IBS and the FODMAP diet

Affecting an estimated 1 in 7 people at some stage in their lives, irritable bowel syndrome (IBS) is staggeringly common, especially among women. The symptoms can be uncomfortable – stomach cramps, bloating, constipation and diarrhea. There are a number of treatments a GP may suggest for those who experience IBS. This includes diet and lifestyle changes as well as medications and probiotics. Your GP may recommend you undertake a low-FODMAP diet if you don’t respond to these treatments.

FODMAP, which stands for Fermentable Oligo-, Di-, Monosaccharides and Polyols, are types of carbohydrates that can cause ongoing gut symptoms for people suffering from IBS. The low-FODMAP diet is not a weight-loss diet. It may do more harm than good, unless you’ve been diagnosed with IBS.

The low-FODMAP diet works by cutting out these carbohydrates and reintroducing them slowly, with the guidance of a registered dietician. It’s really important that you see a dietician before you start the low-FODMAP diet. This will ensure you stay healthy, get all the nutrients you need, prevent your IBS symptoms from worsening and that you fully benefit from the diet. A dietician will also help you to understand the foods you can and can’t tolerate, and what your threshold level is (how much you can eat).

Which foods are in the FODMAP diet?

The low-FODMAP diet can be difficult given the number of foods that contain the carbohydrates in question. FODMAPs are divided into four groups:

  • Oligosaccharides are made up of wheat, rye and legumes, such as broad, butter and kidney beans, plus a large number of fruits and vegetables, including garlic and onions.
  • Disaccharides are foods where lactose is the main carbohydrate such as milk, yoghurt and soft cheese.
  • Monosaccharides are foods where the main carbohydrate is fructose. These include figs and mangoes as well as honey and agave syrup.
  • Polyols are sugar alcohols that sweeten foods like pears, blackberries, avocados and mushrooms. It also includes the sweeteners added to many foods including sugar-free gum.

Given how restrictive this diet is, it’s not meant as a permanent solution for those with IBS. Restricting high FODMAP foods for short periods of time and reintroducing them carefully with the help of a dietician can help you ascertain which foods bring on symptoms. Fortunately both stomach pain and bloating significantly decrease with a low-FODMAP diet. Studies show that it can improve the quality of life for many IBS sufferers.

Once you start a low-FODMAP diet with the help of a nutritionist, you’ll be able to increase the variety of foods you can include in your diet. The end result will be a modified low-FODMAP diet, unique to your own body’s needs. However, the low-FODMAP diet doesn’t work for everyone. It can take up to six months to reach the end of the process. During this time, it’s important to maintain a strict low-FODMAP diet until you reach the modified low-FODMAP phase.

FODMAPs and Gut Health

The foods we eat to encourage diverse good bacteria in our gut. Fermented foods that contain friendly bacteria to our guts (probiotics) and fibre-rich foods that feed the good bacteria in our guts (prebiotics) can often be high in FODMAPs. Yoghurt, kefir, kimchi, kombucha and kamut sourdough are often very rich in FODMAPs. You have to be very careful when discovering your body’s tolerances. Rather than trying every gut-friendly drink out there at once, talk to your dietician about introducing them individually and gradually.

Apply the same caution to prebiotics too. Here at Liz Earle Wellbeing, we’re champions of high fibre for gut health, but for sufferers of IBS the rules can be a little different. Research suggests that fermentable fibres can cause irritation for some people with IBS. Stick to fresh leafy greens like kale and spinach to avoid feeling bloated and uncomfortable.

Fortunately, there are some probiotic supplements that are suitable for IBS. Look for strains that have been scientifically proven to help with the condition. Check the labels, as many add prebiotic fibres, such as inulin, that may flare up your symptoms.

For more information on gut health, FODMAPs and IBS have a look at Liz’s e-guide ‘A Flatter Happier Tum’

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