Total T4

T4 is the primary hormone released from the thyroid gland. T4 is largely inactive metabolically, and needs to be converted in other tissues to the active thyroid hormone, T3. T4 is often carried in the bloodstream via binding proteins. The Total T4 metric is a measurement of the protein bound T4. High levels can indicate excessive supplementation, hyperthyroidism, or a poor conversion of T4 into T3. Low levels are suggestive of primary hypothyroidism. 

The thyroid hormones govern metabolism, or the body’s energy production. Poor thyroid function be caused by and can contribute to stress. Stress inhibits thyroid hormone production and utilization, and the stress systems tend to take over to compensate for low thyroid function. Thyroid function is vital for maintaining gut health, too. Thyroid hormones govern the growth and proliferation of the cells in the gut, and promote gut motility, support the immune system, and enhance digestive enzyme and stomach acid secretion. Low thyroid function is common in aging and several chronic and age related diseases, as energy metabolism is what fundamentally maintains the structure and function of every cell, tissue and organ system in the body.