Gut health

The Perfect IBS Diet (Part 2)

Your perfect IBS diet will be unique to you and may even change over time. As mentioned in Part 1, there are many different diets that have been studied and found to be of benefit in IBS but little agreement as to the best diet (because the best diet will vary from person to person)1,4. So how do you go about finding your perfect IBS solution? Start with the “prime suspects” – foods that are known to be the most common triggers for IBS symptoms.

Cutting out the prime suspects 

IBS Research shows that most IBS sufferers report worsening symptoms after consuming some common food and drinks5,6:

  • wheat and gluten grains
  • milk
  • yogurt and cheese
  • onion, and garlic
  • spicy foods, sugar (and sweeteners)
  • caffeine and alcohol

By cutting out these likely trigger foods for 3-4 weeks, you allow your gut to take a rest, to heal and for your symptoms to subside. At the end of the elimination period you will begin to systematically reintroduce these foods whilst keeping a close eye on your symptoms so as to identify which of the eliminated foods are a problem for you. The first week can be hard, you may have been eating some of these foods for many years and your body will have to adjust to a change in diet. You may experience cravings, or your symptoms may temporarily get worse before they get better.

Keeping track

Even during the elimination phase, it is important to keep a food and symptom diary as this will help you to identify whether there are other trigger foods that cause problems for you specifically. If you identify a new problem food, you should eliminate this food too.

Some foods to watch out for are7:

  • beans and legumes
  • high carbohydrate foods
  • citrus fruits
  • eggs
  • nuts
  • chocolate
  • tea

High fibre foods (e.g., Jerusalem artichoke, asparagus, beetroot, Brussels sprouts, broccoli, cabbage, chicory root, fennel, oat bran, okra) may also cause problems, depending on the quantity eaten. Some gluten-free breads contain fibres like inulin derived from chicory or Jerusalem artichoke and can catch out the unwary: read the labels! When you start to reintroduce foods, this food and symptom diary will be even more important.

Reintroduction

When your symptoms have reduced (after about 4 weeks of elimination) and appear to be stable you can begin to systematically reintroduce the foods you cut out over the past 4 weeks, starting with onions and garlic, then dairy foods, and then wheat and gluten grains. Cautious reintroduction of your personal triggers, spicy foods, caffeine, alcohol and sugars might be considered after this. You’ll use your food and symptom diary to record everything you eat, and you’ll note down any symptoms you experience. If it is apparent that a reintroduced food worsens your symptoms, you should once again eliminate that food. By the end of the process, you should have a clear picture of which foods are the culprits in your own individual health issues.

Tips for success

  • Drink plenty of water
  • Plan your meals ahead of time
  • Always read food labels before you buy
  • Always shop with a list
  • Check menus online or call ahead when eating out to check if there will be food which you can safely eat
  • Make sure you always have suitable foods handy when you are on the go, in case of sudden hunger pangs, or if you are running late for meals.
  • Getting overly hungry can result in making poor food choices.
  • Avoid eating large meals as these can also trigger IBS symptoms

Encouraging healing

At the same time as removing possible problem foods, it is well worth using other techniques to aid gut healing including: Chewing well Encouraging good stomach acid and proper digestion Restoring the balance of the gut bacteria What if your symptoms do not resolve during the elimination phase? Some people will need to exclude more foods. If you are finding it hard to identify your unique triggers despite having cut out the prime suspects, it may be that you would benefit from a more comprehensive elimination phase,1,8,9 which we explain in our article on the low “FODMAPs” diet.

  1. McKenzie YA, Bowyer RK, Leach H, et al. British Dietetic Association systematic review and evidence-based practice guidelines for the dietary management of irritable bowel syndrome in adults (2016 update). J Hum Nutr Diet. 2016;29(5):549-575. doi:10.1111/jhn.12385
  2. Rej A, Aziz I, Tornblom H, Sanders DS, Simrén M. The role of diet in irritable bowel syndrome: implications for dietary advice. J Intern Med. 2019;286(5):490-502. doi:10.1111/joim.12966
  3. Werlang ME, Palmer WC, Lacy BE. Irritable bowel syndrome and dietary interventions. Gastroenterol Hepatol. 2019;15(1):16-26.
  4. Cuomo R, Andreozzi P, Zito FP, Passananti V, De Carlo G, Sarnelli G. Irritable bowel syndrome and food interaction. World J Gastroenterol. 2014;20(27):8837-8845. doi:10.3748/wjg.v20.i27.8837
  5. Harper A, Naghibi MM, Garcha D. The Role of Bacteria, Probiotics and Diet in Irritable Bowel Syndrome. Foods (Basel, Switzerland). 2018;7(2). doi:10.3390/foods7020013
  6. Brown BI. Does Irritable Bowel Syndrome Exist? Identifiable and Treatable Causes of Associated Symptoms Suggest It May Not. Gastrointest Disord. 2019;1(3):314-340. doi:10.3390/gidisord1030027
  7. Capili B, Anastasi JK, Chang M. Addressing the Role of Food in Irritable Bowel Syndrome Symptom Management. J Nurse Pract. 2016;12(5):324-329. doi:10.1016/j.nurpra.2015.12.007
  8. Barrett JS. How to institute the low-FODMAP diet. J Gastroenterol Hepatol. 2017;32:8-10. doi:10.1111/jgh.13686
  9. Tuck C, Barrett J. Re-challenging FODMAPs: the low FODMAP diet phase two. J Gastroenterol Hepatol. 2017;32:11-15. doi:10.1111/jgh.13687

Caroline Rees
Caroline Rees

Caroline is a a Registered Nutritional Therapist and member of the British Association for Nutrition and Lifestyle Medicine. She holds a master's level postgraduate diploma in Nutritional Therapy and a PhD in Immunology.