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IBS: Every step of the way

Worried that you may have irritable bowel syndrome (IBS)? Dietitian and digestive health expert Dr Sue Shepherd cuts through the confusion and explains the steps you need to take to address your symptoms.

Irritable bowel syndrome (IBS) is the most common gastro-intestinal disorder, thought to affect around 15 per cent of the population worldwide. But the type, number and severity of symptoms and triggers of IBS can vary greatly between individuals — making it difficult to diagnose and, therefore, to treat.

If you’re concerned you may have IBS, or if you are confused about how to manage it if you have already been diagnosed, read on for our comprehensive step-by-step guide to the action you need to take: from getting diagnosed, to altering your diet and addressing any problems.

There is an official diagnostic criteria used to diagnose IBS, called the Rome III criteria. The Rome III criteria defines IBS as a condition where there is abdominal pain and altered bowel habits (either constipation or diarrhoea or a combination of both), in the absence of any other identifiable disease that may be causing those symptoms.

Outside the research laboratory, however, the symptoms of IBS expand more widely beyond abdominal pain and altered bowel habits. Other common symptoms include bloating, excess wind and abdominal distension.

Your doctor may not mention the Rome III criteria as it is usually used to ensure research studies are ‘comparing apples with apples’.

Sufferers can experience a broad range of symptoms, including:

  • Abdominal pain and discomfort
  • Bloating
  • Changes in bowel habits (ie. constipation and/or diarrhoea)
  • Heartburn
  • Nausea
  • Distension
  • Excessive wind
  • A noisy abdomen
  • Pain in the rectum

If you suspect you have IBS, it is worth investigating. IBS accounts for around five per cent or more of GP visits globally, and for 20-50 per cent of referrals to gut specialists (gastroenterologists).

It is estimated that more women than men are affected in a 2:1 ratio, and about half of those with IBS are under 35 years old.

It has also been estimated that about 30 per cent of IBS sufferers take sick leave, with 50 per cent of these absent from work for more than two weeks in a year. In a nutshell, this common disorder is a substantial source of ill-health in the community.

1.  See your doctor

If you have any of the common IBS symptoms (see above) on a regular basis, you need to discuss them with your GP — don’t ignore them. Also, don’t self-diagnose and assume you have IBS as it could be something more serious.

Your GP will ask about ‘red flags’ (ie. concerning symptoms) including blood in the stools, unexplained weight-loss of 5kg or more, symptoms that wake you up in the night, family history of bowel cancer, and if you were over the age of 50 when symptoms began.

Based on your symptoms, your GP may rule out conditions such as bowel cancer, coeliac disease, Crohn’s disease, ulcerative colitis and gynaecological issues (including endometriosis and ovarian cancer). Your GP may also refer you on to a gastroenterologist for further investigation. If there is no other cause identified for your symptoms, it is then likely you have IBS.

2.  See a dietitian

Many people who suspect they have IBS will start to change their diet in an effort to control their symptoms. If you suspect food is a culprit, however, we recommend that you consult with a dietitian first, as you may end up cutting out more than you need to, which could lead to you missing out on vital nutrients in your diet. A dietitian can help you replace foods you need to limit with other nutritious foods, to ensure your diet is balanced and nutritionally adequate.

Cutting out foods without consulting a professional can also complicate a diagnosis. For example, many people suspect wheat causes their symptoms so they cut it out. However, as most people with symptoms of IBS need to be investigated for coeliac disease, it’s important you are still eating gluten (found in wheat, rye, barley, oats and foods made from these) when you are being tested, otherwise the results will be inaccurate.

If you have already removed gluten from your diet then you need to tell your doctor, who will recommend you eat foods containing gluten again before you are tested for coeliac disease.

3.  Consider having hydrogen/methane breath tests done

Breath tests to identify sugar malabsorption (eg. lactose, fructose, sorbitol) can be very useful to help indicate dietary triggers for your IBS. Breath tests are not essential but can be very useful to assist in refining the dietary advice your dietitian recommends.

How and why people get IBS is unknown. What is known, however, is that it is a chronic disorder and symptoms can vary in frequency and severity.

There are many potential triggers for IBS. These include diet, anxiety or stress, the efficiency of your gut and some medications and herbal supplements. Your GP or dietitian can help you to figure out what your triggers are and to come up with ways of managing them. This is another reason it is so important to consult a professional rather than trying to diagnose yourself.

One feature of IBS is something called ‘visceral hypersensitivity’. This means the nerve endings that surround the large bowel are very sensitive to things like gas production. Normally, our nerve endings aren’t so fussed about some gas production. However, in people with IBS, who can have more gas production than in people without IBS (eg. via fermentation of FODMAPs — see page 38), the nerve endings have a lower threshold of what they will tolerate before they are aggravated. These very sensitive nerve endings then tell the brain that they are not happy and the brain can respond by further increasing symptoms. The communication between the brain and the bowels is called the gut-brain axis, and the chatter that goes on between the gut and the brain is altered and exaggerated in people with IBS.

Trigger: Stress and anxiety

If anxiety and stress are major triggers for your IBS, you could talk to your healthcare professional about stress management techniques. Some research has found hypnotherapy can be useful as it targets improving the subconscious gut-brain axis chatter that is impaired in people with IBS.

And try to minimise your stress — it is something that can make IBS symptoms worse! Include relaxing activities such as meditating, reading, exercise or listening to music in your daily routine and ensure you get enough sleep (about seven to nine hours each night for adults).

Trigger: Food and drink

It makes sense to have a look at what and how you are eating. Do you eat hurried, stress-filled meals where you only have three minutes for lunch before you have to attend to your next task? Do you skip meals? Then try to establish a regular eating pattern. If you are consuming too many cups of coffee, too many rich greasy meals and too much alcohol, it is wise to cut back. Moderation is key.

The same goes with fibre — enough is important but too much can also cause you grief. The recommended fibre intake for men is 30-38g per day, and 25-28g per day for women. Choose foods that contain both soluble fibre (eg. fruits, vegetables, oat bran, linseed/flaxseed, psyllium) and insoluble fibre (eg. nuts, seeds, wholegrain foods and popcorn). Also, drink plenty of fluid — preferably water — and limit fruit juice or carbonated drinks.

If you follow a fairly healthy eating plan, it is still likely your diet plays a role in your IBS. Dietary triggers are usually the most common for IBS and include:

  • FODMAPs (Fermentable oligosaccharides, disaccharides, monosaccharides and polyols) — the most common dietary trigger. FODMAPs are sugars found in foods that provide ‘fast food’ for bacteria. They cause the bowel to distend by drawing in more fluid and rapidly generating gas when they are fermented by bacteria in the bowel. Breath tests may assist to see if they are a problem for you.
  • Food chemicals (eg. salicylates, amines, glutamates) found in many commonly eaten foods).
  • Fat in excess (more than 30 per cent of your total daily energy intake).
  • Alcohol in excess (more than two standard drinks a day for most people).
  • Caffeine in excess (in caffeine-sensitive people).
  • Fibre — too much or too little.

If you know that the foods you eat contribute to your symptoms, you are not alone. Seventy per cent of patients in a Scandinavian study reported they had IBS symptoms related to food. This is why you should consult with a dietitian for advice about which foods to limit and which foods to use as alternatives to assist in minimising your symptoms.

In a study performed in Melbourne, 72 per cent of patients with IBS who were taught about a low-FODMAP diet significantly improved their symptoms. A low-FODMAP diet is now recognised internationally as the first line of dietary therapy for IBS. If you notice wheat makes you feel bloated but you don’t have coeliac disease, then perhaps a low-FODMAP diet will help. A low-FODMAP diet isn’t just for wheat intolerance, though. Foods such as apples, pears, onions and stone fruits can be triggers, too. A dietitian who specialises in gastrointestinal nutrition will be able to discuss with you whether a low-FODMAP diet is appropriate for you.

Trigger: Medications and supplements

Some medications may cause gastrointestinal symptoms. For example, many cough syrups contain sorbitol — a type of FODMAP. If your medications cause you gut symptoms, speak to your doctor and request an alternative drug with a similar function that is unlikely to cause symptoms. Many herbal supplements and naturopathic tonics contain components of unusual origin and details of these are often not provided when they are prescribed. If you suspect any that you are taking may cause gastrointestinal symptoms, speak to your doctor to request an alternative.

FODMAPs are sugars that occur naturally in foods and can cause symptoms of IBS in many people. The most common FODMAP culprits are listed below, with the type of FODMAP listed in brackets next to it.

  • Apples (excess fructose and polyols)
  • Artificial sweeteners (polyols including sorbitol, mannitol, xylitol, maltitol)
  • Wheat (fructans) — but don’t exclude it until coeliac disease has been investigated
  • Milk (lactose)
  • Legumes, lentils, chickpeas (fructans and GOS — galacto-oligosaccharides)
  • Stone fruit (polyols)
  • Leeks (fructans)
  • High fructose corn syrup (excess fructose)
  • Garlic — in large amounts (fructans)
  • Onions (fructans)
  1. Don’t self-diagnose – it could be something else. Also, don’t ignore your symptoms and hope they will go away. Go to your GP and explain your symptoms.
  2. Don’t go on a gluten-free diet to relieve your symptoms until you have been investigated for coeliac disease.
  3. Consider having hydrogen/methane breath tests for fructose, lactose and sorbitol malabsorption to assist in identifying if FODMAPs are an issue for you.
  4. See a specialist dietitian for expert advice on what foods to limit and what to replace them with.
  5. Take part in stress-reducing activities (eg. meditating, reading, exercise, listening to music), and make sure to get enough sleep (about seven to nine hours each night for adults).
  6. Ensure adequate fibre intake (25g/day for women and 30g/day for men), made up of both soluble and insoluble sources.
  7. Drink plenty of water – aim for six to eight glasses each day.
  8. Establish a regular eating pattern – don’t skip meals and limit fat, alcohol and caffeine-rich foods and beverages.
  9. Pass wind! Holding it in can make symptoms worse.
  10. Read what the experts say – the book Food Intolerance Management Plan by Dr Sue Shepherd (dietitian) and Dr Peter Gibson (gastro-enterologist) is available in bookstores and from: www.shepherdworks.com.au.

More information from the HFG archives

Date modified: 18 February 2019
First published: Jun 2012


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