Irritable bowel syndrome (IBS)
Irritable bowel syndrome is a disorder of bowel function, rather than an anatomic abnormality. It affects 1 in 10 Americans, and about 1 in 6 women. About 900,000 people in the Chicago area have irritable bowel syndrome. IBS does not cause damage to organs or decrease life expectancy. However, it can decrease quality of life, decrease day to day function, cause stress, and raise concern about other gastrointestinal diseases.
IBS is often diagnosed in people below age 35. Those with a close relative are at higher risk. Some people develop IBS symptoms that last for a prolonged period after a gastrointestinal infection.
Symptoms of irritable bowel syndrome
IBS is associated with abdominal discomfort and change in bowel habits – constipation or diarrhea. It can be called mixed type, IBS-D (diarrhea-predominant), or IBS-C (constipation-predominant). Other symptoms may include bloating, muscle pain, fatigue, or urinary symptoms.
Diagnosis of irritable bowel syndrome
A physician can assist with diagnosis, and with ensuring that other diseases have been ruled out. The ROME III criteria are standard for IBS diagnosis. The ROME III criteria for IBS require recurrent abdominal pain or discomfort at least 3 days per month in last 3 months associated with two or more:
- Improvement after bowel movement
- Onset with change in bowel frequency
- Onset with change in stool appearance
It is important to rule out anatomic or structural problems, cancer, microscopic colitis, inflammatory bowel disease, and celiac disease if symptoms are suggestive. Bacterial overgrowth may also cause IBS-like symptoms. Extensive testing should be avoided unless concerning features are present.
Treatment of irritable bowel syndrome
It is important to treat symptoms in order to restore quality of life and daily function. The primary means include changes in diet and lifestyle, as well as stress reduction.
Diet for treatment of irritable bowel syndrome:
- Limit any foods that cause symptoms, and gas-producing foods: beans, cabbage, onions, broccoli, ‘cruciferous’ vegetables
- Avoid carbonated drinks, which introduce air into your intestine
- Avoid ‘sugar alcohols’, which are low-calorie sweeteners (other than isomalt, end in –ol: sorbitol, xylitol, mannitol, erythritol)
- Avoid gum, which can include sugar alcohols and cause air swallowing
- Try eliminating dairy
- Avoid chewing and eating quickly
- Avoid sudden increases in fiber intake – add fiber gradually
FODMAPs and the low-FODMAP diet
FODMAP stands for Fermentable, Oligosaccharides, Disaccharides, Monosaccharides, Polyols. Foods high in FODMAPs (see the table below) can make symptoms worse, primarily in people who have diarrhea-predominant symptoms.
| High FODMAP | Low FODMAP | |
|---|---|---|
| Breads | Barley, rye, wheat pasta, cous cous, granola, semolina | Oats, quinoa, gluten-free pasta, rice, popcorn, pretzels, tortilla chips |
| Fruits | Apples, apricots, raisins, prunes, blackberries, pear, mango, oranges, watermelon, nectarines, peaches, plums | Bananas, oranges, lemons, kiwi, raspberries, strawberries, honeydew melons, grapes |
| Vegetables | Garlic, onions, beans (soy, lima, kidney), cauliflower, Savoy,cabbage, mushrooms, sweet corn, peas, asparagus, artichokes, leek bulb, beetroot, celery | Alfalfa, cucumber, carrot, green and red peppers, potato, squash, broccoli, lettuce, tomato, bean sprouts, green beans, bok choy, eggplant, chives, fresh herbs, turnips, zucchini |
| Dairy | Milk, yogurt, soft cheese, cream cheese, ricotta cheese, ice,cream, custard | Cheddar, cottage cheese, mozzarella, Parmesan, Swiss cheese |
| Meat and substitutes | Sausages, chorizo | Beef, pork, chicken, fish, tofu, tempeh |
| Nuts and seeds | Cashew, pistachio | Peanuts, almonds (if less than 15), pecans, chestnuts, pumpkin seeds, walnuts |
| Sweeteners | High fructose corn syrup, isomalt, maltitol, mannitol, sorbitol, xylitol, honey | Sugar, Stevia, Splenda, Nutrasweet |
| Drinks | Coconut water, apple juice, soda (with high-fructose corn,syrup) | Black coffee, orange juice, beer (up to one), wine (up to one glass) |
Medications for IBS
Medications can be useful for treatment of irritable bowel if the above methods are ineffective. These include a number of over-the-counter and prescription medications to control symptoms. If these fail, the FDA has approved medicines such as Amitiza (lubiprostone) or Linzess (linaclotide) for IBS-C (constipation-predominant), or Xifaxan (rifaximin) or Viberzi (eluxadoline) for IBS-D (diarrhea-predominant). Some patients find that probiotics help their symptoms.
