Constipation and diverticular disease can be considered twin scourges of today's refined diet. While relatively rare in many parts of the world, diverticular disease is common in countries such as the United States, England, and Australia where diets tend to be low in fiber. In fact, diverticular disease was first noticed in the United States at about the same time processed foods were introduced.

Both constipation and diverticular disease are also quite common among older adults. People who are 65 and older often complain about constipation. And doctors estimate that about half of all Americans over age 60 and nearly all of those over 80, have some degree of diverticulosis - the presence of small pouches (diverticula) that bulge outward through weak patches in the wall of the large intestine, also known as the colon.

Causes of constipation

Constipation is defined as passage of small amounts of hard, dry stool less than four times a week. The most common causes are diets low in fiber and fluid, and lack of exercise. Other causes include certain medications and ignoring the natural urge to have a bowel movement. Perceived problems with the frequency of bowel movements should be discussed with your doctor, as should any sudden changes in bowel habits. The use of laxatives, too, should be discussed with your physician, since they can be both unnecessary and habit-forming.

The constipation-diverticulosis link

Because straining to move stool through the intestinal tract puts pressure on the walls of the intestine, chronic constipation can be a major contributor to the formation of diverticula. Aging, too, increases the likelihood of developing these pea-sized pouches.

Diverticulosis often causes no discomfort or symptoms. In fact, most people are unaware that they have diverticula. About 20% of the time, however, one of the pouches can become infected or inflamed, causing acute symptoms such as abdominal pain, fever, and nausea. This condition is known as diverticulitis, and requires medical attention.

Bulking up on fiber

Consuming a fiber-rich diet is a natural way to combat both constipation and diverticulosis. Fiber is the undigested part of food, which adds bulk to stools and acts like a sponge to draw in water. These effects soften stools and cause less straining. This may also help prevent diverticulosis from progressing to the more serious diverticulitis.

Despite the health benefits of high-fiber diets, many people consume too little. The American Dietetic Association recommends that people consume 20 to 35 grams of fiber a day. This represents a 10-50% increase over the 12 to 17 grams of fiber that the average American eats or drinks on a daily basis.

All fruits, vegetables, dried beans, and nuts contain fiber, as do bran and whole-grain foods like whole-wheat bread, whole-grain cereals, brown rice, and oatmeal. Emphasizing these foods over more refined products can help keep you «regular». If you enjoy snacks, try replacing a sweet snack with a slice of whole-wheat toast and jam, or some dried apricots or figs; for a savory snack try whole-wheat crackers and peanut butter. Popcorn is another good choice.

Historically, people with diverticular disease have been warned to avoid foods with small seeds such as tomatoes or berries, because it was believed these could lodge in the diverticula and cause inflammation. According to the National Institutes of Health, however, this is a controversial point and «no evidence supports this recommendation.» If you've been diagnosed with diverticular disease, you may wish to discuss with your doctor whether or not you should eliminate any particular foods from your diet.

Increase fiber intake slowly

Note that fiber should be added to the diet slowly, over a period of weeks, to allow your body to adjust to the increase. Also make sure to include at least eight cups of fluid a day so that your intestine has plenty to draw on as fiber passes through.

Adding fiber to your diet doesn't mean you need to look for special high-fiber foods. Consider that over the course of a day, eating the following simple, familiar foods provides enough fiber to meet the needs of most people:

• one bowl of oatmeal with dried apricots
• one banana
• two slices of whole wheat bread
• one pear
• one small baked potato with the skin
• ½ cup of peas
• one handful of whole wheat crackers