Can Milk Contain Gluten?

[T.H.]

You really can't compare cow milk and human milk at all. We have two VERY different digestive systems.

But do we have two very different mammary systems, at least in how they function and what substances can make it through into the milk? (not being snarky...I'm actually kind of curious about this now. )

[tarnalberry]

But do we have two very different mammary systems, at least in how they function and what substances can make it through into the milk? (not being snarky...I'm actually kind of curious about this now. )

I don't know about the mammary system, but nothing can get into the body to get into the mammary system without going through the digestive tract first.

[Skylark]

But do we have two very different mammary systems, at least in how they function and what substances can make it through into the milk? (not being snarky...I'm actually kind of curious about this now. )

It IS interesting! Like Tarnalberry says, food has to get absorbed through the digestive system before it makes it to the milk. Cows have four stomachs, one full of bacteria, fungi, and protozoa and special digestive enzymes that break down fiber and other plant matter that is indigestible to humans. They also chew a cud, as you probably know, which helps them break down fiber better. They can even digest cellulose, the fiber in wood. That's how they can live on grass and hay that would leave us sick and starved. Their small intestine is different from ours, and they absorb more fatty acids and less glucose from food. The glucose mostly feeds the bacteria. This is kind of an interesting read. Open Original Shared Link Wikipedia has a more technical article. Open Original Shared Link

It is entirely possible cows and other ruminants could be fully digesting gluten since their digestive enzymes are different, food is digested longer and much more thoroughly, and they have so many gut microbes helping them out.

[T.H.]

- I love the fact that you always have such interesting information!

I swear, I have learned more from your links...

In that vein...I don't suppose you've ever found a good source on the limitations of the gluten tests?

The information I've heard (can't even remember where anymore!) is that some of the gluten tests have more trouble detecting gluten if it's been fermented, because the test has more accuracy detecting 'pieces' of gluten that have not been broken down to that extent, even though these pieces are still large enough to cause us trouble - soy sauce was mentioned, as I recall. I have never looked into it too much myself to see the specifics of this information, don't even know if it applies to all tests, or just some (I believe the ELISA test is the one I heard it mentioned re:). So if you had any information you've ever found on it, I'd love to hear.

I recall barley testing is still something that needs a bit of tweaking before it's perfected (Open Original Shared Link ), so it doesn't seem like it would be outside the realm of possibility for it to have some trouble too.

The reason I'm curious in this instance with cow's milk is that with your information it seems like maybe there could be issues: with the ruminant breaking down gluten further than humans do...does that make it harder for our tests to detect it? Or at the very least make them less accurate? Or is it not even an issue? (I feel the researching bug take hold now)

If it weren't so gross to think about, I'd love to get the actual contents of a grain fed cow's stomach tested just before the contents leave the stomach, and then have those same contents tested on a willing celiac to see if they react...which, yeah, okay, so obviously I'd make a better evil scientist than a good one, if I'm thinking of subjecting someone to that, LOL.

[dilettantesteph]

I don't think you are alone either. My own sensitivity comes and goes but I'm not to where I react to 1 ppm. I try to eat whole foods I prepare myself for the most part because of those studies on refractory celiac. Besides, it's healthier anyway. I'm really starting to appreciate how bad processed foods are for us.

Awareness has gotten so much better. When I first came here trying to figure out what was wrong, I kept being told that I couldn't possibly be reacting to gluten in gluten free foods. It was pretty frustrating.

I agree with you that if cows are eating 100% wheat, there should be detectable gluten in there even in the 1-3 ppm range, if gluten can get into the milk that way. That leads me to question something. I don't have access to the full paper. Maybe you can tell me. This worried me a little:

"no gluten proteins or gluten fragments could be detected above background in any of the bovine milk samples, whereas gluten was easily detected in spiked samples"

I used to work in an analytical company looking for trace contaminants. We were told that if we couldn't detect the target compound above the background that it wasn't there. I changed the procedure in one case so that the background could be separated better from the target compound and found that many of the samples which had been found to be negative for the target compound were actually positive. I wonder a bit about that in this paper. I wonder what the apparent concentration was in the spiked samples, and whether they contained the same amount of background noise. Is there anything in the paper which would answer my questions?

[Skylark]

They spiked to 1 ug/mL. I'm sleepy, but isn't that about 1 ppm?

For this purpose, two late-lactation Holstein cows (Bos taurus) were initially fed a corn-containing diet. The corn portion of the diet was slowly changed to wheat, from 0% to 25%, 50%, 75%, 82.5%, and 100% wheat. Each experimental diet was fed ad libitum for 3 d before milk sample collection. The milk was divided into two identical sets of aliquots of 40 mL. One set of samples was analyzed for the presence of gluten and gluten-derived peptides by commercially available gluten detection kits based on the R5 monoclonal antibody [5]. The second set of milk samples was analyzed for the presence of gluten proteins and peptides known to contain T-cell–stimulatory epitopes of gluten involved in the induction of celiac disease-related symptoms [1], [6], [7] and [8].

No HMW glutenin-derived peptides could be detected in the various milk samples by the monoclonal antibody–based competition assay (gray bars). However, when spiked with 1 μg/mL of the HMW glutenin standard, all glutenin proteins could be fully recovered (black bars). Similar results were obtained with monoclonal antibodies specific for α- and γ-gliadin peptides (not shown).

Their graph shows good recovery in the spiked samples ranging from from 0.9-1.2 ug/ml, with error bars around 0.1 ug/ml on the assay with the largest error and to my eye maybe 0.02 on the better samples. There is some background in the assay in two of the un-spiked samples and it looks to be between 0 and 0.03 ug/mL on the graph, well within the error bars on the spiked samples if that helps. It looks to me like they could have easily seen 0.5, probably 0.1, but 0.02 would be in the noise.

Here are references 6, 7, and 8 that describe the T-cell stimulatory epitope methods.

[6] E.H. Spaenij-Dekking, E.M. Kooy-Winkelaar, W.F. Nieuwenhuizen, J.W. Drijfhout and F. Koning, A novel and sensitive method for the detection of T cell stimulatory epitopes of alpha/beta- and gamma-gliadin, Gut 53 (2004), pp. 1267–1273.

[7] L. Spaenij-Dekking, E.M. Kooy-Winkelaar, P.A. van Veelen, J.W. Drijfhout, H. Jonker and L. van Soest et al., Natural variation in toxicity of wheat: potential for selection of non-toxic varieties for coeliac disease patients, Gastroenterology 129 (2005), pp. 797–806.

[8] C. Mitea, R. Havenaar, J.W. Drijfhout, L. Edens, L. Dekking and F. Koning, Efficient degradation of gluten by a prolyl endoprotease in a gastrointestinal model: implications for celiac disease, Gut 57 (2008), pp. 25–32.

[dilettantesteph]

Thank you.