection between the colon and another organ can form. This occurs when the colon, damaged by infection, comes in contact with other tissue, such as the bladder, the small intestine, or the inside of the abdominal wall, and sticks to it. Fecal material from the colon can then get into the other tissue
Blockage of the intestine: This can result from hard fecal matter reaching out of diverticula
Bleeding in the intestine: Stool that is trapped in a diverticulum may cause bleeding

QUESTIONS TO ASK YOUR DOCTOR

What are diverticulosis and diverticulitis?
How serious is this condition?
What are the possible complications?
What causes diverticular disease?
What is the treatment for diverticular disease?
Will tests be required?
Will surgery be necessary?
Are there foods that should be avoided?
Are there foods that are recommended?
How can I tell if I am getting enough fiber in my diet?
How will I know if I am getting too much fiber in my diet?
Would seeing a dietician for an eating plan help?
How effective is diet in controlling this disease?
Is there a cure for diverticular disease?
What is the function of dietary fiber?
Do you recommend intestinal cleansing?
What are some simple steps for increasing the fiber intake of my meals?
Should I eat one type of fiber more than another?

Research and general acceptance

Most health practitioners agree that the lack of fiber and bulk in the diet is the major cause of diverticular disease. As foods are becoming more highly refined, more people are suffering from diverticular disease symptoms. Eating a high-fiber diet is accordingly the only requirement highly emphasized by the medical profession. Eliminating specific foods is not considered necessary as no research supports that it may improve the condition. A gradual switch to a diet with increased intake of soluble fiber (green vegetables, oat bran) usually leads to an improvement in bowel function. There is general agreement on food sources being more efficient fiber sources than supplements since they also supply additional nutrients. Excessive use of fiber supplements can also lead to acute digestive problems and blockages.

In its most recent 2005 public health recommendations for dietary fiber, the National Academy of Sciences established an Adequate Intake (AI) level of 38g of total daily fiber for males 19–50 years of age and 25g for women in this same age range. The report also states that individuals in this age range in the United States only get about half this much fiber each day. The recommendation for children older than 2 years is to increase dietary fiber intake to an amount equal to or greater than their age plus 5 g/day. There are currently no published studies that indicate optimal dietary fiber intakes for infants and children under 2 years of age. Until more information becomes available, a sensible guideline is to introduce a variety of fruits, vegetables, and easily digested cereals after weaning.

It is understood that, as the body ages, the outer layer of the intestinal wall thickens, which narrows the intestine. As a result, stool moves more slowly through the colon, increasing the pressure. Hard stools, such as those produced by a diet low in fiber, can further increase pressure. Repeated straining during bowel movements also increases pressure and contributes to formation of diverticula. As for the cause of diverticulitis, there is broad agreement that it occurs when diverticula become infected or inflamed, but medical experts are not know precisely what causes the infection. It is believed to start when stool or bacteria are caught in the diverticula.

The United States Food and Drug Administration (FDA) has approved the following claims about dietary fiber that can be listed on food labels:

Good Source of Fiber, Contains Fiber or Provides Fiber: Any food product that contains 2.5 to less than 5g of fiber per serving (less than 20% of the daily value of dietary fiber) and is low in total fat per serving (3g or less fat per serving).
High Fiber, Rich in Fiber, Excellent Source of Fiber: Any food product that contains at least 5g or more of dietary fiber per serving (20% or more of the fiber daily value) and is low in total fat per serving (3g or less fat per serving).

Resources

BOOKS

Black, P., Hyde, C. Diverticular Disease New York, NY: John Wiley & Sons, 2005.

Brumback, R. A., Brumback, M. H. The Dietary Fiber Weight Control Handbook Charleston, SC: BookSurge Publishing, 2006.

McClelland, J., Smith, A. How to Cope Sucessfully with Diverticulitis Farnham, UK: Wellhouse Publishing Ltd, 2001.

Miskovitz, P., Betancourt, M. The Doctor’s Guide to Gastrointestinal Health: Preventing and Treating Acid Reflux, Ulcers, Irritable Bowel Syndrome, Diverticulitis, Celiac Disease, Colon Cancer, Pancreatitis, Cirrhosis, Hernias and more New York, NY: Wiley, 2005.

Parker, J. N, ed. The Official Patient’s Sourcebook on Diverticular Disease San Diego, CA: Icon Health Publications, 2002.

Trickett, S. Irritable Bowel Syndrome and Diverticulitis: A Self-Help Plan New York, NY: Thorsons (Harpercollins), 2002.

White, A. Diverticulitis: Safe Alternatives Without Drugs New York, NY: Thorsons (Harpercollins), 1998.

Wood, G. K. The Complete Guide to Digestive Health: Plain Answers About IBS, Constipation, Diarrhea, Heartburn, Ulcers, and More Peachtree City, GA: FC&A Publishing, 2006.