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Most people have suffered an occasional bout of bloating, gas, constipation, even diarrhea. But for people with irritable bowel syndrome, these uncomfortable, often painful symptoms persist, frequently interfering with daily life. While foods don't cause the syndrome, altering your diet can help control and treat symptoms. Skipping meals, eating too much fat and too little fibre, and drinking too much coffee can trigger and aggravate difficulties.

As many as 20 per cent of Canadians have irritable bowel, a disorder that affects significantly more women than men. Doctors refer to it as a functional disorder, since there's no sign of abnormality when the large bowel, or colon, is examined, but it doesn't work as it should. It's thought symptoms result from overly reactive and/or extra sensitive nerves that control muscles in the bowel.

The syndrome's main symptoms are abdominal pain or discomfort and altered bowel habits. Most people experience either diarrhea or constipation, some have both and alternate between them. Other symptoms include mucus in the stool, abdominal bloating and a feeling of incomplete emptying after a bowel movement.

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It's not known what causes the condition to develop in the first place, but hormones, stress, bacterial infection, antibiotic use, food sensitivities and disorders that affect intestinal muscle contractions are among the suspects. It is known, however, that certain foods can stimulate reactions in the gut. If you have the condition, eating too much of these foods might bring on or worsen your symptoms.

To get relief, the best place to start is your diet. Before making changes -- especially unnecessary ones -- keep a daily food and symptom journal for two weeks to identify what foods, or patterns of eating, set off symptoms. Keep track of meal and snack times, types of foods eaten and portion sizes. Note symptoms, as well as what time they start and end. Keep in mind that factors such as stress, certain medications (e.g. magnesium-containing antacids), the menstrual cycle, and a lack of physical activity may also aggravate symptoms.

The influence of diet on irritable bowel is unique to each person. No single piece of dietary advice will work for everyone. Many, or only a few, of the following strategies may help ease symptoms.

Identify food triggers

Fatty foods (fatty meats, fried foods, cream sauces), caffeine, chocolate, alcoholic beverages, carbonated beverages, sorbitol (an artificial sweetener used in sugar-free gum and candy) and fructose (the simple sugar found in honey and many fruits) can worsen cramping and diarrhea in many people with the syndrome. Limit gas-producing foods

Foods that contain poorly digested carbohydrates can cause intestinal gas and may contribute to bloating. Foods that produce gas include beans, lentils, nuts, broccoli, brussel sprouts, cabbage, cauliflower, turnip, onions, garlic and large portions of refined (white) starchy foods. If beans bother you, trying using Beano, a commercial enzyme sold in pharmacies that helps break down the gas-producing starches in beans. Gassy vegetables are usually better tolerated cooked, rather than raw, and if eaten in small portions.

Other foods that contribute to excess gas include chewing gum, carbonated beverages, and sipping on hot beverages.

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Take care with lactose

Milk products can worsen symptoms if you are lactose intolerant. In lactose intolerance, your body lacks lactase, the enzyme needed to break down and absorb the milk sugar, lactose. Undigested lactose remains in the gut causing excess gas, bloating, cramps and sometimes diarrhea.

Most people with mild or moderate lactose intolerance can drink milk in small quantities and tolerate yogurt (yogurt has less lactose than milk and is emptied from the stomach more slowly). Eating solid food with dairy foods will also improve lactose digestion because it slows the rate at which food enters the small intestine.

Lactose-reduced dairy products that have been pretreated with lactase are available in supermarkets. You can also use commercial lactase-enzyme drops or capsules, such as Lactaid. If reducing lactose improves your symptoms, increase your intake of non-dairy calcium foods (e.g. enriched soy or rice beverages, firm tofu, leafy green vegetables) or take a calcium supplement.

Gradually increase fibre

For many people with IBS, increasing fibre helps control symptoms. Fibre reduces constipation by softening the stool, making it easier to pass. People whose symptoms include constipation should include sources of insoluble fibre such as wheat bran, whole grain cereals, fruits and vegetables. Too much wheat bran, however, can worsen diarrhea. If you have that problem , it's best to consume more soluble fibre, which takes longer to leave the digestive tract. Sources of soluble fibre include oat bran, barley, psyllium husks, citrus fruit and legumes.

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Regardless of the type of fibre you experiment with, increase your intake gradually over a period of weeks. Drink at least nine cups (2.2 litres) of water each day, preferably one hour before or one hour after meals. Drinking water with meals may make food move through the gut faster.

Add a probiotic

Foods and supplements that contain lactic acid bacteria are called probiotics, the opposite of antibiotics. These so-called "friendly" bacteria normally reside in the intestinal tract, where they help to maintain healthy gut function. It's been suggested that people with irritable bowel don't have enough friendly bacteria, and adding probiotics may reduce symptoms. A few studies, but not all, suggest that consuming foods that contain Bifidobacteria reduce abdominal pain and bloating in people with the syndrome.

Lactic-acid bacteria are found in yogurt, kefir (a yogurt-like drink) and supplements. Research suggests that a daily dose of one billion live Bifidobacteria cells may reduce symptoms. All yogurts are made with two lactic-acid bacteria ( Lactobacillus bulgaricus and Streptococcus thermophilus), but only a few brands, such as Activia (Danone) and Astro Biobest, have added Bifidobacteria to their products. Eat at regular times

To help regulate bowel function, don't skip meals. Eat well balanced, low-fat meals at the same time each day.

People with diarrhea as part of the syndrome may find eating smaller meals more frequently reduces symptoms.

Be active

Regular physical activity reduces stress and helps stimulate regular bowel contractions. Aim for 30 minutes of moderate physical activity each day.

If you have a persistent change in bowel habits, or any symptoms of irritable bowel syndrome, consult your doctor, who can help find ways to manage symptoms and rule out other more serious bowel conditions.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic,

is on CTV's Canada AM every Wednesday. Visit her website at

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