How Someone Ends Up Without a Thyroid
There are several ways that someone can end up without a thyroid gland. First, you can be born without a gland, or with a malformed or non-functional gland. This is called "congenital hypothyroidism." When it's found, newborns are started on thyroid hormone replacement, to avoid the signs and symptoms of this condition, which can include failure to grow, lethargy, developmental delays, and even mental impairment. Typically, in the United states, mandatory "heel stick" blood tests conducted at birth measure for thyroid hormone, in order to detect this condition, and allow treatment to begin right away. More information on congenital hypothyroidism:
Second, you don't have a thyroid if your gland has been surgically removed. In the United States, surgery to remove the thyroid gland, called a thyroidectomy, is most commonly performed on many patients who have been diagnosed with thyroid cancer, or who have had inconclusive thyroid nodule biopsies that couldn't rule out thyroid cancer. In some cases, surgery is also performed as a treatment for an enlarged thyroid, known as a goiter, or multiple nodules. Surgery is also done in some cases of Graves' disease/hyperthyroidism, and less commonly, for uncontrollable cases of Hashimoto's disease.
No Thyroid Gland Means You are Hypothyroid
Whether you don't have a thyroid gland because you were born that way, or have had your thyroid surgically removed, the end result is that you are hypothyroid. Hypothyroidism is a term that refers to a condition where you have insufficient thyroid hormone. You can be hypothyroid and still have a thyroid gland — your gland, however, is not producing enough of the essential thyroid hormone, which delivers oxygen and energy to the cells, tissues, and organs of the body. In addition to congenital hypothyroidism or surgical removal of the thyroid, you can become hypothyroid for a number of other reasons:
- Iodine deficiency
- Autoimmune Hashimoto's disease
- Radioactive iodine treatment (radioiodine ablation) for Graves' disease/hyperthyroidism
- Use of certain medication - i.e., lithium — that slow the thyroid
Hypothyroid and Thyroidless vs Hypothyroid with a Thyroid: What's the Difference?
Whether a patient has a thyroid or not, hypothyroidism requires thyroid hormone replacement treatment. Hypothyroid patients require some form of prescription drug treatment, whether a synthetic T4 only treatment (levothyroxine, Synthroid, Tirosint), a T3 treatment (liothyronine/Cytomel), a combination of synthetic T4 and T3, a natural desiccated thyroid drug (Nature-throid, WP Thyroid, Erfa, or generic natural thyroid), a specially-compounded prescription medication, or some combination of the above medications. What are the key differences for patients who are hypothyroid due to lack of a gland, versus those who still have a thyroid gland, but whose gland is not producing any or enough hormone?
- While people who still have a thyroid gland are counseled to minimize consumption of goitrogenic foods (thyroid-slowing foods, especially raw cruciferous vegetables), those who do not have a thyroid gland do not need to be concerned about these foods. (Note: warnings about soy still apply, however, as soy can interfere with the body's ability to absorb thyroid hormone.)
- People without a thyroid gland may find it easier and faster to get stabilized on a dose of thyroid medication, and may have less dosage fluctuation month-to-month and year-to-year, versus those with a gland. When a gland is still present, it may still be providing some thyroid hormone, but the thyroid's hormone production may fluctuate, shifting a patient from mild hyperthyroidism to mild hypothyroidism, and causing fluctuating blood test levels and changes to more frequent changes to medication dosage.
- People without a thyroid gland may find that they need the addition of the T3 hormone in some form. A functional thyroid gland produces both T4 — the inactive thyroid hormone, and some T3. The T4 that is produced is converted into T3, the active hormone. The conversion takes place primarily in the thyroid gland. When you don't have a thyroid gland, you are not producing any thyroid hormone, and the T4 to T3 conversion process has to take place in peripheral tissues. Since you have no T3 being produced by your thyroid, if you are taking a T4-only drug like levothyroxine, if your T4 to T3 conversion is not optimal, you may find yourself low in active thyroid hormone, which can cause hypothyroidism symptoms unless a T3 drug (like liothyronine, or natural desiccated thyroid) is added to your treatment.