Did you know that more than 41 million people visit the doctor each year with their chief complaint being some kind of gastrointestinal (GI) symptom (National Center for Health Statistics 2004)? Symptoms can range from the occasional, pesky stomach upset for some people to a life-threatening case of chronic diarrhea for those who suffer from a disorder like inflammatory bowel disease.

Not only can gastrointestinal ailments wreak havoc on the digestive tract, but they can also get in the way of exercise programs, meal plans and social interactions with family and friends. However, by making the right nutritional choices, people with gastrointestinal ailments can begin to take back their lives.

This article provides a brief introduction to the most common gastrointestinal ailments, such as irritable bowel syndrome, gastroesophageal reflux disease, lactose intolerance, celiac disease and inflammatory bowel disease. The symptoms and causes of each disorder will be discussed, as will nutritional recommendations you can suggest to your clients for optimal disease management. (See page 68 for an illustration of the digestive system.)

Irritable Bowel Syndrome

The most prevalent GI disorder is irritable bowel syndrome (IBS), a poorly understood disorder of the large intestine that causes recurrent abdominal pain, bloating, discomfort and changes in the frequency and consistency of bowel movements. Young women are most often the victims of IBS, although it can be diagnosed in both genders at any age.

What Causes It? While no one is exactly sure of the cause of IBS, many experts think the condition is a manifestation of a hypersensitive GI tract that is easily pained and stimulated; this stimulation causes excess bloating, gas and cramping after minor assaults, such as the physical burden of digesting a large and bulky meal.

What Are the Symptoms? IBS is called a syndrome rather than a disease because it is defined by a cluster of symptoms that typically occur in tandem. To be diagnosed as having IBS, a person must have had pain or discomfort for 12 weeks of the previous 12 months and must experience at least two of the following symptoms:

  • relief of pain with defecation
  • looser or more frequent stools
  • harder or less frequent stools

Symptoms often worsen in people with IBS after they have eaten large meals, taken certain medicines, become emotionally upset or ingested milk products, chocolate, alcohol, caffeine, carbonated drinks or fatty foods.

What’s the Best Diet Strategy? High-fiber foods like broccoli, apples and whole-grain breads can actually alleviate some of the symptoms of IBS by softening the stool and relieving constipation. Also, research suggests that probiotics—the live microbial organisms found in certain foodstuffs such as yogurt—may help people who suffer from IBS (Floch 2005). For many people with the syndrome, minimizing stress through regular exercise is an effective component of a treatment plan (National Institute of Diabetes and Digestive and Kidney Diseases [NIDDK] 2003; Talley & Spiller 2002).

Gastroesophageal Reflux Disease (GERD)

Gastroesophageal reflux disease (also known as heartburn) results from stomach acids being pushed up into the esophagus owing to relaxation of the sphincter that separates the esophagus from the highly acidic stomach contents.

What Causes It? No one knows exactly what causes the disorder, but people who are obese or smoke tend to be at greater risk of developing GERD. Typically, smoking, alcohol, coffee, chocolate, citrus fruits and fatty foods exacerbate heartburn.

What Are the Symptoms? Characteristic signs of GERD
include chest pain that worsens after lying down; difficulty swallowing; coughing and wheezing; and regurgitation of sour-
tasting food.

What’s the Best Diet Strategy? People who suffer from GERD should avoid alcohol, coffee, chocolate, citrus fruits and fatty foods. Engaging in regular exercise is also recommended, especially if the client is overweight or obese. Importantly, individuals with GERD should seek medical treatment promptly if they experience unexplained weight loss or have difficulty swallowing, or if the heartburn returns multiple times per week, is not relieved by over-the-counter antacids or causes them to wake up at night (Moayyedi & Talley 2006).

Lactose Intolerance

The enzyme lactase is required to break down foods that contain lactose, a sugar found mostly in milk, cheese, ice cream and other dairy products but also hidden in some processed food.

What Causes It? Up to 100% of Native Americans and Asians, as many as 80% of African Americans and Latinos and about 15% of Caucasians do not produce sufficient lactase (Swagerty, Walling & Klein 2002). When lactose is not properly broken down, water is drawn into the intestinal lumen, which leads to watery diarrhea. Another hallmark of lactose intolerance is the result of bacteria in the gut, which love to feast on sugar; the byproduct of this process is a buildup of gas, which causes excessive flatulence.

It should be noted that being lactose intolerant is not the same as being lactose allergic. People who are allergic to proteins in dairy products are at risk for developing much more severe symptoms as a result of the body’s mounting an overwhelming immune response to the offending allergen.

What Are the Symptoms? Overwhelmed by abdominal pain, bloating, excessive flatulence and watery stool, people with lactose intolerance can find life miserable—especially after eating a hefty, dairy-filled meal but even after downing a large glass of milk. The severity of the symptoms can vary, depending on the amount of lactose ingested and the individual’s age (symptoms are generally worse in older people).

What’s the Best Diet Strategy? Many people are lactose intolerant, but having the condition does not mean they should avoid all lactose-containing products. Rather, people are
encouraged to consume small amounts of dairy products up to the point at which symptoms would appear (this is usually equivalent to about 8–12 ounces of milk), because these products provide the vast majority of calcium intake for most people. A calcium supplement or lactose-reduced milk is a good choice to help people maintain optimal intake of the mineral (Montalto et al. 2006). Clients with lactose intolerance can also safely indulge in eating yogurt with live cultures, because it contains bacteria-derived lactase, which tends not to cause the usual symptoms of the condition.

Celiac Disease

Celiac disease is a malabsorptive disorder that affects people of all ages, genders and ethnicities. It can be present from birth or it can be triggered by surgery, a viral illness, pregnancy or emotional distress.

What Causes It? The exact cause of the disease is not well understood, but it is thought to be genetic in nature. Celiac disease results from the body thinking that gluten (a building block of grain products) is a harmful invader. The body then launches an immune response in an effort to destroy the gluten. This response ends up destroying the small intestine’s ability to adequately absorb nutrients. If the disease goes undetected and an individual continues to eat gluten-containing foods, the consequences can be disastrous. Iron-deficiency anemia, vitamin and mineral deficiencies and malabsorption are signs of the disease. Osteoporosis, hemorrhaging and intestinal cancer are possible end-stage consequences (See & Murray 2006).

What Are the Symptoms? People with celiac disease who consume gluten, the storage protein in wheat, barley or rye, may first start experiencing stomach cramps, which then often lead to a bout of foul-smelling diarrhea. Occasionally, the symptoms are more subtle and include weakness and fatigue, unexplained weight loss or even a weird, blistery, intensely itchy skin rash. Symptoms disappear and the small intestine heals completely if gluten is removed from the diet. But as soon as gluten is purposely or accidentally ingested, the inflammation immediately takes over and the disease symptoms return.

What’s the Best Diet Strategy? The treatment for celiac disease is quite simple: avoid gluten. But knowing what foods contain gluten is often an issue for clients with the disease. Because gluten is found in wheat, rye, barley and possibly oats, that means that bread, pasta, cookies and other grain products are off-limits unless they are labeled “gluten free.” That said, remind clients with the condition that meats, dairy products, vegetables, fruits and rice are naturally gluten-free and are thus safe dietary choices (See & Murray 2006).

Because food manufacturers have become more aware of celiac disease, more gluten-free products are now available on the market, especially in health food stores. But these foods are often triple the cost of their gluten-containing equivalents. Also, remind clients that gluten can be hidden in many products, such as frozen french fries, soy sauce, rice cereal, soup and hard candies, to name but a few.

Inflammatory Bowel Disease

Not to be confused with irritable bowel syndrome, inflammatory bowel disease (IBD) is actually two separate disorders: Crohn’s disease and ulcerative colitis. Unlike IBS, which is not life threatening, at its worst IBD can lead to severe disability and ultimately death.

Crohn’s Disease. Crohn’s disease can cause inflammation to any part of the GI tract, from the mouth to the anus, although damage is most often done to the ileum, the lower portion of the small intestine. Like many other GI disorders, Crohn’s disease is not well understood, though it is thought to be, at least in part, genetically inherited. As with celiac disease, some trigger causes the body’s immune system to attack the lining of the GI tract. The difference is that with Crohn’s disease, no one knows what the trigger is. Some speculate that perhaps a type of bacteria, food or protein causes the immune reaction. Regardless, the consequences of this inflammation can be severe, leading to malnutrition, intestinal blockage, and ulcers that tunnel through to other areas, such as the anus, bladder, vagina and skin. The ulcers can easily become badly infected. Other signs of Crohn’s disease include abdominal pain, bloody diarrhea, rectal bleeding, weight loss, fever and extraintestinal symptoms like mouth sores and eye inflammation (NIDDK 2006).

Ulcerative Colitis. Ulcerative colitis is also characterized by inflammation of the GI tract. However, unlike Crohn’s disease, ulcerative colitis is limited to the rectum and colon. Ulcers form in the areas where inflammation has killed the cells and then bleed, causing bloody, mucus-filled diarrhea. Anemia, fatigue, weight loss and decreased appetite are other symptoms of ulcerative colitis. Joint pain and skin lesions are sometimes experienced.

Ulcerative colitis is usually diagnosed in people aged 15–30 and less often in those aged 50–70, although the condition can begin at any age. Five percent of people with ulcerative colitis eventually develop colon cancer (NIDDK 2006).

What’s the Best Diet Strategy for IBD? Although nutrition is never the sole treatment for IBD, smart nutritional choices play an important role in the management of the two diseases. During an acute bout of IBD or in those who have more severe symptoms, aggressive nutritional therapy, such as tube or intravenous feeding, may be indicated.

During periods of remission from either Crohn’s disease or ulcerative colitis, nutritional management should focus on preventing severe nutritional deficiency, which can result from malabsorption, insufficient caloric intake, increased nutrient losses from the gut and drug-nutrient interactions.

People with IBD are encouraged to eat a nutrient- and calorie-dense diet with a particular emphasis on the following nutrients and their respective food sources (Goh & O’Morain 2003):

  • calcium (dairy products)
  • vitamin D (fortified dairy products)
  • folate (dark leafy greens, fortified grains, strawberries)
  • vitamin B12 (lean beef and other meat products)
  • zinc (seafood, spinach)

Dealing With GI Diseases for Life

Nutrition plays an important role in the disease process of many gastrointestinal ailments. While the culprit foods and their antidotes may be obvious for some diseases, in other cases it may take some investigative work to figure out which foods help and which hurt.

When symptoms act up, GI disease sufferers should seize the opportunity to better understand their illness (and maybe also to see their doctor regularly). Questions they can ask themselves include, “What exact symptoms do I have? When do the symptoms occur? What did I eat today? What foods always make me feel sick? What foods always make me feel better?” Keeping a food diary can help them identify the types of foods that tend to trigger symptoms of common gastrointestinal ailments.

This quick exercise may help uncover the individual nutrition choices that can alleviate many—though not all—of the most annoying gastrointestinal ailments.

The most prevalent GI disorder is irritable bowel syndrome (IBS), a poorly understood disorder of the large intestine that causes recurrent abdominal pain, bloating,
discomfort and changes in the frequency and consistency of bowel movements.

The Digestive Systemesophagusstomachlivergall bladderpancreassmall

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ddiseases/pubs/ibs_ez/; retrieved Nov. 13, 2006.
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Natalie Digate Muth, MD, MPH, RD

"Natalie Digate Muth, MD, MPH, RDN, FAAP, is a board-certified pediatrician and obesity medicine physician, registered dietitian and health coach. She practices general pediatrics with a focus on healthy family routines, nutrition, physical activity and behavior change in North County, San Diego. She also serves as the senior advisor for healthcare solutions at the American Council on Exercise. Natalie is the author of five books and is committed to helping every child and family thrive. She is a strong advocate for systems and communities that support prevention and wellness across the lifespan, beginning at 9 months of age."

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