#003 Patsy Catsos RD talks about IBS symptoms and the low FODMAP diet

Patsy Catsos is a registered dietitian specialised on the Low FODMAP Diet. Her special area of interest is in digestive health and she is a professional member of the Crohn’s and Colitis Foundation of America, the North American Society for the Study of Celiac Disease and the Academy of Nutrition and Dietetics. She is also the author of IBS-free at Last! and the cookbook series entitled Flavor without FODMAPs, as well as a blog editor at IBSfree.net.

Summary: Are you a good candidate for a low FODMAP diet? In this episode, Larah interviews registered dietitian Patsy Catsos as she explains what steps need to be taken to determine if a low FODMAP diet is right for you and also discusses some of the risks of following a low FODMAP if not under the supervision of a qualified dietitian.

 In this episode, you’ll learn:

  • How Patsy Catsos first discovered the low FODMAP diet.
  • What is Small Intestine Bacterial Overgrowth (SIBO)?
  • How SIBO affects IBS symptoms.
  • What are the standard measures for IBS to be taken before the low FODMAP diet?
  • How to determine a good candidate for the low FODMAP diet.
  • What happens to the person with IBS symptoms that eats a wrong food?
  • The prevalent percentage of IBS sufferers around the world.
  • Factors that contribute to IBS symptoms.
  • Risks on following the low FODMAP diet.
  • What is Inflammatory Bowel Disorder (IBD)?
  • Tips to follow in the low FODMAP diet.
  • How to replace garlic and onion in cooking.

Quote of this podcast episode is Patsy’s motto: “Learn more about FODMAPs and pass it on.”

Can’t listen to this episode right now? Read the transcript below!

Larah: Welcome to the low FODMAP diet and IBS podcast. I am very excited about today’s guest. My guest, Patsy Catsos, is a registered dietitian nutritionist, a FODMAP expert and author. She’s also the editor of the blog IBS-free.net. Patsy’s works focuses on digestive health, including Irritable Bowel Syndrome (IBS), gluten related disorders and Inflammatory Bowel Disease (IBD).

Patsy learned the term FODMAP back in 2007, well before most people knew anything about the subject of the diet. Patsy is a real pioneer of the low FODMAP diet. Her book, IBS-free At Last, which was first published in 2009, introduced thousands of IBS patients, as well as dietitians and physicians, to the FODMAP approach well before anyone in America knew what FODMAPs were.  Since then, Patsy has written two IBS-free FODMAP free cookbooks. She is very passionate about the low FODMAP diet and her motto is “Learn more about FODMAPs and pass it on.”

Larah: Hi Patsy.

Patsy: Hi. It’s so nice to be here with you today.

Larah: Thank you for accepting to be on my podcast. This is going to be so valuable for our listeners with IBS and following a low FODMAP diet. So, I would like to start by asking you, Patsy, if you could tell the listeners a little bit more about yourself and how you came across the low FODMAP diet?

Patsy: Sure. Well, as you mentioned, I’m a registered dietitian, but I’m also an ulcerative colitis sufferer, although I don’t suffer too much with it anymore. I was diagnosed with ulcerative colitis in about 1985 and so all these years, I’ve had a keen interest in anything to do with digestive health.

In 2007 I went to an event hosted by the Crohn’s and Colitis Foundation of America and the speaker there mentioned this term I’d never heard before, “FODMAPs”, and how helpful it might be to patients. I quickly tried to learn more about it and found just the barest bones of information in the published literature. Susan Shepherd and Peter Gibson had published a paper that described FODMAPs and the FODMAP approach and I started using it in my dietetics practice and immediately realised how helpful it was and how successful my patients were at managing their IBS symptoms. I turned those materials into a book eventually and things kind of went on from there.

Larah: Yeah, absolutely. I just ordered a copy of your book and I would recommend it to everyone because it’s so informative. It explains all the ins and outs about the symptoms and explains the diet. So, considering that you started so early, your knowledge now, so many years later, must be just incredible. Can you just explain a little bit more about when you see a patient that has suffered from these symptoms, can you recognise straight away that this could be IBS?

Patsy: Well, I leave the diagnosing of IBS to the patient’s physician. Ideally, when they come to me they’ve already had a thorough evaluation and have had some of the more medication management type diseases already ruled out and treated. So, hopefully they already have a good diagnosis of IBS.  I also like to have celiac disease ruled out before they start the diet, if possible, and if there is any indication that they might have small intestinal bacterial overgrowth, that should be diagnosed and treated first as well.

Assuming all of that has been taken care of before they meet with me, the first thing I do is make sure that they have tried the standard measures for IBS, because of the well-known benefits of fibre, for example. And because fibre does sometimes help people with IBS, I do feel like they should try the high fibre diet — eating regular meals, drinking enough fluids, getting enough exercise – all of those just good overall health habits first. And if they don’t help patients manage their IBS symptoms, then we move on to the low FODMAP diet. And frankly, almost all of my patients have already tried that before I see them. So, at our first visit, I try to figure out not whether they have IBS, but whether they’re a good candidate for a low FODMAP diet.

Larah: Okay, so how would you determine that they’re good candidates?

Patsy: In addition to a diagnosis that makes sense – so that would be like IBS, somebody with celiac disease, who still has symptoms even though they’re on a gluten-free diet, or maybe somebody with Crohn’s or colitis who has a lot of IBS-like symptoms, even though they’re in remission, perhaps; I need to see some evidence in their diet history that FODMAPs could be playing a role. You know, if they tell me that they already eating nothing but chicken and rice for the last three weeks and they’re still really symptomatic, there’s not really anywhere to go with the low FODMAP diet, is there? So, they either have to be currently consuming FODMAPs or they have to have a history of symptoms when they were consuming more FODMAPs, one or the other.

Larah: That’s a very good explanation. So, what do you think, what usually happens when someone suffering from IBS eats the wrong food?

Patsy: They’ll report symptoms of either diarrhoea, constipation, or both. They typically have excess gas and bloating, and frequently, abdominal pain. Those are the primary symptoms.

Larah: Yeah. That reminds me of very much of me a few years ago as well. So, how common is IBS? And is there any chance that some countries may have more IBS sufferers than other countries because of their diet and the lifestyle they have?

Patsy: Sure, there can definitely be diet and lifestyle factors. The prevalence of IBS worldwide is probably somewhere around 11% of the population. It really depends on how IBS was defined in the study that looks at the prevalence, so you see numbers all over the place from 1% to 40% depending on some of those factors. But in the United States and in countries with more or less similar populations and diets, it’s around 11%.

Larah: Yeah, I always thought around those figures or even up to 15%.

Patsy: Yes, or even up to 20%. It’s a condition that affects lots and lots of people.

Larah: Yeah, it is quite incredible. Also, considering the majority are going about their lives not really knowing that they even suffer from IBS.

Patsy: Yeah, true.

Larah: So, as a dietitian – we talked already a little bit about this before, but, if you can go into a bit more details – how would you determine that the FODMAP phase, so starting from the elimination diet, is right for that particular person?

Patsy: So, in my practice, I do a thorough nutrition assessment at the beginning of my relationship with each patient, so I need to hear in detail what their symptoms are and what all their different medical conditions are. It’s really important to me to protect people that might be at risk for an eating disorder from any harm, so I typically avoid going with any kind of a restricted diet in people who might not be able to do it safely, for any medical or psychological reason. So, it’s really kind of hard for people to do a restricted diet, also, if they aren’t really in full control of their food life. So, if there is an elderly person living in long-term care housing, or even sometimes a college student, who has to eat at the college or university cafeteria, it might be not good time for them to try the FODMAP elimination diet.

So, you need somebody who’s got a lot of control over their eating situation. They’re resilient and they are not suffering from any severe psychiatric problems. They have to be willing and they have to be able to do a dietary experiment. Some people are just not that flexible, so that’s another group that kind of falls from the way side. But those remaining people that are really good candidates, we start right away at the first visit with teaching them how to do the low FODMAP diet.

Larah: That’s very true because I remember when I was first told to follow a low FODMAP diet. I’m from Italian origins, so everything I ate was pretty much on that list. I so wanted to feel better that I said, “I’ve got to do this,” you know… I can understand that, depending on your age, maturity and your family situation, it might not just be as easy as just saying, “Okay, I’ll do everything it takes.” It may take longer for some people.

Patsy: Right.

Larah: So you touched already on this about some of the risks. Can you just go into a little more details about the risks for people following a FODMAP elimination diet?

Patsy: The main risk that everybody should be thinking about a little bit is that a lot of a high FODMAP foods are really good sources of food for the good bacteria in our guts and we don’t want to have any unintentional consequences from changing their food supply.

Some of the other risks that people talk about, I personally think, might be a little bit over blown. You hear people talk about the risk of poor nutrition on the diet and I really feel that there are lots of highly nutritious foods that are available to choose from on a low FODMAP diet. Problems develop when people have other dietary restrictions on top of the low FODMAP diet. So, it’s not really as much about low FODMAP, as it is about too many dietary restrictions in general. For example, if you have someone who won’t eat their vegetables, yes, there’s going to be at risk for not getting enough vitamins and fiber perhaps, but that’s more about their personal food choices.

I think it’s really tough for vegans to do a low FODMAP diet that provides all the essential nutrients. Other patients have various food sensitivities or other medical conditions that limit their diet. So, sometimes, when you pile several of these special dietary needs on top of each other, you can start getting into trouble, but for people that eat a varied diet and are willing to eat a varied low FODMAP diet, I think that risk is small.

Larah: Yeah, that’s great information. Thank you, Patsy.

Patsy: Yeah.

Larah: So what happens when I explain to people what my condition is, they seem to understand that I cannot have gluten because straight away I say, “I know I can’t have this.. it has got wheat,” and they say, “Oh yeah, I don’t have gluten either because, you know, I’m sensitive to gluten and all that.” I think a lot of people have this misconception,    first of all that they shouldn’t have gluten, even though they may not be celiac or sensitive to gluten, and then that the low FODMAP diet, they should be gluten-free as well. Can you just explain the difference for our listeners?

Patsy: Sure. Well, I tell my patients that it’s really a coincidence that the grains, wheat barley and rye contain both gluten and FODMAPs. Gluten is the protein in those grains and FODMAPs, in that case, are the fibres in those grains. So even though a lot of gluten-free food works nicely on the diet because they are low in FODMAPs, it’s not really the gluten we’re after.

Larah: That’s right. It’s not the gluten, so do you think that people think it’s the gluten, even though they might not have IBS or anything like that, in fact, is it just because it’s more like a trend now to go gluten-free for some of them maybe?

Patsy: For a small percentage, I’m sure. I see sort of a self-selected group of people that really do have health problems related to their ingestion of these things, but once in a while I meet somebody who’s on a gluten-free diet and really has no idea why they’re doing it. They’re doing it because it’s a trend or a fad or they heard that it was good for them. But you know, more often, my patients anyway are doing it because they don’t feel well and they find it helps their GI symptoms.

If you have a lot of other symptoms that you might attribute to gluten – say you have a rash or suffer from migraine headaches – and if those other sorts of things seem to be related to eating gluten, they’re more likely to be, I think, a true gluten sensitivity. But if all the symptoms are related to the gut, then I believe it’s more likely that it’s the FODMAPs and those gluten grains that are making a difference.

Larah: Yeah, I agree with you. You mentioned at the beginning about the different digestive disorders that could benefit from a low FODMAP diet and you mentioned your digestive disorders as well. Could you go into a bit more detail about these digestive disorders and how they might be able to benefit from the low FODMAP diet?

Patsy: Sure. Well, Inflammatory Bowel Disease (IBD) is different from IBS. Those are conditions affecting the gastrointestinal tract where there is actually a visible inflammation that can be seen when the patient has endoscopy. The biopsy specimens that are taken during those procedures have characteristic changes and there are chronic diseases that kind of come and go over the person’s lifetime. They usually have to be managed with medications, but there are science emerging in the science now and the literature that a low FODMAP diet can actually help manage these diseases.  And, up until now, I’d kind of been doing it because it made common sense, not to add fuel to the fire of somebody’s IBD symptoms to be consuming a lot of high FODMAP fluids for example, but now there is a starting to be a little evidence for that approach with IBD and I think we have a lot more to learn now, because, you know, just as with people with IBS, we don’t really know what the long term consequences of this diet and what the change might be.

Larah: Yeah, that’s right, so more studies need to be done to support that.

Patsy: Yup, but because the symptoms are so close, you know. They both involve some of the same disturbed bowel habits. I think that it makes sense to try a low FODMAP diet and see if it helps.

Larah: Yeah. That would be great really, if it helped for more issues.

Patsy: Another condition that is sort of an emerging diagnosis is Small Intestinal Bacterial Overgrowth or SIBO. That happens when some of the good bacteria that should be in your large intestine, somehow make their way up into the small intestine. and they can ferment the sugars and short chain fibres that fall under that FODMAP umbrella and cause a lot of distress in the small intestine. We really have no proof of any kind about what the best diet is to use for that condition, but low FODMAP diet makes as much sense as anything. To take away the favourite foods of those gut bacteria to keep them at low level. I think, makes a lot of sense, and that’s the approach I use in my practice until we know more.

Larah: It seems like a lot of people that suffer from IBS also suffer from SIBO.

Patsy: Yeah.

Larah: It’s that a coincidence or…?

Patsy: Well, that’s probably been happening for years, but nobody really recognised that a lot of patients with IBS actually do have bacterial overgrowth in their small intestine, so I think it’s more than just a coincidence. I think it’s the reason for symptoms for some people. I think it will be kind of interesting over the years to see how the definition of IBS changes. Maybe that percentage that we talked about will shrink of people that have IBS as described as functional symptoms that don’t have a medical explanation. So, as we can explain more of them with SIBO and treat them, that percentage of people with IBS will probably shrink.

Larah: Yes, as you said it’s about really eliminating anything else that could possibly be wrong with you until they say “Okay, it’s not this; it’s not cancer; it’s not a heart problem; it’s not an infection; there’s nothing wrong with your organs. It must be IBS”.

Patsy: Right.

Larah: So, pretty much. Would you have any tips for the listeners on the low FODMAP diet? Just how to follow, when to follow it and possibly, also, why they should see a dietitian rather than try and follow it by themselves really?

Patsy: That’s a really good question. So, I always say, the low FODMAP diet or a FODMAP elimination diet is more than just a list of high and low FODMAP foods. It’s actually a fairly tricky process and so patients benefit from having a real strategy and a plan that they can put into action. I guess that’s why I wrote IBS-free at Last, and that’s why I think most patients can benefit from working with a dietitian who can provide that strategy and plan.

The book, I guess, is a good backup if there’s no trained dietitian available. It is kind of a specialty interest, so you wouldn’t really expect a dietitian who specializes in diabetes management or some other problems to be able to help. I recommend trying to get with a trained GI dietitian. Don’t try to change everything at once. Choose a period of time to really focus on diet and try not to change at the same time, your medications and your laxatives and your probiotics and your other supplements. Just focus on diet.

We usually start by eliminating all the high FODMAP foods for a period of time. Then, if you got a really good response to the diet, then you re-introduce them, one FODMAP at a time. And again, you have to really focus, keep your eye on the ball and try to focus on just introducing one new FODMAP, while everything else in your diet stays the same. Monitor your symptoms and then see what happens after that.

Larah: Yeah, because it’s not a one size fits all, so you really have to work with someone that can really monitor your symptoms according to what you’ve been eating and all that.

Patsy: That’s right.

Larah: So, are you a unique case in the United States in terms of all the knowledge you have on the low FODMAP diet, or is that expanding more and more and there are a lot more dietitians now in the United States with that knowledge?

Patsy: It’s definitely expanding every day. At the beginning, yes, I was probably the only person that was using this approach at one time in the United States, but over the years, that situation has really changed. I’ve presented workshops and seminars and 90-minute talks to dietitians all over the country, sometimes by myself, sometimes with my friend and colleague, Kate Scarlata. And, of course, other people now are learning independently of me, but there’s so many more published articles that we can read to learn about FODMAPs. There are now five different nutrient composition papers that have been published by the researchers at Monash University. We have a lot more history, I guess, at this time with using the diet. More physicians are learning about the diet. In fact, I just attended Digestive Disease Week which is a big conference; I think there were probably about 15,000 gastroenterologists there and FODMAPs was a big topic, so gastroenterologists are definitely hearing a lot about this diet, many of them are really on board with a diet-first approach for IBS now, and that’s really exciting.

Larah: That’s fantastic news. I’m so grateful that I was put on this diet and had a change of life. It’s incredible. This is why I’m trying to really share the message as much as I can, so your motto could become my motto too.

Patsy: Yes. You know I think when patients like you go back to their doctors and report how helpful the approach has been and how much better they’re feeling, they do really care about that and I think that motivates the physicians to look into the diet a little bit more and to recommend it more often to other patients. That is something that we can all do to help each other is make sure our doctors know about this approach.

Larah: Yeah, absolutely. And I was lucky to find, finally, a GP that listened to me and after I explained everything that was wrong with me, he wanted to really get to the bottom of it because all the other doctors I saw before, they were just pretty much dismissing me or, you know, maybe would give me some tablets for indigestion.

So you were mentioning before your book, IBS-free At Last. Would you like to say a few words about that book and any other books that you written or co-written?

Patsy: Sure. So that is the title of my original book. I think I have a copy. Oh, you have a copy of it right there too.

Larah: Yeah.

Patsy: I’m actually working on a third edition of this book which will be published early next year. I think the title is going to be a little different. I’m going with a traditional publisher this time instead of self-publishing and they have a different title in mind, but I’m sure you’ll be able to find the author of IBS-free at Last, if you search for that. And this book is a step-by-step program on how to do an elimination diet and FODMAP re-introduction on your own or working with a dietitian. You know, a lot of dietitians use this book as their primary teaching tool. The new edition will have also 50 recipes in it.

Larah: Great.

Patsy: The one you’re holding in your hand just had a few basic recipes. And then, since that one was published in 2012, I believe it was, that second edition, I have put out a couple of cookbooks. One of them is called – the most recent one – IBS-free Recipes For the Whole Family and those recipes were developed by Lisa Rothstein who is a mom and really focused on family-friendly recipes. She’s the person in her family with IBS, but she wants to prepare delicious meals that her kids will enjoy, and her husband, family and friends will enjoy, so that was the motivation for that book.

Also, we worked with Karen Warman who’s a pediatric dietitian at Boston Children’s Hospital. You know, there’s been very little work done to test the use of the diet with children, and throughout the book, we focus a lot on what I think are really appropriate cautions about using this diet safely with children. We don’t want to solve one problem and create another one. It’s important not to create food fear and anxiety with kids and I strongly feel that if you are interested in using this idea with children, probably, as much as possible, the less said, the better. The parents and the family can just do their parental thing and adjust what groceries are purchased, what recipes are prepared to try to help the children without really getting them too…

Larah: …too worried about the food that they cannot eat.

Patsy: Right. Thank you. It’s hard for the kids to, I think, understand well. Regular milk is bad food this week, but then the next week, you’re asking them to try it again to see how they tolerate it. So we counsel parents in the book to stay away from the idea of good foods and bad foods and just to quietly carry out the program as much as they can on the children’s behalf.

And my other cookbook is called Flavor without FODMAPs and the recipes in that book tend to be a little bit smaller – maybe more of like 4 servings per person — and really focus on using all the tricks in the book to make low FODMAP food taste really great. Some of the usual kitchen staples like onions, garlic and wheat-based products are off limits during the elimination phase, so it takes a little practice for people to adjust to that.

Larah: Yeah. How do you personally replace the garlic and onion in your cooking?

Patsy: Garlic is easy because garlic-infused oil makes a great substitute for garlic in terms of flavor. Onion’s a little trickier because not only do you have to replace the flavor of the onion, but you also have the volume of the onion that you have to replace, so I’ll typically replace the volume with low FODMAP vegetables like, maybe, chopped red pepper, or a fennel bulb – things that will bulk it up a little bit and replace the flavor with either chives or the green parts of scallions.

Larah: Those are good tips, yes. Yeah, I make use of a lot of garlic-infused oils and also onion-infused oils and I got adjusted perfectly because in my cooking, being Italian, there was a lot of onion and a lot of garlic before. So, not anymore, by replacing the taste.

That’s fantastic. Thank you so much for all the information that you provided us with. If our listeners would like to get in touch with you, could you share your website or your Facebook page…anything?

Patsy: Sure. I only see patients right here in Maine where I’m a licensed dietitian, so I can’t help people as far as giving medical advice unless they’re my patient. But if you want to keep in touch about FODMAPs, I would really welcome that, and my website is www.ibsfree.net. I’m really active on twitter and my twitter handle is @catsosIBSfreeRD. I also have a nice Pinterest board that would be particularly of interest to people in the  US, because it has pictures of grocery items that I think are probably low FODMAP. Most of them have not been laboratory tested, so they’re put on my board based on my reading of the listed ingredients. Oh, and I have my Facebook page for my book to just interact with people on the topic of IBS and FODMAPs and that is IBS–Free, I think, is the handle there.

Larah: Okay.

Patsy: So those are the main ways that I keep in touch with my readers.

Larah: Yeah, and not to worry if you haven’t got it all because I’m going to put those into the show notes.

Patsy: Oh, great.

Larah: So they’ll be linking to the show notes with all the different address.

Well, thank you so so much, Patsy, for being on my podcast. I so appreciate it.

Patsy: You’re very welcome, Larah.

Larah: Thank you. Was there anything else that we haven’t covered that you think we should have mentioned?

Patsy: Well I think we were pretty thorough. I’ll just leave parting words that I encourage everyone to try really work out the diet that works best for them and not get wrapped up in accumulating dietary restrictions that other people think might be a good idea for those with IBS. You know, you need to test every idea for yourself and only limit your diet in ways that are essential to managing your symptoms.

Larah: Very true words. I agree with you. That’s great. Thank you so much, Patsy.

Patsy: You’re welcome. Good bye.

Larah: Goodbye.

I hope you have enjoyed this episode with registered dietitian nutritionist, Patsy Catsos. Before saying goodbye, I would like to ask you a big favor. If you have enjoyed my podcast, can you please go on iTunes and just leave a review for the podcast? That would really, really help. If you would like to read the show notes for this episode with all the links, please visit my website at www.lowfodmapdiets.com/3. I wish you all the best for now and take good care. Good bye.

Links and resources mentioned in this episode:

 Patsy’s website: IBS Free At Last!

 Patsy’s books as an author and co-author: 

Links to Patsy’ s social medias:


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About Larah

I have been suffering from Irritable Bowel Syndrome for many years, but it took a longtime to get a diagnosis, since then I have been following a low FODMAP diet, which has changed my life for the better. This is my story and experience with IBS and the low FODMAP diet.