There are new recommendations in the BMJ outlining that subclinical hypothyroidism should not be treated with synthetic T4 (Synthroid)… AGREED! When thyroid levels are just mildly shifted from normal it’s likely that there is a systemic hormonal imbalance, and not necessarily an inherent problem with the thyroid gland itself.

Conventionally, when assessing thyroid function doctors measure Thyroid Stimulating Hormone (TSH) in the blood. This is a hormone released from the pituitary gland in the brain, which in turn stimulates the thyroid gland to make T4. The T4 then circulates back to the brain and depending on its levels, the brain will either continue to secrete the same amount of TSH to keep T4 levels steady, or if T4 is low it will increase TSH to increase T4 output, or conversely decrease TSH to decrease T4 secretion. Meaning that high TSH indicates low thyroid function, and low TSH indicates overactive thyroid function.

Supplementing with synthetic T4 may help to lower TSH, but very commonly it won’t help the patient to feel any better. In my practice the more common issue is poor conversion from T4 to the more active form of thyroid hormone T3. There are many factors that help or hinder this conversion, but the 2 most pervasive issues in my patient population are:

  1. Stress
  2. Low progesterone

Balancing this hormonal imbalance can sometimes be very simple, and other times be very extremely complex. This is where individualized medicine really matters. We cannot look at the thyroid in isolation, and will often investigate female hormones, cortisol and nutritional deficiencies as well. If you’re looking for answers and need more extensive testing and whole picture investigation come see me, I can help.