Dr. Mark Pimentel on fiber, the low-FODMAP diet , and what to eat during SIBO treatment

Who are you???”

I had just walked into Dr. Mark Pimentel’s office for my first appointment when his nurse looked up and said that.

At first I thought she mistook me for a celebrity (flattering, but we were in Los Angeles at Cedars-Sinai hospital after all!).

But actually, she was just surprised because Dr. Pimentel hardly ever takes on new patients anymore.

Between researching, teaching, running his own laboratory and directing the Medically Associated Science and Technology (MAST) Program, and treating his existing patients (who have some of the most complex GI conditions in the world) he’s a pretty busy guy.

I was very, very lucky to be able to get an appointment.

That first appointment was life-changing – and every time I’ve encountered Dr. Pimentel since then has equally enlightening.

If you’ve ever heard him speak, you know that Dr. Pimentel has a way of speaking that is direct, concise, and simple to understand – even when he’s talking about crazy-complex concepts.

Today, I’m going to share some of what Dr. Pimentel taught me about fiber, the low-FODMAP diet, and what to eat during Small Intestine Bacterial Overgrowth (SIBO) treatment at one of our last sit-downs.

And if what you learn in this blog post is helpful, make sure you check out Dr. Pimentel’s Masterclass.

Fiber and SIBO

Shivan Sarna: People are wondering about SIBO and fiber. How do we get enough?

Dr. Mark Pimentel: The bigger question is, what is enough fiber and do we really need fiber.

A lot of people have been eating fiber because they think it’s healthy and then, now, everybody’s going Paleo and going to even keto diets, and all these diets seem to be even healthier than high-carb diets.

I don’t know that you need a lot of fiber in your diet. I think fiber can be helpful in terms of if you’re a normal person and you want a nice, smooth bowel movement and maybe fiber to help the beneficial bacteria of the colon, have more food.

For SIBO, fiber is no good either. It’s just a lot of fermentation, a lot of gas, and a lot of trouble.

The Low-FODMAP Diet Long Term

SS: Let’s talk about the low FODMAP diet and how we don’t want to allegedly be on it for a really long term because it reduces the variation of the microbiome. Do you agree with that? Should we be thinking about that?

MP: Fiber, yes, leads to more diversity in the colon. But as I’ve said before, if you put fiber in the gastrointestinal tract like beans, it’s going to take a lot longer for cleaning waves to recover. It’s going to take a lot of time for the fiber to evacuate from the small intestine leaving more fermentables there for gas, bloating, and distention.

But, the low-FODMAP diet is not healthy long term, and even those who discover and continue to discuss low-FODMAP diet have suggested that. Bill Chey from Hanover, Michigan presented at the ACG Meeting the first study looking at how bad is it to be on low-FODMAP [long term].

After three months, you start to see micronutrient deficiencies. It is not a long-term solution to IBS, which is what it’s touted for. SIBO was kind of the extension of it.

Now, it can be helpful. So, I kind of tell people, “If you don’t eat any food at all, your SIBO will disappear,” because the bacteria can get no food – but that’s not a solution.

The more you restrict calories, the more better your SIBO will feel. But then you’re going to cause harm to yourself, so you’ve got to find that best practice for you, which is why we sort of developed the low-fermentation diet.

We developed that in 2001 or something, and it’s meant to be 100% recommended daily allowance of all mineral and vitamins, so that you don’t get the deficiencies, and yet calorie-restrictive enough to help SIBO.

What To Eat During SIBO Treatment

SS: When you’re taking Rifaximin or treatment [for SIBO], you say, “Eat whatever you want because we want the bacteria having a party,” so that they’re out and about, so the medicine can do its job of killing it. Is that right?

MP: Yes. [But] I don’t tell people to go and eat like a gallon of Haagen-Dazs ice cream every day to make their SIBO go away!

You want to be a little more open with your diet during SIBO treatment, that’s what I suggest. [But if you go too far] what ends up happening is you’ll feel worse on the treatment thinking that the antibiotic is making it worse, when it’s actually the diet.

I just tell people, just go about your normal business, eat what you normally eat while you’re taking the treatment. You don’t need to hyper activate the bacteria.

SS: Nor would you suggest like really being super strict on a low-fermentation diet?

MP: I would suggest not to be on a low-FODMAP diet while you’re taking the antibiotics because you are restricting calories to a great extent and bacteria will tend to be more resistive to antibiotics in hibernation.

The Complex Becomes Digestible

Anytime I have a conversation with Dr. Pimentel, things that I thought were so complex – like what to eat during treatment – become crystal clear.

He has a true gift for teaching from a patient’s perspective!

That’s why I’m overjoyed to give you access to Dr. Pimentel’s research updates and talks with our community!

The SIBO SOS™ Mission

My mission at SIBO SOS™ is to connect as many IBS and SIBO patients as possible with the very best doctors in the world.

I have spent more money than I want to think about trying to find out what was “wrong with me.” SIBO is an expensive condition and takes so much time and energy.

Let’s acknowledge that right here and now!

But I also want you to know, I’m in it with you.

So while we can’t all see Dr. Pimentel in person, there is still a way we can all learn from him directly: it’s our Masterclasses!

Myself and the entire team at SIBO SOS™ work diligently to make these programs as accessible and affordable as possible.

Information and Inspiration.. Both are needed to get well.

(I have heard from some people that there is “too much information.” I have felt that way myself at times. My goal is never to overwhelm you, but it is also my calling to share as much as I can! 

Do you have any suggestions for overcoming the “overwhelm” that comes with a condition like SIBO? Please share with us in the comments.)

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21 thoughts on “Dr. Mark Pimentel on fiber, the low-FODMAP diet , and what to eat during SIBO treatment”

  1. Hey Shivan! Thank you so much for all your great SIBO+ hosting!
    To be sure I’m getting this correct, Dr. Pimentel suggests following up after the SIBO treatment with their low fermentation diet, as opposed to one of the other SIBO diets; (plus a prokinetic if warranted).

    1. Thank you for sharing your conversation with Dr. Pimentel regarding diet during treatment. I am starting my third week of rifaximin and AliMed and hoping this will help. I’ve tried various treatments in the past, and nothing has worked. I am now on five years with IMO.

  2. Is it OK to have chia seeds and flex seeds with your food? I’m asking because these seeds have fiber and the low fermentation diet doesnt recommend fiber-rich foods.
    Thanks so much,

  3. Hi i have been on low food map diet and had antibiotic for three rout and herbal treatment my symptom is getting worse and i dont know how to get ride of my sibo

    1. Hi Mary
      I just found out that I had to cut off all histamine foods to calm down symptoms. Also have suspicion if oxalates are a problem. Have you tried antifungals for SIFO?

  4. I’m sorry, but this endless cycle of experts recommending very restrictive diets and then hearing you say don’t restrict too much is making a very difficult situation even worse. That is why I have stopped paying to hear all these speakers. We all just want to feel better. I do get a couple of pearls of information from these talks, but since everyone says something different, how do we know who to listen do? May the experts all need to meet and come up with some consensus about how to best treat SIBO. I am very frustrated.

    1. Hi Nina, We hear you…unfortunately, every body is different. We all have a different microbiome and have unique experiences that contribute to the complexity of healing from any chronic condition. Each expert has contributed in some way to relieving symptoms for me personally as I reached new obstacles in my search. The best we can do is support you. Did you know that the SOS of SIBO SOS™ stands for Save OurSelves? We truly believe that to heal, we have to educate ourselves which includes a bit of experimentation to determine what works best for us. We share a lot of great pearls of wisdom from each Masterclass in the blogs (click BLOG at the top of this page), in our SIBO SOS™ Community Facebook group, and our Youtube channel, click here to subscribe. I wish you all the best. ~Shivan and the SIBO SOS™ Team

  5. I do appreciate this info ,,, BUT , I have been on a low FODMAP diet for about 2 years ! I have attempted to introduce new foods & probiotics; even began eating a little clean ( ? ) pork , and recent tests ( nuteval and OATS ) reveal lots of deficiencies & imbalances . ( micronutrients and some macro ) I
    I do eat wild caught sockeye salmon , nuts , ghee, and blueberries ( only fruit I eat ) and veggies . ( non -starchy ) No alcohol , no dairy , no grains , except occasional white rice , no coffee, no sugar , no yeast etc. Along with trying to not eat much at all & doing intermittent fasting , etc . How does one possibly re- build the gut , expand the diet & be free of bloat , constipation , and the stress that accompanies trying to heal body , mind & spirit ! Also , am taking enzymes , rotating herbal anti – microbials ,,, and blah blah …
    Cannot find a way to turn this around … hmm introducing the lowfermentation diet – but, I cannot eat more than 60 % of the diet ! Just don’t know a way out of this rabbit hole !

    1. Hi Arianna!

      I so sympathize with you. Dealing with SIBO can feel like an endless cycle of stress and restriction. It sounds like you’re in a rut where you’re not making much progress and could benefit from trying something new. One thing I experienced personally was that the MORE I restricted, the fewer and fewer foods I tolerated.

      Here’s something Dr. Michael Ruscio said at the IBS & SIBO SOS™ Summit that really resonated with me: “We don’t want to have anyone on a restrictive diet longer than they have to be. This is a general principle. We should be working to use these diets to gain awareness, figure out what foods work, and what foods don’t work, and then, ultimately, be trying to broaden to the widest diet possible. That’s very important.
      And for some people, the main thing that’s making them feel sick is the fact that they haven’t tried to push to a broader diet, and they keep going more narrow, more narrow, more narrow. And they haven’t pushed back outwards. Sometimes, that simple change of just trying to loosen up your grip or your rules on the diet can actually be very healing and helpful for people.”

    2. I just want to say I’m sorry you are going through this too. Your comment hits hard and I have been struggling with the Will to keep living because I’m so tired of starving or being in agony everyday.
      Thank you for sharing.

      1. Cyndi Athmanathan

        Hi Drea,
        Please reach out for support there are answers and support groups for SIBO and the underlying conditions. We see so many who have found relief, so please reach out. And if you do not already have a professional working with you on your case please start that process. You are not alone.

  6. Unless I missed something there, I only see fiber being used during treatment. What about longterm chronic cases that are not cured by sibo treatment? What do we eat then? No fiber? I think dysbiosis is going to be a factor in these cases and microbiome a big factor.

    1. Hy Lou – I think Dr. Pimentel is saying he hasn’t seen a large benefit of adding in fiber supplements or eating a specifically high fiber diet across the board – and that especially for people with SIBO, fiber can be a problem.

      I also don’t think he is saying either eat high fiber or eat NO fiber (which is basically impossible) but rather that you may not need to focus on getting a specific amount of fiber (like a number of grams every day) – just eat what you can tolerate.

  7. My approach to overcoming the “whelm” is to restrict where I’m getting information from to only the most reputable sources, and to choose one pathway to explore at a time and really focus on it. For example, I get most of my information from Dr. Seibecker, Dr. Pimentel, and Dr. Hawrelak. Now I’m focussing on probiotics and the micro biome so registered for Dr. Hawrelak’s master class which was really informative. Now I’ve registered for his “Meet Your Biome” class and have order a UBiome test kit. I reason that probiotics are way cheaper than other treatments so if this works, it’s something I can afford to maintain. If it doesn’t work, I’ll try a different pathway.

  8. Hi Shivan,

    I am confused, I purchased the entire Masterclass Series and is Dr. Siebecker’s SIBO Solved part of that or is it a separate purchase?

    Can someone please check and let me know what I have purchased so far as my SIBO FIBRO FOG is really bad!

    Thanks and God Bless,
    Cindy Collins

    1. Hi Cynthia!

      Sorry for any confusion. You can see everything you’ve purchased by going to members.sibosos.com and logging in.

      If you’re still not sure (or have trouble logging in) go ahead and email us at in**@si*****.com and we’ll get you taken care of!

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