Somewhere between 70-90% of your immune system lives in your gut.
That’s exactly why I built Tummy Soothe around ImmunoLin, and why it’s the one supplement I’d put in almost everyone’s protocol.
What is ImmunoLin?
ImmunoLin® is a serum-derived bovine immunoglobulin/protein isolate (SBI). It’s a protein-based dietary supplement, over 90% protein, containing more than 50% immunoglobulins that supports digestive function and a healthy mucosal immune system. Researchers have identified over 180 individual proteins inside it, mostly IgG, with smaller amounts of IgM and IgA.
In plain terms: it binds to the antigens your gut is reacting to, so your immune system has less to fight.
Here’s the mechanism. When SBI binds an antigen, it forms a complex too large to cross the gut lining. Instead of that antigen slipping through a compromised barrier and triggering an immune response, it stays in the digestive tract and exits through normal digestion. A 2015 in vitro study (Detzel, et al.) confirmed exactly this: the antigen-binding action of SBI prevented those antigens from crossing intestinal cells at all.
Here are 3 reasons it earned a permanent spot in my protocol:
- It binds to microbial antigens, including lipopolysaccharides (LPS), which limits how much gets absorbed into your system.
- It supports intestinal homeostasis: the balance your gut needs to digest food, absorb nutrients, and keep your immune response steady.
- There are over 45 human clinical trials behind it, covering IBS, SIBO, Celiac, and more.
“I can say without a doubt that my digestive system is much happier since I started including this in my protocol!”
— Sonia P.
Is ImmunoLin safe?
ImmunoLin has FDA GRAS status (Generally Recognized As Safe), granted in December 2008.
Across published clinical studies and chart reviews, it’s been used by over 530 people, at doses ranging from 5g to 20g a day, for as little as one day and as long as 24 months. No known side effects.
If you have a beef allergy, skip this one. That’s the only population I’d steer clear of. Everyone else, keep reading.
How I get it in: Tummy Soothe
Tummy Soothe is built around ImmunoLin, and it’s the #1 supplement I think the Gutsy community should be taking. Here’s exactly what’s in each serving:
- 2.5g of ImmunoLin® SBI to support gut health and a healthy gut immune system*
- 1.1g of IgG to support a normal immune response*
- 1g of N-acetyl-D-glucosamine (NAG) to support normal immune function and gut health*
- Dairy-free
For context: the recommended daily dose of ImmunoLin on its own is 1,000-2,000mg. A healthy gut naturally produces somewhere around 3,000-5,000mg of immunoglobulins a day, so Tummy Soothe’s 2.5g serving sits right in that supportive range.
One thing worth knowing: ImmunoLin at 5g is a prescription medical food, used by gastroenterologists nationwide for IBS, IBD, and HIV enteropathy.
Around 2018, Entera Health worked with the FDA to lower the therapeutic dosing so this immunoglobulin therapy could be more widely accessible.
That’s why I built it into Tummy Soothe.
Tummy Soothe
✔ Supports gut health
✔ Supports healthy intestinal cells
✔ Supports gut immune function
✔ Supports GI barrier integrity
GET TUMMY SOOTHE HEREUse code AGUTSYGIRL at checkout to save 15%.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
SBI binding agents
If any of these are a concern for you, Tummy Soothe is worth a look. SBI binds to:
| Aflatoxin B2 | Peptidoglycan |
| Aflatoxin G1 | Flagellin |
| C. albicans lysate | Zymosan |
| C. albicans Als3 protein | C-di-AMP |
| H. pylori CagA protein | CpG |
| Cytolethal distending toxin subunit A | MDP |
| Cytolethal distending toxin subunit C | Gliadin |
| Shiga-like toxin type 1 | E. coli |
| Lipopolysaccharide (LPS) | Staphylococcus |
| C. difficile Toxin A & B | Klebsiella pneumoniae |
| Salmonella Typhimurium | Serratia marcescens |
Source: What Does SBI Bind To? (PDF)
Top questions, answered
Does this help with IBS-C, not just IBS-D?
Yes. Constipation is a motility and gut barrier problem, often driven by inflammatory antigens. ImmunoLin binds and removes those antigens. If you’re starting with IBS-C, go slower: half a dose of Tummy Soothe twice daily for 10 days, then half a dose once daily, alongside a motility protocol (fiber, water, movement).
What if I have a meat sensitivity?
A meat sensitivity and a beef allergy are two different things. The concern is specifically a beef allergy, which isn’t common. If you’re unsure, check with your provider before starting.
Will this interfere with my probiotic?
No. Research shows SBI doesn’t slow the growth of probiotic or commensal bacteria, and human studies found no meaningful shift in gut microbiota after taking it. It’s safe to take alongside your daily probiotic.
Go deeper: episode 105 with Brian Kaufman
Click HERE to save this article + episode for later.
Episode 105: Show notes
Episode 105 on the ‘A Gutsy Girl‘ podcast: ImmunoLin as the Star Ingredient in Tummy Soothe, My Obsession Explained is all about, you guessed it, ImmunoLin and why we need it for overall gut and immune health.
This article started as Episode 105 on the A Gutsy Girl podcast, where I sat down with Brian Kaufman to talk through exactly why ImmunoLin earned a spot in my own protocol.
In the episode, we cover:
- Who is Brian Kaufman?
- What is an antibody, and why does it matter?
- Why take an antibody like ImmunoLin if you already take probiotics?
- How ImmunoLin works, and who should be taking it
- The difference between colostrum and a serum-based antibody like ImmunoLin
- What the clinical trial results show
- Whether this is safe for all populations
- How long until you see results
- Whether it can be taken alongside other ingredients or therapies
Subscribe Today:
Listen to the Episode HERE | Apple Podcasts | Spotify | iHeart Radio
Most of the research above, including the safety data and the GRAS designation, comes from the ImmunoLin white paper FAQ built specifically for Tummy Soothe. Worth the full read if you want the studies behind every claim on this page.
About Brian Kaufman, RN: Brian is a decorated Army veteran and GI nurse with over 15 years of experience in direct patient care and medical sales, focused on digestive health and infectious disease. He’s the Vice President of Global Business Development for Proliant Health & Biologicals, the company behind ImmunoLin.
Rome wasn’t built in a night, and neither was your microbiome.
Brian Kaufman
Wrap-Up
As always, a huge goal for this show is to connect with even more people. Feel free to send an email to our team at podcast@agutsygirl.com. We want to hear questions, comments, show ideas, etc.
Did you enjoy this episode? Please drop a comment below or leave a review on Apple Podcasts.
If you liked this podcast episode on the ImmunoLin, you might also enjoy:
- Best Immune Boosting Herbs (and the Gut-Immune Connection)
- Interesting Facts About the Immune System {Plus 13 Science Backed Ways to Boost Your Immune System}
- Immune Boosting Gut Health Support
Grab Tummy Soothe today and save 15% with code AGUTSYGIRL at checkout. SHOP HERE
Xox,
SKH
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