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Thyroid Testing – Is TSH Enough?

Time to get a little controversial. Is TSH enough? It depends. For some, it's not and it certainly doesn’t give a complete, functional view of thyroid health.

First, quick overview of low thyroid symptoms:

-Weight gain

-Fatigue

-Low Mood

-Dry Skin

-Bloating/Digestive Issues

-Constipation

-Heavy Menstruation

-Brain Fog

-Low Blood Pressure

-Muscle Aches

-Low Libido

Note - these symptoms are non-specific. Many can be explained by other medical conditions or lifestyle factors. Having a few doesn’t necessarily mean you have thyroid dysfunction, but the more symptoms, the increased likelihood of its involvement. It shows how thyroid affects so many functions in the body besides controlling our metabolic rate!

Thyroid – Gland at base of neck that secretes two thyroid hormones, in different amounts: T3 (20%) and T4 (80%)

Understanding the Full Thyroid Panel:

TSH – Released by pituitary in brain and tells thyroid gland to make T3 and T4. It’s an indirect measure of thyroid health since hormone production decreases the amount of TSH produced.

Free T4 – The ‘inactive’ thyroid pro-hormone that gets converted to T3. T4 can also be converted into reverse T3 (see below.) Synthroid, the medication for hypothyroidism, is a bio-identical version of T4 hormone.

Free T3 – The ‘active’ thyroid hormone that is converted from T4. This hormone has up to 20-fold greater affinity for thyroid receptors compared to T4. The conversion takes place within cells, mainly in the liver (so requires proper liver function), our GI tract, muscles, and heart.

Reverse T3 (rT3)– T4 can either be converted into T3 or rT3. RT3 is inactive, it’s like a metabolic reserve that doesn’t increase metabolic rate of our cells. Our body is clever – it favours the conversion to rT3 in times of stress, low calorie diets (thinks it’s starving), inflammation, nutrient deficiency, etc. with hopes of conserving energy and lowering metabolic rate during perceived 'hard' times.

TPO or TG – antibodies that target thyroid tissue, eventually impacting hormone production.