Practitioner Question of the Month
Jason asks, “I understand that FODMAPs should be avoided in IBS, but what about resistant starch?”
Another good question. Let’s think about this from a 30,000 ft. perspective. To put it loosely, resistant starch is a type of prebiotic. If prebiotics have a negative impact on IBS (likely because they are feeding a microbiota that the immune system is already prone to attack), then does using a different form make sense? Not really. At least not theoretically. This being said, you could always have someone slowly and cautiously try resistant starch supplementation or to incorporate foods that are higher in resistant starch and see how they do. If there is any sign of regression, simply instruct the patient to stop. If you proceed slowly and start with a low dose you will mitigate any negative reactions.
But, why does Jason have this desire to try resistant starch? I think this is because there was massive hype surrounding resistant starch in certain circles on the internet. So there was hype, but if you look at the science behind the hype it was SUPER speculative; lots of animal model and petri dish studies…. Little to no human outcome study data (aka clinical trials). What do we see when we look at the clinical trials with resistant starch? Nothing impressive…. I review this here if you would like the details https://drruscio.com/dr-ruscios-book-preview-all-about-fiber/ . When we combine this with the fact that those with digestive conditions like IBS, IBD, and/or GERD/reflux have a significant amount of adverse reactions to prebiotics, we see a recommendation clearly emerge. Those with digestive conditions should be cautions with all prebiotics, including resistant starch.
One of the last podcasts that Robb Wolf and I recorded illustrated how this plays out in the real world. When resistant starch was first coming into vogue, Robb commented that he tried it and felt like it was really helping him. I didn’t say much as I didn’t want to burst his bubble, but I remember thinking ‘this isn’t going to end well’ – especially considering Robb has a history of Crohn’s (public information he has shared this on the podcast so I can disclose). Unsurprisingly, when we spoke again several months later Robb commented ‘doc I think resistant starch actually made me much worse’.
So what happened? Initial placebo effect which was then followed by an adverse reaction. Exactly what you would expect when you understand what the clinical data says and you avoid jumping on everyone else’s bandwagon (*remember the placebo effect accounts for 43% response on average and up to 91% at its highest*). These are things we as clinicians need to be immune to, because if patients can’t get competent advice from us, who can they get it from?
So in short, you can try it with anyone, but I would not recommend it with those with digestive conditions. Those without digestive conditions are most likely to experience a positive response. Prebiotics do have their clinical merit, which I will provide a detailed review on in my coming book, https://drruscio.com/gutbook/
I’d like to hear your thoughts or questions regarding any of the above information. Please leave comments or questions below – it might become our next practitioner question of the month.