Now that we’ve covered the basics of how your thyroid works (read more here) let’s look at the difference between hypothyroidism and autoimmune thyroid disease. You can be hypothyroid and not have autoimmunity. You can be autoimmune and not have hypothyroidism (in the earlier stages of your disease process). Or you can have both.
Hypothyroidism means a low functioning thyroid, regardless of the cause. It simply means your thyroid is not putting out enough thyroid hormone to keep your body functioning as well as it should.
The cause of hypothyroidism could be a physical defect with the thyroid gland, a signaling problem from the pituitary gland to the thyroid to produce more hormone (HPA axis), or not having enough raw materials to make enough thyroid hormone (iodine or other nutrient deficiency) to start with. Remember it’s estimated that only 10% of people diagnosed have hypothyroidism alone (without autoimmunity).
Autoimmune thyroid disease does not originate in the thyroid because it isn’t caused by a dysfunctional thyroid gland. It’s a malfunctioning immune system that is attacking your thyroid by mistake.
Autoimmunity is where your immune system mistakenly identifies a substance (that’s composition is similar to a tissue in your body) as foreign and it launches an attack on that substance and the tissue.
For instance, gluten has a protein that is similar to a protein in your thyroid gland so when you eat gluten your immune system goes to work attacking the gluten and the gland. This is called molecular mimicry.
What causes the hyperactive immune system in the first place? There are a few different theories on this and ultimately the cause depends on the individual. 3 factors need to be present for autoimmunity to exist: a genetic predisposition (you have a gene that runs in your family), exposure to a trigger (like an infection) and intestinal permeability (leaky gut). The genetic part is pretty self-explanatory, someone in your family has autoimmunity and you inherit that gene. Basically you have a weak link in your DNA.
Once you have a gene you need a trigger. Triggers are anything that causes an immune response and the trigger can be different for everyone. I want to keep this simple so I’m not going to go into the specifics of which substances activate different antibodies I will just break this down into common triggers.
Dietary substances like gluten or dairy, infections like strep or a virus, toxins like pesticides or radioactive substances and stress which lower immunity are all triggers.
Finally we need intestinal permeability to have autoimmunity. On a microscopic level our intestines are made up of tight junctures that are meant to keep the waste in place and moving along to exit our bodies. But when the intestine becomes permeable the junctures loosen and some of those bad substances enter our blood stream and float around.
When our immune system identifies these foreign substance it goes on the attack and creates antibodies to help it recognize the invader more quickly next time it comes in contact with it. The problem is some of these substances have a similar make up to our own tissue so when the immune system attacks the substance it also attacks our tissue. It’s a case of mistaken identity.
When you go to your family physician and are diagnosed with hypothyroidism she will treat the under functioning thyroid with replacement hormone.
But if she doesn’t test for antibodies she doesn’t know if you really have a thyroid problem or an immune system dysfunction. And while you may still need replacement hormone for autoimmunity there is a lot more going on than meets the eye.
To truly get better you need to calm the inflammatory response from your immune system, heal the leaky gut and make lifestyle changes that promote healing. This is the one thing I want to educate everyone on because to me it is SO obvious that hypothyroidism and autoimmunity are not the same (thyroid) problem.
You have to insist that your doctor digs deep enough to find out what is really going on in your particular case and be your own advocate.
