Chris Kresser: They have different functions. Guar gum soluble fiber that is bifidogenic and is microbiotic accessible, meaning it should feed the beneficial gut bacteria. It’s not very well tolerated by most patients. The partially hydrolyzed guar gum is better tolerated because it’s already kind of pre-broken down. Slippery elm is mucilaginous herb that has a kind of soothing coating action on the GI tract including the stomach but other parts in the intestines as well, and it can be helpful if there is any kind of ulceration and structural problems in the colon, bleeding, etc. I think they both have a role. One thing to note is that slippery elm is a FODMAP, so patients with sensitivity to FODMAPs may not be able to tolerate that very well, whereas partially hydrolyzed guar gum is a soluble fiber.