The diet that could banish bloating for good
Sufferers of irritable bowel syndrome ( IBs) endure a series of embarrassing gut symptoms including diarrhoea, constipation, bloating, pain in the rectum, needing to pass stools urgently and painful stomach cramps. They may also suffer loud gurgly noises and excessive wind.
‘Patients will send me pictures of their bloated tummies at the end of the day — I think they worry that doctors don’t take them seriously,’ says gastroenterologist Dr Ana Wilson. ‘ A lot of them worry about what is going on and fear it’s something serious such as cancer.’ But it is not a straightforward diagnosis. ‘IBs is a number of illnesses with no specific cause and no single effective treatment,’ explains Alison reid, chief executive of the IBs Network charity.
‘ We know that some people develop symptoms after food poisoning (about 10 per cent), or a course of powerful antibiotics, or as a symptom of post-traumatic stress.’
It’s important to see your GP so that tests can rule out more serious conditions.
These include blood tests for anaemia, white cell counts and C-reactive protein (a marker for infection or inflammation).
Other tests include an antibody test for coeliac disease, faecal calproctectin (for inflammatory bowel disease) and faecal occult blood (for bowel cancer).
If these are negative, then it’s likely the cause is IBs — but there are other conditions.
Gastroenterologist Professor Julian Walters estimates that up to a third of people (at least one million) told they have IBs with diarrhoea as the main symptom actually have a condition called bile acid diarrhoea. ‘It can cause up to ten watery stools a day, flatulence, urgency and painful abdominal cramps,’ he says.
It’s caused when bile acids produced by the liver are not processed properly, so excess bile passes into the colon, stimulating salts and water secretion, and leading to watery diarrhoea.
There is a test for it — the seHCAT test — where the retention and loss of bile acids is measured over seven days.
A patient swallows a capsule containing bile acid and a tiny amount of radioactive tracer. This allows scans taken a week apart to show how the body is processing the bile acid.
THecondition can be treated with medication such as 9 colestyramine, colestipol and colesvelam. ‘But too many people are just told that they have IBs and are not offered a test’, says Professor Walters. He suggests asking for a test if you have persistent, frequent watery diarrhoea.
IBs-type symptoms can also be caused by small intestinal bacterial overgrowth (sIBO, see cover) and microscopic colitis, a type of severe watery diarrhoea. the latter is caused by changes in inflammatory cells in the colon visible only under a microscope: these reduce the amount of water absorbed from the stool, leading to frequent watery motions.
It can be diagnosed with biopsies taken during a colonoscopy. It can be treated with a drug called Budesonide, a type of steroid, usually for three months, but sometimes it takes a few years to settle the symptoms.
If you do have IBs, there’s no one-size-fits-all treatment — it’s a question of trying different ones until you find something that works for you.
One relatively new idea that may help is the Low fodmap Diet. fodmaps are fermentable oligosaccharides, disaccharides, monosaccharides and polyls — short-chained carbohydrates or types of sugar found in a wide range of foods and drinks.
They cause problems because they are poorly absorbed in the small intestine and so enter the colon, where they are fermented by bacteria, causing bloating, wind and diarrhoea.
Most people are able to tolerate fodmaps — they will still have wind, but not pain as people in IBs have. By avoiding foods high in fodmaps (and, in susceptible individuals, milk and dairy products as well as bread, which also contains fodmaps), researchers have shown that diet can improve IBs symptoms in up to 73 per cent of cases.
The six fodmaps identified as the most likely to cause problems include fructans- oligosaccharides found in wheat, rye, onions, garlic and ar tic hokes;gl ac to-oligosaccherides found in legumes; lactose found in milk; fructose in honey, apples, pears, watermelon and mango; sorbitol found in apples, pears, stone fruits and sugar-free mints; and mannitol found in mushrooms, cauliflower and sugar-free mints.
research published last month in the journal Gastroenterology by King’s College London, which compared the low fodmap diet with a normal diet, has shown it’s an effective treatment for IBs.
Kevin Whelan, professor of dietetics at King’s College London, and the lead researcher, says: ‘A lot of the dietary advice given to IBs patients in the past about managing their symptoms through diet has been very hit and miss, and has been pretty much untested.
‘Our latest research has shown that following a low fodmap diet can resolve IBs symptoms in between 50 and 75 per cent of patients. It was particularly successful in helping to resolve flatulence, bloating and abdominal pain symptoms.
Professor Whelan said that in a follow-up study 12 months after patients tried the diet, they gradually reintroduced fodmap foods and the majority’s IBs symptoms did not return. ‘ We recommend people approach the diet in three stages; removing these foods from their diet, achieving resolution of symptoms and then slowly and systematically reintroducing certain foods one by one,’ says Professor Whelan.
But he stresses that because it’s a restrictive diet, people with IBs must get advice from a registered dietitian before starting it to ensure they will still get all the nutrients they need.
What’s Up With Your Gut?, by Jo Waters and Professor Julian Walters (hammer smith, £14.99).