Many of the patients I see have at least one autoimmune condition. And unfortunately, for the most part it’s one of those situations of when it rains it pours: people who tend to have autoimmune conditions tend to have more than one. Many of these autoimmune conditions have one surprising thing in common: people tend to get better when they avoid wheat. Thankfully, we’ve all seen the myriad of gluten-free products available to us in the grocery stores. But how exactly does wheat exacerbate an autoimmune condition, like Hashimoto’s Thyroiditis?
Wheat is a grain that is primarily a starch but it also has many proteins within its structure – glutenins, gliadins, agglutinins, prodynorphins. All of these proteins have parts that can activate the immune system. But in the case of thyroid autoimmunity, it’s actually the glutamate decarboxylase (GAD) in the wheat, not the gluten, and an enzyme made by our own bodies to break down the wheat, called tissue Transglutaminase (tTG) and that end up being the culprits. The tTG enzyme has many roles in the body but it also important in the breakdown of gliadin. The GAD, on the other hand, plays a role in ripening the wheat. These are the proteins that are the thyroid cell lookalikes.
So you can surmise from the above that every time you eat wheat, you are exposing your immune system to that magical epitope that looks like a virus, that looks like your thyroid gland, which looks like many other tissues (hence the co-occurrence of various autoimmune diseases). Autoimmune diseases that tend to occur together with Hashimoto’s are celiac disease, vitiligo, multiple sclerosis, diabetes Type I, rheumatoid arthritis, and chronic urticaria. In short, the immune system gets activated and starts attacking everything that looks like wheat.
Dr. Hakuru Hashimoto took a look at some diseased thyroid tissue from someone who was hypothyroid and noticed that it had been infiltrated by immune cells called B and T lymphocytes.
The lymphocytes are normally supposed to fight invaders, like viruses. Instead, they were attacking the body’s own tissues. That’s not supposed to happen.
Pretty quickly after this, scientists came up with the idea that some viral or bacterial infections, like Yersinia, Cytomegalovirus, or Borrelia, may have caused the immune system to attack the thyroid gland[iii]. They just didn’t know exactly how a virus could get the body to attack itself. Among other mechanisms, they found that a viral infection of the thyroid itself could cause it to put up proteins like little flags called HLA II that calls the immune cells to it. However, for our wheat connection, I’d like to focus on another very interesting mechanism called molecular mimicry.
The idea is that the immune system identifies a virus by looking at just a little piece of it called an epitope. It’s akin to identifying a person only by looking at the shape of their nose. In our thyroid cells, especially on the enzyme, Thyroid Peroxidase (TPO), there are protein bits that look just like an epitope on the virus! So, the immune system is not that discerning – it just looks for the epitopes. Well, guess what other substance has an epitope lookalike? Yep, wheat.
Now, wheat does not actually start off the problem. In order to start the Hashimoto’s rollercoaster, you need to be genetically predisposed to it, and you need to have been exposed to things like ingesting foods high in iodine, pregnancy, hormonal imbalances, stress, toxins, heavy metals, smoking, botox injections, cytokine therapy, etc. Yet, after the initial trigger activates the immune response, something causes the immune system to perpetuate the attack over the course of the person’s life. In part, it is wheat ingestion that will perpetuate the autoimmune attack on the thyroid gland.
Not only does wheat have an epitope that is structurally similar to a part of our thyroid cells, wheat has a peculiar relationship with our intestines.
Normally, if healthy, the cells of our intestines are joined together by tight junctions. The space between the intestinal cells is so small that any particle larger than 15 angstroms, or 1 ten-millionth of a millimeter should not be able to pass between the cells. However, under certain circumstances, this space between the cells can become larger. We call this intestinal hyperpermeability, or, more lovingly “leaky gut.” If the intestine becomes leaky, larger proteins that would normally not gain access to the bloodstream are able to pass in between the intestinal cells. Once a foreign substance gains access to the bloodstream, it will come into contact with our lymphatic system, where our immune cells live, and you have the makings of a perfect immune storm.
So how does the intestine become leaky? Well, there are many ways including stress and bacterial infections, but you can guess at this point that the really crazy way our intestines become leaky is by eating wheat.
The way wheat (or actually the gliadin in the wheat) causes leaky gut is by triggering our intestinal cells to produce a protein called Zonulin (also known as Haptoglobin 2 precursor). Zonulin has the ability to ‘unzip’ the seams that normally join the intestinal cells together. When this happens, the intestine becomes leaky.
Like everything in the body that seems harmful, Zonulin serves a good purpose. If we have a penchant for, say, Eggs Benedict, and get exposed to bacteria, such as Salmonella, our intestines react to the bacteria by making more zonulin. This allows water to enter our intestines in large quantities and subsequently leave our intestines in the form of diarrhea. Our leaky guts can help our bodies to flush out toxins. Then, when the immune system is done fighting the Salmonella, the body produces less zonulin and the intestinal barrier is restored.
However, if we keep eating wheat, as many of us do, we keep our guts leaky and allow many substances to enter our bloodstreams and trigger immune reactions. If those substances have epitopes that look like parts of our cells, well, there you have the basis of wheat-dependent autoimmune attacks.
How likely is this to be a partial cause of your thyroid issues? Well, Hashimoto’s Thyroiditis is the most common cause of hypothyroidism in the US, affecting about 1-2% of the population, so, it’s pretty possible. In fact, some statistics list Hashimoto’s as being far more prevalent. In a recent study published in the Thyroid Research journal, test subjects had their thyroids biopsied to screen for thyroid cancer. Although it wasn’t the goal of the study, researchers were shocked to find that >5% of the subjects showed evidence of an autoimmune attack on the thyroid, even in patients with no symptoms of hypothyroidism. I know 5% doesn’t sound like a big number. But, when you consider that there are about 316 million people in the US, it means that 15 million might have their immune systems attacking their thyroid glands as we speak. All of this goes to say that it’s really, really common in both adults and children, whether you have symptoms or not. Unfortunately, women* are 15-20 times as likely to have this as men*.
So, of course, that leaves you wondering, how can one stop the immune system from attacking the body? Well, one relatively simple piece of advice is to avoid wheat. That’s easier said than done, of course, as wheat can be found in almost everything we eat. It can be hidden in things like sauces, meat fillers, yogurts, alternative kinds of milk like rice, soy, etc. It can be dusted on nuts to separate them. It can be in anything that has “natural flavors” or msg. It can even be on stamps and in beauty products. The list is daunting. What’s worse, even gluten-free products are not necessarily wheat-free. They figured out how to remove the gluten from wheat but keep in all the other proteins with immune triggering epitopes.
While the challenge to avoid wheat can be harrying, the good news is that avoiding wheat can have very healing effects on a variety of conditions. It can help restore the health of the intestine, providing a barrier that will not only keep wheat out of our bloodstream but also other substances that can cause immune reactions. Autoimmune flares can be minimized. And, if the autoimmune attack can be stopped, while it’s not common, it is possible for some people to even regenerate their thyroid tissue and return to normal thyroid function!
When you weigh the possible effects of Hashimoto’s on your life, such as heart failure, muscle failure, bone loss, infertility, miscarriage, menstrual abnormalities, and brain inflammation, to name a few, then add to that the symptoms of the 50+ autoimmune disorders that can be connected to wheat, I think it’s worth really trying to avoid it. At least give it a try and see how you feel!
* Language used in the study referenced.