Irritable bowel syndrome (IBS), is one of the most common functional gastrointestinal disorders (FGID) affecting 10-20% of the adult population worldwide, yet most challenging when it comes to treatment. The condition is most commonly found amongst Western populations, particularly affecting females and younger age groups.

Its symptoms are chronic, recurrent and heterogeneous, manifesting as lower abdominal pain or discomfort, excessive gas production/ borborygmi, abdominal bloating and distension, altered bowel motility (constipation and/or diarrhoea) and nausea. Some patients may also suffer extra-intestinal symptoms, such as urinary frequency, headache, dyspareunia, heartburn, back pain, sleep problems, fibromyalgia and chronic fatigue. In addition to physical symptoms, IBS sufferers are affected mentally, with mood swings, hopelessness, anxiety and depression being the most common emotional symptoms. IBS is not known to cause bowel cancer or excess mortality, however, it can seriously reduce quality of life, interfering with daily activities, social and occupational life, and often leads to excessive healthcare costs.

What causes your IBS?

The disorder is proposed to be due to a complex interaction between biological and psychosocial factors:

• acute gastroenteritis
• small intestine bacterial overgrowth (SIBO)
• increased visceral sensitivity (where nerves and muscles in the bowel are extra sensitive resulting in pain, discomfort and spasms)
• abnormal gut motor function
• disturbed gas metabolism
• altered gut permeability
• impaired viscerosomatic reflexes and abdominal-wall dystony
• food intolerances
• sex hormones and genetic predisposition

are all plausible mechanisms leading to altered gut flora and microscopic inflammation, which in turn may trigger IBS onset.

Additional factors that your doctor may underestimate:

• Emotional factors – feelings of anxiety, resentment and guilt, psychologically many patients are obsessive-compulsive personalities, trauma, divorce, accident, bereavement
• Prescription drugs, laxative abuse
• Smoking – nicotine affects motility of the colon
• Lack of dietary fibre
• Yeast overgrowth (candida)
• Caesarian pregnancy and lack of breastfeeding – as antecedents to imbalanced gut flora and hence IBS
• Spinal maladjustment (trapped spinal nerve)
• Insufficient chewing – amylase and lipase in saliva start breaking down carbohydrates and fats, hence less fermentation lower down in the digestive tract, and also send signal to the other parts of the digestive system to prepare for food digestion
• Chronic use of antibiotics, OCP, HRT and steroids, iron, anxiolytics – detrimental effect on gut flora

Food Intolerances and IBS

Food intolerances are among the most common IBS mediators :

1.  Lack of enzymes e.g. lactase enzyme to break down lactose from dairy into galactose and glucose. Lactose ferments in the gut causing gas, pain and bloating due to hydrogen production. There may also be lack of pancreatic digestive enzymes, insufficient hydrochloric acid from the stomach and/or insufficient bile to break down fats, all of which lead to insufficient nutrient absorption, creating a vicious cycle
2.  Reaction to chemicals, all of which can cause different IBS symptoms, depending on the individual, but mainly bloating, pain and diarrhoea: natural e.g. amines (citrus fruit, cheese, red wine, chocolate, coffee), or additives: MSG, sodium benzoate, nitrates, sulphites, sweeteners (aspartame, sorbitol) and colours (sunset yellow and tartrazine).
3.  Raised IgG antibodies – associated with inflammation, which damages the wall of the intestines and can cause leaky gut. Inflammation can also trigger IBS symptoms like pain and spasms associated with particular foods. Gluten intolerance: IBS-like symptoms, as well as fatigue, headaches and joint pains; gluten is a sticky protein that “glues” on the wall of the intestine impairing sufficient digestion and absorption of nutrients. Dairy intolerance – can be due to lactose, casein or whey, fat).

Other dietary factors that can trigger IBS

• Added and refined sugars – not only disturb the balance of the gut flora, but also decrease blood sugar levels. Stress hormones are produced in response, triggering IBS symptoms
• Resistant starch (e.g. amylose in legumes, potatoes, green bananas, rice) – It resists digestion and ferments in the large intestine causing IBS symptoms
• High saturated fat (dairy, meat) – can result in quicker or slower stomach emptying and muscle spasms. Fat malabsorption means Omega 3 is harder to absorb what can increase inflammation, aggravating pain and bloating

References 

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