Everything I thought I knew about sIgA was wrong! - Aspire Natural Health

Everything I thought I knew about sIgA was wrong!

Every once in a while, an idea comes along that throws your mental models topsy turvey.

Recently while reading a book called The Wild Life of Our Bodies by Rob Dunn (good book, definitely worth a read), I came upon a section that did just that.

I closed the book, turned to look at my wife (she was driving at the time) and just said, “wow!”

The Barbed Wire of the Gut

Secretory IgA is an antibody that lines the surface of our digestive tract (and lungs, urinary tract, and vagina) and for the longest time I’ve always described it as “the barbed wire of the guts”.

IgA is the most common antibody in the body, accounting for about 75% of all the antibodies that we make.  In the gut it’s made by B cells and then passed over to the cells that line the digestive tract which secrete it onto their surface (thus secretory IgA).

My old understanding was that it’s primary purpose was defensive.  This line of secreted IgA on the surface of these cells served to protect them from bad bacteria, viruses and other “nasty stuff”.  When I do stool testing, about 80% of people with gut problems have low or very low levels of secretory IgA.  Thus their guts are not able to fight off the dysbiosis (or messed up bacteria).

But wait, there’s more!
But it seems my understanding was not quite right.

From the Wild life of Our Bodies “…Studies since the 1970s had noted that the bacteria the IgA attacked had a receptor…for IgA…When the IgA attacked those bacteria, they did so through that door.  What, though, were the bacteria doing with a door for the very antibodies whose goal it was to attack and expel them from the body?…if…[the] body was, through the production of IgA, trying to get rid of or otherwise control these bacteria, it was doing a really bad job.  If the bacteria were trying to avoid the IgA antibodies, they were similarly ineffective…”

Hrm, I didn’t know that.  Of course the bacteria he’s talking about are our “good guys” like Lactobacillus and Bifidobacterium (among others).  Maybe I’ve been missing something.

“…the IgA antibodies…help the bacteria by providing a kind of scaffolding with which they can link together to form biofilms…the human body…was producing compounds to help the bacteria adhere…instead of fighting the bacteria, [it was] helping some of them stay put…eventually…[scientists were] able to show in the lab that when IgA was added to biofilms, they formed faster and grew thicker.  Bacteria were nearly twice as likely to stick to human cells when IgA was present.  When an enzyme was used to break down the IgA, the biofilms fell apart…IgA, it now seemed evident, performs the primary function of helping bacteria…gut bacteria grow fifteen times as fast when IgA is present than when it is absent.”

Whoa!  <KABOOM!>  That popping sound was my mind exploding!

So it looks like sIgA’s primary job isn’t direct defense (killing off bad guys) but “mothering” – encouraging and stimulating the growth of good bacteria who of course provide a huge part of our defense system.  And then, only secondarily, acting like “barbed wire”.

Thinking back through patients, this clicked.  I have some patients who seem to stubbornly refuse to bring up their levels of good bacteria.  We eradicate their bad bacteria, yeasts and parasites (if they have them), but despite probiotic, prebiotics and fermented food consumption their levels of good bacteria just don’t want to come up.  And universally their sIgA levels remain significantly depressed.

So it looks like another, often overlooked, focus in gut restoration needs to be boosting sIgA levels back to healthy levels.

And might at least some of these people have a congenital (born with = genetic) IgA deficiency?  A simple blood test can suggest whether this is true (measuring total serum IgA).  If that test comes back quite low you may have hit the “bad genetics lottery” and may always have trouble maintaining a good gut flora.

Another puzzle piece in gut health, clicks into place.  That’s why I always keep learning.

For more on which probiotics to take, click HERE.


At Aspire Natural Health we are experts at helping people suffering with digestive issues and autoimmunity.

Are you looking for help?

Email us at info@aspirenaturalhealth.com or call us at 425-202-7849.  The first step of our process is to see if we’re a good fit for one another.  If we are, we’ll talk about next steps.  If not, that’s okay, and we’ll do our best to help you find the right person.

Everything is no-obligation and no-pressure, so you don’t have to worry.  You have nothing to lose!

Call us at 425-202-7849 or email us info@aspirenaturalhealth.com now

Another interesting post:

Fermented foods vs supplements for gut healing

Photo attribution:  https://bit.ly/1nCbnLY

This Post Has 17 Comments

  1. Andy says:

    How do we raise the IGA count in the body? Is this possible?

  2. Danna says:


  3. Leonardo says:

    Hi, your article is great! I have gut dysbiosis, my secretory Iga levels are extremely low and now I understand why I cannot bring up my levels of good bacteria and heal the dysbiosis. But the question is: What should I do to boost my sIga back to healthy levels??

  4. JBR says:

    Interesting, I’ve just had a comprehensive stool analysis showing raised SIGA levels along with raised Lysozome ( and a prior blood test with raised oesonophils), it showed negative on parasites but I’ve had some strange mild itchy sensations and could swear something is moving about down there. Could the raised levels be contributing to my sensations?

    • Tim Gerstmar says:

      Hi James,
      The raised secretory IgA says that your immune system is being stimulated by something. Parasites are one cause, so is bacterial or fungal overgrowths. Itchy sensations could be parasites (stool tests are great but parasites can be hard to find), but could be irritation or inflammation of the skin.

      Hope that helps!

      Dr. Tim Gerstmar

  5. Victor says:

    Hi! Great article, thank you. I’m a father of 3 y.o. severely autistic kid. I keep him on special diet, no grains, low meat, mostly raw veggies and fruits (organic only) for over a year now. I’m also doing comprehensive stool tests, trying to validate his recovery. For the first 11 month on thgis diet his Secretory IgA was very low, suddenly it skyrocketed from 340 to 6900 ug/g within 3 month. Now I hope to see his disbiosis to disappear

    • Tim Gerstmar says:

      Hi Victor,
      I applaud you for trying to help your child. Seeing the secretory IgA go from low to high like that is a very promising change that I like to see. Keep up the good work! And if you’re interested in getting some assistance, I’ve worked with quite a lot of similar cases, please give us a call at 425-202-7849 or send us an email at info@aspirenaturalhealth.com

      Dr. Tim Gerstmar

  6. Aj says:

    Great article! I have very low SIgA, among other gut issues. The reason I pursued testing is because I have developed a severe intolerance to salicylates and I was trying to find the source of the issue. My problem is that many of the supplements I would normally rely on to heal my gut, I am reactive to them (throat swells, nose gets congested, HR rises, mouth burns and more). I’m looking for guidance on a safe effective place to start to heal my gut. My SIgA was 25, taken from a comprehensive stool test.

    • Tim Gerstmar says:

      Hey AJ,
      Thanks for the comment. Salicylate intolerance is often a by-product of a damaged gut, and I’ve seen a good number of cases resolve as the person heals, so have hope!

      I can’t tell you what your next steps should be without doing a thorough evaluation of you and your situation. It sounds like a lot of the cookie-cutter answers don’t work for you, so you’ll need someone with experience and expertise to help figure things out with you.

      If you’re interested, give us a call at 425-202-7849 or an email at info@aspirenaturalhealth.com. There’s no pressure, and no obligation, if we’re the right fit for you, we’ll let you know, and if we’re not, we’ll also let you know and see if we can help you find the right practitioner.

      Dr. Tim Gerstmar

  7. Greg says:

    How can you raise levels if you have selective iga deficiency? Can you raise them if you have a level of 0. Also, what does it mean if you have a high IGM level (around 700?) Thanks

    • Tim Gerstmar says:

      Hi Greg,
      If you truly have a genetic selective IgA deficiency and do not produce IgA then I know of no way that you can stimulate your system to produce it. If I were you I would consider outside supplementation with something like colostrum that might supply immune factors and has been helpful for many people with gut issues.

      IgM is typically raised with a new infection. If you’re not dealing with some current issues, my thoughts would be that your system is trying to compensate for a lack of IgA.

      Would you like to have a thorough evaluation done to get some answers?

      Please give us a call at 425-202-7849 or send us an email at info@aspirenaturalhealth.com

      Dr. Tim Gerstmar

  8. Maryam says:


    Ive been told I have raised IGA levels and I’m trying to figure out how to lower them…I’ve recently started having allergic reactions to things I wasn’t previously allergic to e.g mouthwash, magnesium oil.
    Skin is very itchy. GP saying there’s nothing I can do and to take antihistamines.

    Any tips on how I can figure out what’s causing this and how to lower it?

    • Tim Gerstmar says:

      Hi Maryam,
      I’m afraid without knowing much more about your situation, I can’t say. Something, or a number of things, are irritating your immune system and creating more sensitivities to things. The itching is just an immune reaction. Have you had your gut properly tested for your gut bacteria? Have you done an elimination diet? Many things that could be done depending on what you’ve already tried.

      If you’d like some help, contact us at info@aspirenaturalhealth.com, and we’ll have a chat to see if we’re a good fit and can help.

      Dr. Tim Gerstmar

      Specialty Integrative Care. Experts at Treating Digestive issues and Autoimmunity

  9. C says:

    My last S-IGA was 1380. We just lol, burned through another $200 of the best probiotics money can buy, they won’t help as much if your bad bacteria have put up inpenetratable biofilm. I had better luck shooting for 5-10 trillion CFU numbers vs. billions or 100’s of billions of CFU. After many, many years of suffering you start to learn more through both experimentation, health talks, etc.

    • Tim Gerstmar says:

      Hi C,
      Yes, probiotics can really help a lot of people, but you need the right one, and the right amount, and yes, things like biofilms can be an issue. It’s important we all be educated in our health, and definitely some experimentation is needed to find the right fit for us as opposed to what’s worked for other people.

      Thanks for stopping by!

      Dr. Tim Gerstmar

Leave A Reply