Knowing how to manage irritable bowel syndrome can be frustrating. There’s no one-size-fits-all treatment since its symptoms and triggers can vary greatly from person to person.
According to new research, a good starting point is addressing your diet. Doing so, the findings suggest, is more effective at relieving IBS symptoms than medication.
Here’s an IBS primer, plus evidence-based diet strategies that can offer relief.
What is IBS?
IBS is a chronic, often debilitating gastrointestinal disorder that affects nearly one in five Canadians, women more often than men.
Hallmark symptoms are abdominal pain and altered bowel habits – constipation, diarrhea or a combination of the two. Other symptoms may include bloating, visible abdominal distention, flatulence and urgency to have a bowel movement.
Certain foods, medications, emotional stress and hormone fluctuations can trigger or worsen IBS symptoms.
If you think you might have IBS, consult your doctor for proper diagnosis.
What causes IBS?
The exact cause of IBS is unknown but several factors are thought to play a role.
A highly sensitive gut wall may be to blame. Normal changes in gut activity can cause nerves in the gut to send messages to the brain causing enhanced pain perception.
IBS may also be caused by altered gut motility. Intestinal muscles may move digested food through the intestines too quickly or too slowly.
An imbalance of gut microbes, inflammation in the gut and a prior gastrointestinal infection are other possible causes.
Managing IBS
Diet and lifestyle modifications are typically recommended to keep IBS at bay. Increasing physical activity and getting proper sleep, for example, can help ease symptoms by reducing stress.
Cognitive behavioural therapy, which targets the brain-gut connection, has also been shown to help manage IBS.
If symptoms are severe, medication targeted at the dominant ones may be recommended.
There is evidence, though, that dietary changes ought to be considered as an initial treatment for IBS.
A recent randomized controlled trial, conducted in 300 adults with moderate to severe IBS, compared the effectiveness of three treatments:
1) a low FODMAP diet paired with standard IBS diet advice;
2) a low-carbohydrate diet;
3) medication that targeted symptoms.
After four weeks, all three treatment options showed significant and meaningful improvement in symptom severity. The two dietary interventions, however, outperformed medication treatment.
During a six-month follow-up period, FODMAP reintroduction was successfully completed and both diet groups experienced sustained improvements in IBS symptoms and quality of life.
The findings were published April 18 in the journal Lancet Gastroenterology and Hepatology.
Dietary approaches to ease IBS symptoms
Before making unnecessary or restrictive diet changes, keep a food and symptom journal for two to three weeks to identify foods that may be setting off your symptoms.
I strongly recommend working with a dietitian to determine the right approach for you and to guide you through the process.
Low FODMAP diet
FODMAP is an acronym for “fermentable oligosaccharides, disaccharides, monosaccharides and polyols.” These short-chain carbohydrates, found in a wide range of foods including milk, yogurt, many fruits and vegetables, garlic, beans and lentils and wheat-based products, are poorly absorbed in the small intestine.
As they move through the small intestine, they pull in water. In the large intestine, they’re fermented by gut bacteria causing gas. This water and gas stretches the intestinal wall, causing abdominal pain.
The diet involves three phases:
1) eliminating high FODMAP foods for two to six weeks;
2) reintroducing FODMAPs, one at a time, to determine which ones trigger symptoms and which ones don’t;
3) increasing variety in the diet by adding back tolerated high FODMAP foods.
Clinical trials show that 75 per cent of people with IBS can reduce their symptoms by following a low FODMAP diet. It’s recommended as the first dietary treatment of choice for IBS.
For people who don’t respond to a low FODMAP diet, simpler dietary adjustments can help.
Avoid potential triggers
Fatty foods (for example, deep-fried foods, pizza, creamy pastas and ice cream) can cause abdominal pain and bloating and worsen diarrhea.
Caffeine is a commonly reported trigger for diarrhea among people with IBS. The stimulant is thought to speed up the movement of intestinal contents.
Eating spicy foods has also been associated with IBS-related abdominal pain.
Alcohol is a direct irritant to the gastrointestinal tract and, for some people, may contribute to IBS symptoms by causing gut inflammation or altering intestinal motility.
Consider fibre
If diarrhea is your main IBS symptom, soluble fibre may help. This fibre absorbs water in the digestive tract, making stools firmer and slower to pass.
Good sources include psyllium husk supplements, oats, oat bran, barley, oranges, peas and beans and lentils.
If it’s constipation that bothers you most, try adding sources of insoluble fibre, which increase stool bulk and the speed at which stool moves through the colon. These include wheat bran, bran cereals, whole wheat pasta and whole rye bread.
Psyllium fibre supplements are also effective.
Increase your intake of fibre gradually and be sure to increase your water intake as well.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD
Leslie Beck