Individuals affected by irritable bowel syndrome (IBS) experience a change to their normal bowel movements, digestive pain and discomfort. IBS can be highly inconvenient and embarrassing, causing people to adjust their daily routines in order to control erratic bowel movements. At its worst, IBS is debilitating, with sufferers fearing to leave the house or eat away from home. IBS sufferers often identify suspect food or food groups, as a cause of their symptoms, however this can sometimes be due to coincidence and lead them to unnecessarily exclude multiple food groups. If IBS remains unresolved, seeking expert dietary and lifestyle advice may help sufferers identify their underlying problems and food triggers.
How common is IBS?
IBS is a very common condition estimated to affect around 10% of the population in the UK.
What are the symptoms of IBS?
IBS symptoms include abdominal pain and discomfort in combination with some of the following changes to regular bowel habits:
- Consistency of stool (for example diarrhoea, constipation or alternating patterns of diarrhoea and constipation).
- Regularity of bowel movements.
- Improvement in pain and discomfort following a bowel movement.
Other commonly reported symptoms of IBS include:
- Bloating
- Flatulence (wind)
- Belching
- Urgency of defecation
- Difficulty or straining to pass stool
- Feeling that bowel movement is incomplete
- Steathorhea (fat malabsorption)
- Tiredness and fatigue
- Food sensitivities
- Headaches and migraine
- Low mood
- Depression
- Disturbed sleep
- Back pain
- Menstrual cramps
- Nausea
- Bladder problems
What are the causes of IBS?
IBS is diagnosed following the exclusion of any other medical condition that can cause similar symptoms, for example parasitic infection, gut transit problems, coeliac disease, small intestinal bacterial overgrowth or certain cancers. IBS is associated with an apparently physically normal digestive system displaying no signs of disease to explain the abnormalities to normal function. What triggers the initial onset of IBS is still not entirely understood. It seems likely that individuals have different triggers that set off their IBS, which may account for the varying factors that can aggravate IBS. Factors suspected of triggering, and/or aggravating IBS symptoms include:
Altered gut motility: gut motility describes the the rhythmic contractions of the digestive system controlled by nerves, hormones and muscles that move food along in the digestive tract. Gut motility may become dysfunctional, becoming either too strong or too weak in IBS suffers. This results in the transit of food being too fast or too slow. Psychological and physical factors such as stress, emotions, sedentary behaviour, exercising excessively and eating too quickly or on the go, may affect the gut’s normal function.
Gut-brain link: the abdominal pain characteristic of IBS has been attributed to an increased sensitivity to pain in the gut. Normal digestive function, such as the contractions of gut walls, is consequently interpreted incorrectly as pain by the nervous system. Another gut-brain link concerns the great number of hormone-producing cells in the gut, which enable communications between the gut and the brain concerning digestive function. It is proposed that with IBS, these hormone cells may be defective, resulting in compromised communication and consequent disruptions to digestive function.
Infection: IBS is known to sometimes follow a bout of gastroenteritis (an infection in the gut), which can be caused by disease-causing bacteria, viruses or parasites. There are also parasitic organisms that an individual can contract that although not universally agreed upon as ‘disease-causing’, may be responsible for triggering symptoms of disordered digestion in sensitive individuals.
Psychological and stress: many IBS sufferers report an exacerbation of symptoms in stressful and emotional situations. Stress has been shown to have a more pronounced affect on gut motility in people with IBS than people without.
Hormonal imbalance: IBS affects twice as many women as men, which is why it is thought that hormone imbalances may play some role in triggering the condition.
Inflammation: low levels of inflammation may be present in the gut walls of people with IBS. This may be caused by a mild immune reaction to food, gut bacteria or toxins.
Gut bacteria: the bacteria that reside on the wall of the gut (known as the microbiota) are important for normal gut function, including digestion of food and immune tolerance. Differences have been found between the gut bacteria of people with IBS and those without the condition, which may account for altered gut function in some people with IBS.
What is the treatment for IBS?
Management of IBS can include:
- Dietary advice.
- Physical activity.
- Prescriptive and non-prescriptive drug treatment for management of symptoms.
- Psychological intervention.
What can you do to support IBS?
It is advisable to consult a fully qualified practitioner on which approach might work best for you, particularly before considering excluding certain food groups. Without appropriate advice, diets may be adopted that are nutritionally inadequate and foods may be unnecessarily excluded without a clear rationale or a plan to trial their re-introduction to the diet. With IBS there does not appear to be a ‘one size fits all’ solution: what is right for one person may be unhelpful for another, depending on what factors are underlying and triggering their IBS. Nutritional therapy approaches to support IBS may include the following strategies:
- Low FODMAPs protocol
- Modification of specific nutrients, e.g. dietary fats, sugars, fibre.
- Lactose free diet
- Elimination diet to identify food triggers
- Gluten free diet
- Specific carbohydrate diet
- Anti-inflammatory diets
- Probiotic bacteria or yeast and/or pre-biotic supplements and food sources
Some general diet and lifestyle strategies that may support IBS include:
Reduce or eliminate sugar and refined or processed food: sugar may encourage overgrowth or imbalance of gut bacteria and poor gut motility. Refined and processed foods do not contain adequate fibre and nutrients to support gut health.
Exercise regularly: regular exercise can support good gut motility and may help to lower stress levels and increase positive emotions.
Counselling and cognitive behaviour therapy: may help individuals with IBS if their symptoms are worse during stressful times, or if their symptoms are adding to distress, or if they also suffer from depression and anxiety.
Limit or avoid alcohol: alcohol is a gut irritant, which could trigger IBS symptoms.
Limit or avoid caffeine in food and drinks: caffeine is a stimulant and can increase gut motility.
Avoid foods high in capsaicin (found in spicy chilli peppers and sweet peppers) if sensitive to these foods: this can irritate the gut in sensitive individuals, which could trigger gut pain, diarrhoea and indigestion.
Rest and digest at mealtimes: eating on the go and not chewing food thoroughly can give your digestive system a hard time. Always sit down to eat and take time to appreciate the sight, smell and taste of your meal to get your body into digestive mode.
Drink plenty of fluids: adequate hydration is important to replace water lost from the body daily through normal functions such as digestion and sweating (loose watery stools can increase water loss) and to support stool form.
Try to follow a good sleep routine: poor sleep may make IBS symptoms worse. A relaxing evening routine avoiding stimulating activities (such as watching television and using electronic devices), can help the body get into rest mode and encourage a good night’s sleep and lower stress levels.
Relaxation: if you find it hard to relax, practicing relaxation exercises may help to reduce stress, which can exacerbate IBS symptoms.