What is Irritable Bowel Syndrome (IBS)?
IBS is a condition that produces symptoms similar to those of inflammatory bowel disease (IBD), but they aren’t the same and involve very different treatments.
Symptoms can vary widely among individuals, but most IBS sufferers experience some degree of chronic and persistent abdominal pain or discomfort, gassiness, abdominal bloating and distention, constipation, diarrhea, or constipation alternating with diarrhea.
People with IBS are also more likely to have a disorder such as chronic fatigue syndrome, fibromyalgia, chronic pelvis pain, and temporomandibular joint (TMJ) disorder.
Finding the Right Diet for IBS
Researchers have determined by avoiding foods that include fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, IBS symptoms are significantly reduced. This diet is known as the low-FODMAP diet.
All foods to avoid on the FODMAP list are osmotic (they pull water into the intestinal tract). They may not be digested or absorbed well and could be fermented upon by bacteria in the intestinal tract when eaten in excess.
In one study with IBS subjects, symptoms were reduced by more than half when they followed the FODMAP diet, and all the symptoms assessed were reduced to a level considered good symptom control. According to the research results, a difference in symptoms may be seen immediately, and the greatest symptom control may happen after 7 days of achieving and maintaining the low-FODMAP diet.
If FODMAP carbs are causing the symptoms, relief can occur in just a few days.
Foods to Limit on the FODMAP Diet
Oligosaccharides include fructans and galactans.
- Fructans: wheat, rye, onion, garlic, Jerusalem and globe artichoke, asparagus, beetroot, chicory, dandelion leaves, leek, radicchio, the white part of spring onion, broccoli, Brussels sprouts, cabbage, fennel, chocolate, and prebiotics such as fructooligosaccharides, oligofructose, and inulin.
- Inulin can cause overgrowth of intestinal methane-producing bacteria. This can lead to gas and bloating.
- Galactans: dry beans (pinto beans, kidney beans, lima bean, etc.), dry peas, garbanzo beans, black-eyed pea, lentils, soy
Disaccharides include lactose containing foods such as milk, butter, yogurt, frozen yogurt, kefir, cheese, and some sour cream.
Monosaccharides include fructose. Some foods with high ratios of fructose include fruit juice (ie: apple and pear), honey, high fructose corn syrup, agave nectar, and dried fruit.
Polyols are found naturally in some fruit and vegetables, especially plums, cherries, peaches, apricots, nectarines, apples, avocados, blackberries, lychees, pears, watermelon, cauliflower and mushrooms.
Polyols are also used as artificial sweeteners. Avoid sugar alcohols such as sorbitol, mannitol, xylitol, and maltitol.
Foods to Eat on the FODMAP Diet
Dairy: lactose-free or reduced-lactose dairy products, almond milk, rice milk, small amounts of hard cheese (cheddar, colby, parmesan, swiss), mozzarella, sherbet
Fruits: small servings of berries and citrus fruits, grapes, pineapple, honeydew, cantaloupe, kiwi, rhubarb
Vegetables: bell peppers, bok choy, cucumbers, carrots, celery, eggplant, lettuce, leafy greens, pumpkin, potatoes, squash, yams, tomatoes, zucchini, corn
Grains: rice, oats, cornmeal, polenta, gluten-free grains, gluten-free flour, quinoa
Protein: lean meats, fish, shellfish, and poultry
Sweeteners: small servings of granulated sugar and maple syrup are usually well-tolerated.
Bottom Line: Following the FODMAP diet is shown to improve many undesirable IBS symptoms. The goal of the diet is to find the most liberal and varied diet possible while still keeping symptoms under control. For more information, go here.
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods