Typically physicians will ask for an assessment of T4, T3 and TSH when they think the thyroid may be involved in some issue. Unfortunately, they do not take into consideration that about 80% of the T4 – T3 conversion typically happens in the liver. Nor do they take into consideration that either hypo or hyper adrenal function can interfere with the enzymes that do the conversion
To expect them to consider things that can interfere with TSH readings from the list below, would be expecting just too much:
- Stress: Did you know that cortisol suppresses the release of TSH from the pituitary. (Corticosteroid steroid medication like prednisone does the same thing.)
- Inflammation: Cytokines (inflammation communicators) suppress both TSH (released from the pituitary) and thyroid hormones T4 and T3. This can be caused by acute and chronic illness, infection, smoking, and other problems discussed below. (Also called euthyroid sick syndrome or low T3 syndrome.)
- Glutathione: Decreased levels of glutathione can lead to Hashimoto’s thyroiditis
- Autoimmune thyroid disease: It is another source of inflammation that suppresses TSH. (Even when the tissue is essentially hypothyroid.)
- Insulin and Leptin resistance: Insulin and leptinupregulate D2 deiodinase and T3 at the pituitary – but decrease T3 everywhere else.
- Standard thyroid medication (T4): Much of T4 converts to reverse T3, which remains wholly undetected by the pituitary. This is why using TSH to monitor T4 therapy is so pointless.
- Low calorie dieting: It can take years to up-regulate cellular deiodinase D1 after suppression by dieting. This is why dieters suffer metabolic shutdown.
- Environmental toxins.
- Pill and HRT drugs: Both can interfere with the readings.
- Increasing age: TSH, T4 and T3 all decline with age. (Reverse or rT3 increases with age.)
- Pituitary dysfunction (rare) Iron deficiency.
- Protein deficiency.
If TSH is in question, you may want to consider the following:
1) First you may want to recognize that the American National Academy of Clinical Biochemistry narrowed the reference range for TSH from 0.5 – 5.0 to 0.2-2.5 mIU/L
2) That TSH tests can change depending on: the time of day; whether you ate before the test; etc
3) Then you may want to look at:
additional tests for the thyroid:
- thyroid anti-bodies
- free T3
- free T4
or with the adrenals:
- salivary cortisol
or some other tests:
- serum Vitamin D
- gliadinIgG (a gluten test)
- urinary iodine ( you can use the iodine blot on your arm – but not very accurate)
- oestrogen dominance
Some of the causes of thyroid related imbalances:
- Adrenal insufficiency: A deficiency in the adrenal hormones like DHEA or cortisol is a common underlying issue in thyroid disorders. If it is not corrected, patients may find that they cannot tolerate thyroid replacement treatment. Cortisol deficiency may suppress TSH.
- Oestrogen dominance: Caused by stress and pollution. Oestrogen suppresses thyroid function.
- Selenium deficiency: Selenium is necessary for the conversion of T4 to T3. (Incomplete conversion results in high levels of reverse T3 (rT3), an inactive hormone.) Selenium has also been shown to reduce autoimmunity against the thyroid (ie. to treat the underlying cause of Hashimoto’s thyroid disease.) It also protects against the toxic effect of iodine on the thyroid.
- Iodine deficiency: A urine analysis can check your iodine levels. If necessary, use a proper low-dose iodine supplement, not kelp. Kelp is not effective because it also contains bromine which inhibits thyroid function. Hashimoto’s patients should use iodine with caution, as large doses may aggravate your condition. If an iodine deficiency has been established with a urine test, then a small dose of iodine can be used, even by Hashimoto’s patients. Iodine is not the solution for every thyroid problem, but a deficiency should be corrected. Iodine is not just about thyroid. It is important for the health of brain, breasts and uterus. And if an iodine deficiency is not corrected, then the body will harvest iodine from the thyroid hormone medication.
- Iron deficiency: Iron is required to make the thyroid hormones.
- Environmental toxins: Many toxins can affect the thyroid gland: mercury, bromine, chlorine, fluoride, PCBs and others. According to new research presented at the American Thyroid Association meeting, “environmental factors account for about 30% of the risk for autoimmune thyroid disease”. Of concern are certain pharmaceutical medications, cigarette smoking, stress, selenium deficiency, pesticides, polychlorinated biphenyls (PCBs), and bisphenol A (BPA).
- Autoimmune disorder: Thyroiditis or hashimoto’s is a common reason for an underactive thyroid. This can also be the result of low glutathione (which is also the master anti-oxidant and the master chelator) levels – which are required for both development of the immune cells AND to keep the proper ratios of the immune cells. In some cases, ie. T1 & T2 if either become dominant; we can have a huge number of disorders occur. Immune disorders can also result from low levels of Vitamin D.
Be responsible, do your research, find a good health practitioner. Here’s to your health!