Low thyroid (also called hypothyroidism) is a condition in which the thyroid gland does not make enough thyroid hormone. Think of it as an underactive or sluggish thyroid.
How common is it?
Hypothyroidism affects 30 million women and 15 million men. I have seen more hypothyroidism here in Fresno than I ever saw in Washington. Why might that be? One theory postulated by naturopathic doctors who specialize in environmental medicine is that pesticides used in agriculture can damage the thyroid gland.
What are symptoms of low thyroid?
- Low mood (low grade depression)
- Cold intolerance, feeling cold, or having a body temperature less than 97.6◦F.
- Thinning hair
- Poor concentration and memory (some patients describe this as “brain fog”)
- Hoarse voice
- High cholesterol
How to get tested for low thyroid?
Visit your doctor and review your symptoms. You will need a physical exam and blood work. A comprehensive, thorough blood test panel includes:
- TSH or Thyroid Stimulating Hormone: Often times, doctors will only order a TSH test. TSH is not a thyroid hormone; it is an anterior pituitary hormone. A low TSH means the brain is satisfied with the amount of circulation thyroid hormones. A high TSH means the brain is “screaming for more.” Many conventional doctors believe that only when a TSH is greater than 5, is it high enough to warrant treatment. However most naturopathic doctors (and reproductive endocrinologist) believe that an optimal TSH is less than 2.5.
- Free T3 and free T4 are the actual thyroid hormones that are circulating in your body.
- Reverse T3
- Anti-TPO and anti-TG antibodies
- Because naturopathic doctors look at the whole picture and not just the gland in your neck, your doctor may also order vitamin D, ferritin (iron), celiac panel, or other tests depending on his/her initial evaluation.
If you are trying to get pregnant, have infertility or a history of miscarriages, comprehensive thyroid testing is imperative. Studies have shown women who have positive thyroid antibodies have a higher chance of miscarriage, even if their thyroid levels are normal. Furthermore, low dose thyroid hormone can reduce their chance of miscarriage.
Once you have a blood test requisition, make sure you do your test properly to get the most accurate blood test values!
- Do not take any high dose Biotin supplements or over-the-counter thyroid supplements for 2 weeks before your blood test.
- Biotin does not impact your actual circulating thyroid levels – it alters the chemicals used in the blood test assay and can make your numbers look better (or worse) than they really are. Both Quest and BioReference Labs use an immunoassay to measure thyroid levels that is impaired by circulating blood levels of biotin!
- When you initiate thyroid treatment or change your dose, you need to repeat your blood test in 4-6 weeks.
- If your doctor prescribed a natural, dessicated thyroid hormone like Armour or Nature-throid, it is important that you don’t take your thyroid hormone for 24 hours before your blood test.
- If you have hypothyroidism and get pregnant, it is important that you repeat your thyroid testing every trimester and also 4-6 weeks post-partum.
Take home message:
- Take an inventory of your symptoms
- Schedule a visit with a naturopathic doctor
- Stop taking Biotin and thyroid supplements for 2 weeks
- Get a comprehensive blood test; for follow up testing, do not take T3 containing thyroid hormone (Armour, Nature-throid, Cytomel, liothyronine, WP-throid, compounded dessicated thyroid hormone) for 24 hours before a blood draw.