Let’s get something straight right out of the box. The human body is designed with a brilliance that none can truly understand. The interactions between the cells and organ systems are intricate beyond measure. Oh–except for the thyroid. That goes out in your 20’s.
What?
If your heart or liver or brain or kidneys were “giving out” in the 3rd decade of life alarms bells everywhere would be going off and you better darn well believe mainstream medicine is going to attempt to figure out why. But not so with the thryoid. Low levels on your bloodwork? Your doctor shakes his head, says these things happen and gives you your lifelong prescription for Synthroid.
So where’s the problem? The problem is that your thyroid is slowing down for a reason. Very often it has to do with toxic exposure. The thyroid has been called the “yellow canary” of the human body. It’s the organ that takes the initial beating when the body is exposed to allergies, heavy metals and environmental toxicants. Unless we try to identify the “why” of the thyroid failure, we’ve missed a valuable opportunity to identify and remove an exposure that the patient is experiencing that is harming their health. Sure–it may be “merely” the thyroid today, but in 20 years it’s very likely to be cancer, heart disease or dementia.
So what kinds of toxins or situations are known to affect the thyroid? This is by no means a comprehensive list, but here are a few:
- Perfluorooctanoic acid is Scotchguard
- Polybrominated diphenyl ethers in flame retardants in clothing and furniture
- Diabetes and thyroid problems are known to be linked
- Celiac disease / gluten allergy have been linked to thyroid disease
- BPA is well known to affect thyroid function as well
Now that we’ve gotten that out of the way, we need to go into a little thyroid physiology lessons. The thyroid produces two hormones, T3 and T4. T3 has a very short half life and gets broken down in the bloodstream relatively quickly. So the body, in its brilliance, makes primarily T4 in the thyroid and then the individual tissues that need T3 convert it when and where it is need.
The variable factor here is the conversion of T4 to T3. It is not always an efficient process. Things like stress, selenium deficiency can slow the conversion to T3, leaving you with symptoms of hypothyroidism but normal lab values. This is why supplementation with T3 (such as Cytomel or Armour) is trickier but will likely produce better outcomes. This particular article further supports this concept, demonstrating that those taking T3 achieved better body weight and better lipid levels.

