The new way to tackle IBS


There might be plenty of wacko diets around, but despite its weird name the Low FODMAP Diet isn't one of them. It's a way of eating that's helped change the way doctors treat the abdominal pain, bloating, constipation and diarrhoea that can go with irritable bowel syndrome.

FODMAPs is shorthand for the tongue twisting 'fermentable oligosaccharides, disaccharides, monosaccharides and polyols'. These are fermentable carbohydrates found naturally in vegetables, fruit, grains, nuts, seeds, dairy food, as well as some additives, that for some people are a pain in the gut. Cauliflower, onions, garlic, apricots,  chickpeas and yoghurt are just a few of the otherwise healthy foods that can cause problems for some sensitive  people. These foods all contain types of carbs that we don't digest and when they arrive in the large bowel undigested they ferment and create gas.

For most of us this is a  non-event, but for the 15 per cent of people with IBS this gas can trigger bloating, discomfort and pain - pain that's occasionally bad enough to send people dashing to Accident and Emergency, says dietitian Dr Sue Shepherd of La Trobe University's Department of Dietetics and Human Nutrition who first identified these carbs as culprits in IBS. The cause of many IBS symptoms is the genetic lottery that's supplied some of us with hypersensitive nerve endings in the lining of gut, she explains

"When there's a lot of gas it puts pressure on the gut and the nerve endings of the bowel and this can make the brain overreact and register pain. These fermentable carbohydrates can also change how quickly the bowel works - in susceptible people they can lead to constipation and diarrhoea or a combination of both," she says.

The trick to taming these symptoms is having fewer fermentable carbohydrates in the diet - research at both Monash University and London's Kings College Hospital has found that this works for around 75 per cent of people with IBS. While a low FODMAP diet puts some healthy fibre-rich foods off limits, it doesn't mean sacrificing fibre, says Shepherd, the author of 'Low FODMAP Recipes', a new cookbook to help people with IBS make meals that minimise the gassy effects of FODMAPS.

Although wheat, rye, barley and many vegetables including peas and mushrooms can cause problems, there's still brown rice, quinoa, oats and buckwheat, as well as plenty of other vegetables. Spelt, a form of wheat, is also a problem but some breads made with spelt flour (Ancient Grains and Healthybake, for instance) are low in FODMAPs. This is because fructans - one of these indigestible carbs - gets broken down in the manufacturing process, she adds.

Low FODMAP eating can be harder on vegans for whom high FODMAP beans and lentils are a good source of protein, iron and zinc. "But you don't have to cut legumes out entirely - everyone with IBS has a different threshold of how much fermentation their gut can handle before the nerve endings start screaming,"  says Shepherd.

The trick is to be scrupulous about avoiding other high FODMAP foods so you can tolerate some legumes. It's best to eat just small amounts of legumes, ideally spread throughout the day - two small serves of legumes over lunch and dinner is easier on a sensitive gut than one generous serve at dinner, for instance. It's also fine to eat tofu and tempeh - although made from soy beans, they're not usually a problem because they're pre-fermented, she adds.  Small amounts of nuts are okay - except for pistachios and cashews.

As for boosting the flavour of meals without using onion and garlic, Shepherd suggest garlic infused olive oil. "It gives a great garlic flavour without the bloat, and instead of onion you can use chives or the green part of spring onions or shallots," she says.

Low FODMAP Diet New Zealand Article

FODMAP - Guidelines