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Did you miss this webinar?  Over 450 of your colleagues attended this timely and cutting-edge topic which is in such widespread use in clinical practice for IBS.

As promised we have pulled the questions from the chat pod and our presenter Dr. Caroline Tuck has graciously provided the answers.  Here is what you wanted to know:


Q-Are probiotics in pill form as effective as those that are refrigerated?

Q-There are several strains of probiotics: is there a product name recommendation?

A-Many research studies have investigated the role of probiotics, with mixed results. At this stage, there is insufficient evidence to recommend a specific strain of probiotic and/or the form it comes in. The following research article may be helpful: McKenzie YA, Thompson J, Gulia P, Lomer MCE. British Dietetic Association systematic review of systematic reviews and evidence-based practice guidelines for the use of probiotics in the management of irritable bowel syndrome in adults (2016 update). J Hum Nutr Diet. 2016;29(5):576–92.


Q-Are no added sugar/plain yogurt and kefir part of Low FODMAP diet?

Q-According to the Monash University Smartphone app, Kefir and Yoghurt are high in lactose content. You may use trial and error with the patient to test their individual tolerance.

Q-In the phone app it has different types of soy milk, some are red and some are green.  Tempeh is green.  Boiled soybeans are red.  Firm tofu is green.  Silken tofu is red.  TVP is red.  Could you please explain the differences in why some of these soy products are ok and others are not recommended?

A-The FODMAP content of foods is altered by both the ingredients and the food processing techniques used. For example, some soy milks are made with the whole soy bean and are high FODMAP, whilst some soy milks are made with the soy protein, resulting in a low FODMAP content. This blog post written by Monash University may be helpful.

A-The following research article may also be helpful: Tuck CJ, Ly E, Bogatyrev A, Costetsou I, Gibson PR, Barrett JS, et al. Fermentable short chain carbohydrate (FODMAPs) content of common plant-based foods and processed foods suitable for vegetarian- and vegan-based eating patterns. J Hum Nutr Diet. 2018

Q-What about the sprouted grains?

A-Sprouted grains were shown to have a reduced FODMAP content in a recent research article. Individual tolerance testing with each patient would be recommended.

Q-Would garlic powder be a good alternative?

A-Garlic powder would be high FODMAP, and therefore not suitable for the low FODMAP diet. 

Q-Does fiber or psyllium increase water in the bowel and make symptoms worse?

A-The effect of fiber can be variable on the patient and their symptom types. The following article is an excellent resource on this topic: Eswaran S, Muir J, Chey WD. Fiber and functional gastrointestinal disorders. Am J Gastroenterol. 2013;108(5):718-27.

SIBO (Small intestinal bacterial overgrowth)

Q-Do you find or recommend that patients be tested for SBIO? I know someone who tried FODMAP for a while with mild results and then was tested for this and after antibiotics had complete resolution of her IBS symptoms.

A-Unfortunately, there is limited research in the area of SIBO, largely because there are large limitations in the techniques used to try to diagnose SIBO. Techniques such as breath testing have high false positive and/or false negative rates. The topic of SIBO is debated amongst the medical and scientific community. Hopefully with more research, in the future we will understand more about the role of SIBO. 

Q-Can you speak of the efficacy of the FODMAP diet on lessening symptoms of SIBO?

A-As per the question above, due to difficulties in diagnosis of SIBO it has been poorly studied. No studies have investigated the efficacy of the low FODMAP diet on SIBO. 


Q-The Monash Uni low fodmap diet app is $9.00 in the google play store.  Unfortunately, most of my patients will not be able to afford this.  Any other suggested apps?

A-Other apps will not update with new foods / research, hence the Monash University low FODMAP diet app is recommended. If patients are unable to afford the app, then other resources such as education materials may be the best option.

IBD (Inflammatory bowel disease)

Q-Would you recommend this for people with IBD?

A-There are a few studies in IBD patients – mainly done in those who are in remission but having ongoing IBS-type symptoms. The studies to date show that it can be helpful in this patient group. There is no evidence for the diet in patients with active IBD. 

Following a low-FODMAP

Q-How well are people able to stick to the low FODMAP diet?

A-Clinical practice suggests that patients are generally able to be compliant with the dietary recommendations. Keep in mind, that it is a ‘low’ not a ‘no’ FODMAP diet, so small discrepancies are not an issue. Additionally,  the diet can be individualized to the patient, as discussed in the webinar, there are strategies to try to improve compliance.

Q-How do you decide to trial the low FODMAP diet for IBS versus other diets (e.g. SCD, etc.)?

A-Unfortunately, evidence is limited for many dietary therapies. Currently, the low FODMAP diet has the best evidence for efficacy to help manage symptoms of IBS. The following review article discusses the evidence for different diets. Tuck, C. J., and S. J. Vanner. “Dietary therapies for functional bowel symptoms: Recent advances, challenges, and future directions.” Neurogastroenterology & Motility (2017).

Q-Are there an increased risk of malnutrition or micronutrient deficiencies with people on FODMAP diet?

A-Studies to date have shown variability on the effects of the low FODMAP diet on nutritional adequacy. Some studies have shown reductions in fibre, calcium, and iron, whilst others have suggested an intake of these have been maintained. Differences may be due to study design or cultural differences at baseline. Importantly dietitians should encourage substitution of low FODMAP alternatives to help maintain nutritional adequacy. This topic was recently reviewed here: Staudacher HM, Kurien M, Whelan K. Nutritional implications of dietary interventions for managing gastrointestinal disorders. Curr. 2017.

Q-Does that mean you re-challenge one food in each subgroup, or just pick one subgroup to focus on at a time?

A-Suggest one challenge at a time, that uses one food to represent tolerance to a particular subgroup e.g. honey to test tolerance to excess fructose.

Q-A little confused about the “daily or second daily” descriptions

A-This is in reference to how often the patient might trial the food i.e. consuming the food every day or on every second day. The table with this information is from the following article which provides more information on how to re-challenge: Tuck, C., & Barrett, J. (2017). Re‐challenging FODMAPs: the low FODMAP diet phase two. Journal of gastroenterology and hepatology, 32(S1), 11-15.

 QWould the challenge be the same food in the same amount for 3 days in a row? Or just one food and wait 3-4 days?

A-Usually it is recommended the same food is used for 3 days for each challenge.

Q-If you react poorly to one food in a subgroup, does that necessarily mean you will likely react to most foods in the subgroup?

A-Usually, tolerance to one food can represent tolerance to all foods in that group. This is generally the case for lactose, excess fructose and sugar polyols. See question below for variation for fructan and galacto-oligosaccharides.

Q-Is it possible to tolerate one fructan (onion/garlic) and not another? (wheat)

A-Clinical practice suggests that with some FODMAP subgroups e.g. fructans and galacto-oligosaccharides, tolerance can vary within subgroups. If a patient eats multiple food types in this group it may be worthwhile including multiple challenges e.g. onion, garlic, and wheat all challenged on separate occasions.

Q-How long do you recommend spacing out between challenges?

A-Suggest having 1-2 day ‘break’ in between challenges to avoid any cross-over of symptoms during challenges. If symptoms occur on any particular re-challenge, then ask the patient to wait until symptoms have returned to normal before starting the next challenge. 

Q-How long should you wait before bringing them back for a rechallenge?

A-Suggest patients come back for review ~8 weeks after educated on re-challenge, although you may modify this depending on the patient. 

Q-There are a lot of questions around re-challenge. It may be helpful to read the following article which discusses how to implement the re-challenge process in detail. Tuck, C., & Barrett, J. (2017). Re‐challenging FODMAPs: the low FODMAP diet phase two. Journal of gastroenterology and hepatology, 32(S1), 11-15.

Additional questions

Q-I had a doctor recommend low FODMAP for a patient with severe dermatitis, is that appropriate?

A-As far as I am aware, there are no research studies looking at the use of the low FODMAP diet in dermatitis.

Q-Do you know of any connection between Lectins and FODMAP metabolism?

A-As far as I am aware, no studies have looked this.

Q-Where do you purchase alpha-galactosidase enzyme? OTC or Rx? Dosage?

A-‘Beano’ is one brand of the alpha-galactosidase, we used 300 units in the study – same as packet instructions. Another brand name is ‘Vitacost-gas enzyme’. These can be purchased over the counter in the USA.

Q-Is there an age where the diet should not be trialed for example 90 yo?

A-Be cautious of using the diet in older adults – might be a good time to just modify a few foods rather than the full low FODMAP diet. Always keep ‘red flags’ in mind and refer back to the doctor if red flags are present.

This blog was posted by Robin Allen, a member of OneOp (MFLN) Nutrition and Wellness team that aims to support the development of professionals working with military families.  Find out more about the OneOp Nutrition and Wellness concentration on our website on Facebookon Twitter, and LinkedIn.