SIgA Testing and Treatment

Nutritionist Micki Rose follows up Dr Albert Robbins' recent SIgA article with some practical advice

I read with interest the article from Dr Albert Robbins about SIgA recently and thought you might like to know how to find out if your own levels are low, and what you can do about it if they are.

In practice, if I find a person is not able to fight off infections, candida or resolve allergies, SIgA is one of the first factors I look at. It gives a good picture of how strong the body’s mucosal immunity is and, if you like, how much ‘fight’ that person has to complete the job.

In this follow-up piece, we will recap a bit about SIgA, then look specifically at testing and treatment.

SIgA: Allergy, Candida, Infection And Leaky Gut

Secretory IgA (SIgA) is the main immunoglobulin in mucus secretions. The intestinal cells produce about 2-3g of SIgA every day and production tends to peak in childhood and start to decline after about sixty years old.

Many people think of mucus as being in the nose and sinuses, but actually there is much more in the gut. A sticky lining of mucus is our first-line defence against gastro-intestinal pathogens like bacteria, food proteins, parasites, fungi, toxins and viruses. 

Simply put, the SIgA antibodies prevent micro-organisms, food proteins and carcinogens from binding to the surface of absorptive cells. Effectively, they attach themselves to invading nasties, trap them in mucus and stop them from going anywhere. They then neutralise any damaging toxins given off and help ensure the invaders are shown the door via faeces. Clever little system.

The antibodies also 'tag' foods as acceptable to the body and this suggests why low SIgA levels can be the key to developing and progressive food allergy and intolerance.

Leaky gut is also related since, if levels are low, repair of mucosal tissues can be compromised.


SIgA shouldn’t be confused with IgA, a related antibody that is commonly checked via blood tests along with IgE and IgG in immunity and allergy problems. Secretory IgA is quite independent of blood IgA levels and, just because one seems OK, it doesn’t mean the other is, so it’s always worth checking SIgA if IgA blood tests look normal and vice versa.

SIgA can be measured in different ways, including stool and saliva. Levels can turn out to be low or high.


Most people turn out to have low levels and this goes a long way to explaining why they can’t shift an immunity problem like allergies, chronic skin conditions or infections. I often find people who cannot get rid of candida have low SIgA, for example, and that has to be sorted before anything else, otherwise the body just doesn’t have the ability to fight. Coeliacs and people with autistic spectrum disorders are renowned for having low levels, as do most Crohn’s and ulcerative colitis sufferers. Chronic stress has a major effect on SIgA levels too.

Low levels can also be a sign of an ongoing ‘immune-drainer’, if you like, in that an unsuspected allergy reaction or other immune problem is dragging the body down. This needs to be looked at carefully and may involve hunting for an auto-immune disorder or something that has been missed somewhere.

In my experience, if low levels continue, this then starts to drain adrenal function as the body struggles to cope and the person becomes more and more tired over time. This is why often an adrenal test is done with an SIgA test alongside as the two do tend to go hand in hand.


Occasionally, we find high levels of SIgA and this points more to an inflamed gut or to an acute immune response to some sort of ongoing infection. You can then check this with a gut inflammation test called PNM Elastase, which can also be done via a stool test. In fact, quite often the best route for testing is to do one stool test and check SIgA, leaky gut and PNM Elastase at the same time. At the time of writing, this costs around £100 and can be arranged through a nutritionist or online.


The good news is that lowering stress, making lifestyle changes and supporting your nutrition can all have a positive effect on your SIgA levels.

Of course, eating a good diet is the place to start. Balancing blood sugar by avoiding refined carbs and eating every 3-4 hours seems to be crucial, not least for your adrenal health and inner body stress. If you like, you can download a free copy of the Purehealth Wellbeing Diet using the link below, which will give you an idea of what I consider a healthy, healing diet should be.

Next, take steps to lower your stress by using relaxation techniques like meditation and getting some exercise.

Increasing SIgA

Nutritionally-speaking, there are a few approaches to increase levels, but the best I have found to date involves using probiotics, beta glucans and digestive enzymes with targeted vitamins, minerals, fatty acids and amino acids. Nutrient-wise, we know that choline, essential fatty acids, glutathione, glycine, glutamine, phosphatidylcholine, Vitamin C and Zinc are all required in some way or another for efficient production of SIgA so it makes sense at least to optimise those.

It generally takes a good 4-6 months to make a difference, but consistency is the key. In some cases where SIgA levels are very low and don’t want to come up easily, it can take years and then all you can do is support the immune system as much as possible whilst you hunt down the hidden ‘drainers’ we mentioned before.

I tend to think of these tough cases as having layers of issues that are pulling the immune system down. For example, often I have to correct a candida, bacterial or parasitic infection (or all three, yikes!), boost adrenal and thyroid output, augment cellular and liver detoxification, detoxify heavy metals, kill latent viruses, eliminate allergens as much as I can, re-heal a leaky gut, improve absorption and re-nourish a run-down person with vitamins, minerals and amino acids. That’s a big job, but sometimes those layers have to be knocked off one by one to remove all the pressures from the immune system. Thankfully, most low SIgA levels come up a lot easier than that!

Lowering SIgA

If SIgA turns out to be high, we need to find any culprit causing inflammation or infection and deal with that, and then generally lower inflammation in the body.

Immune modulators like probiotics and aloe vera can help, as can enzymes between meals and lots of omega 3 fatty acids like EPA and DHA. If the body is too acidic, it needs to be corrected with alkalising minerals like potassium and, conversely, we also need to ensure there is enough acid in the stomach.

To offset any inflammatory damage to tissues, antioxidants and minerals including Zinc and Selenium are needed to combat free radical attack.

Phew. Sounds complex and sometimes it is. However, it IS easy to find if you have an SIgA problem and if you suffer from chronic immunity issues like allergy and intolerance, it could be a very big key to achieving improvement. SIgA tests are cheap as chips compared to the knowledge they give you – about £40-£50 usually – so get yours organised and may all your levels balance quickly! Good luck.


Most tests have to be organised by a nutritionist. The labs listed conduct the tests and will help you find a local practitioner or you can find a local nutritionist at

Labs who conduct SIgA testing: BTS (stool):, 0844 330 1909, Genova Diagnostics (saliva):, 020 8336 7750, Doctors Data Inc (stool):, 08712 180052.

The Doctors Laboratory does blood testing of normal IgA:, 020 7307 7373.

If you wish to talk it through with me or arrange a test, contact me on 01926 419220,, or if you wish to order online, you can do so at

You can also get a free copy of the Purehealth Wellbeing Diet from my site at or by contacting me.

First published in 2011

Textbook of Natural Medicine, 3rd edition, Volume 2, Pizzorno & Murray, published by Churchill Livingstone.
Biological Testing Services Practitioner Guides
Genova Diagnostics Practitioner Guides

If this article was of interest you will find many other articles on unlikely allergies and allergy connections here – and links to many relevant research studies here.

For more on the more 'mainstream' allergies check in to our 'allergy and intolerance home page' – and for ideas on alternative foods go here.

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