Have your IBS symptoms gotten worse during the lockdown? Stress and anxiety can be contributing factors to an IBS flare-up, as well as eating the wrong foods. If you are interested in which foods to avoid for IBS or which foods trigger IBS, then a low FODMAP diet might be of interest to you.
If you regularly struggle with bloating, distention, stomach cramps, constipation and/or diarrhoea, then you will know it’s no fun and not something you’d wish on your worst enemy. You may have been through rigorous testing and finally been diagnosed by your GP with Irritable Bowel Syndrome, and sent home with “unfortunately there’s nothing much we can do”.
So you’re left with this diagnosis and wondering what you can do to recover. You have been told that ‘diet and lifestyle management’ might improve your quality of life, but you don't know where to start.
Irritable Bowel Syndrome (IBS) is a condition, which is very common in the population, with women being more susceptible, and it is thought that up to 1 in 8 people will experience IBS. The cause of IBS is incompletely understood (1), however, stressful life events or gastrointestinal infections are considered possible causes, and the condition is generally exacerbated during stressful periods. Recent studies are showing that anxiety and depression can also be closely linked to IBS (2).
IBS should not be confused with Inflammatory Bowel Disease (IBD), which includes Crohn’s disease and Ulcerative Colitis. As the name suggests, IBD is a condition characterised by inflammation in the gut, and is much more severe than IBS.
If you have been diagnosed with IBS, a low FODMAP diet may be recommended by your nutritionist, as a short-term strategy to reduce your symptoms, and to help discover which foods may be contributing to your health issues. This is not a ‘one size fits all’ approach, but rather a way to help personalise your diet for longer-term suitability.
The low FODMAP diet is a short-term dietary strategy first developed by researchers (specifically Dr. Sue Shepherd in 1999) at Monash University in Melbourne, Australia (my home town). Their website is a really useful resource for IBS sufferers, and it is continuously being updated with the latest research (3).
If you decide to embark on the diet, I recommend downloading their app as a way of supporting you through your low FODMAP journey (but please only do so with the help of a suitably qualified health professional).
So what are FODMAP’s?
FODMAP (Fermentable Oligo-, Di-, Mono-saccharides and Polyols) carbohydrates are specific carbohydrates and fibres found in certain grains, fruits, vegetables, legumes, milk products, and processed foods. They include lactose, fructose, fructans, polyols, and galactans. FODMAP foods can be poorly tolerated and not absorbed as they should be in some people. Therefore, they pass through the small intestine and into the large intestine, where they feed the gut bacteria, causing fermentation and resulting gas, constipation or diarrhoea, or both.
Simply put, FODMAP’s are sugars commonly found in everyday foods.
FODMAP foods include:
Excess fructose: honey, apples, mango, pears, watermelon, high fructose corn syrup, agave syrup, dried fruit, fruit juice.
Fructans: artichokes, asparagus, beetroot, Brussels sprouts, cabbage, aubergine, fennel, garlic, onions, leek, lettuce, mushrooms, wheat, rye, pistachio nuts, cashew nuts.
Lactose: milk, ice cream, custard, milk powder, yogurt, soft cheeses, goat milk.
Galactans: legumes – beans, chickpeas, lentils
Polyols: apple, apricot, avocado, blackberry, cherry, nectarine, pear, plum, prune, mushroom, xylitol, sorbitol, mannitol.
* The low FODMAP diet should not be followed for more than 2 – 6 weeks at a time, and it should always be followed with the guidance of an experienced health professional.
Foods you can eat include:
Meat, poultry, and fish
Carrots, peppers, courgettes, bok choy, kale, chard, ginger, squash, potato, sweet potato, green beans, tomatoes, spinach, cucumber, celery, olives, rocket, lettuce.
Broccoli stalks are high FODMAP and florets are low, so therefore can be enjoyed in moderation.
Cabbage and Brussels sprouts although high FODMAP may be tolerated in small amounts.
Bananas, blueberries, kiwi fruit, strawberries, raspberries, grapes, canteloupe, pineapple, oranges, lemons, limes.
Walnuts, almonds, pecans, hazelnuts (small amounts)
Lactose-free milk, hard cheeses, butter, lactose-free yoghurt or plain Greek yoghurt
Oats, quinoa, chia seeds (in moderation), rice, buckwheat.
After the initial restricted 2 - 6-week period, and when symptoms have settled, FODMAP foods can be slowly introduced back into the diet, one at a time. This helps to determine which foods are causing you problems.
Some vegetables and fruit are low in FODMAPs when consumed in moderation, but become high FODMAP in larger quantities. The Monash University FODMAP app is very helpful in determining which foods you can eat and in what quantities. They have a traffic light rating system to indicate whether a food is high, moderate, or low in FODMAPs, and which quantities are safe to eat.
This video shows how FODMAP foods can trigger gut symptoms in people with IBS:
The low FODMAP diet can be particularly tricky to navigate, and that is one reason why you need the help of a trained IBS nutritionist or other health professional. Other conditions such as intestinal permeability (4) and Small Intestinal Bacterial Overgrowth (SIBO) may also need to be investigated (5).
And following a strict low FODMAP diet for longer than 6 weeks can be detrimental to the health of your microbiome. This is because FODMAP foods contain many important nutrients, particularly fibre, polyphenols, and vitamins, which are necessary for a healthy microbiota. A good supply of fibre from our diet provides the growth of short-chain fatty acids, which are beneficial to our gut microbes.
A low FODMAP diet doesn’t necessarily work for everyone with IBS. Hydrogen breath testing and microbiome stool analysis can help to determine key imbalances in the gut, which may be causing or contributing to your symptoms.
The causes of IBS can be multifactorial, and that is why it is important to work with an experienced health professional. Stress is also a well known contributing factor, therefore stress management plays a vital role in getting your symptoms under control.
It is crucial that you get diagnosed by your GP first, as they will need to rule out more sever conditions such as Coeliac disease, or inflammatory bowel disease (IBD) such as Colitis and Crohn’s disease.
Important points: In summary
Always get a proper diagnosis by your GP and to rule out other more serious health conditions such as coeliac disease, Crohn’s disease, and Ulcerative Colitis.
Only follow a low FODMAP diet under the guidance of an experienced nutritionist or other health professional.
Only follow the initial stage of the low FODMAP diet for a maximum of 6 weeks, so as not to risk damaging the health of the microbiota.
Helen Ross is a registered nutritionist, specialising in gut health and IBS support. If you'd like to know more about eating for a healthy gut, and/or how to keep your gut healthy, book in for a FREE call here to discover how she can help you.
Helen offers a virtual (online) clinic and local IBS support and nutritional therapy services to the Bridport, Dorchester, Weymouth, Poole, Bournemouth, and East Devon areas.
Ford, A. C. (2020) ‘Commentary: estimating the prevalence of IBS globally—past, present and future’, Alimentary Pharmacology and Therapeutics. doi: 10.1111/apt.15508.
Sibelli, A. et al. (2016) 'A systematic review with meta-analysis of the role of anxiety and depression in irritable bowel syndrome onset', Psychological Medicine. doi: 10.1017/S0033291716001987.
The Low FODMAP Diet: Monash University. Found at: https://www.monashfodmap.com/
Bischoff et al. (2014) ‘Intestinal permeability - a new target for disease prevention and therapy’, BMC Gastroenterology. doi: 10.1186/s12876-014-0189-7.
Small Intestinal Bacterial Overgrowth website by Dr Allison Siebecker found at http://www.siboinfo.com