As a naturopath and naturopathic practitioner, Dr. Jenkins regularly checks for high estrogen levels in his patients with thyroid problems. Excess estrogens increases the levels of TBG (thyroid binding globulin) which is where a protein binds to to the thyroid hormones T4 and T3  and causes them to be inactive. In order for the T4 and T3 to become active, the protein needs to be cleaved from them in order to produce Free T4 and Free T3 which are biologically active. When a person’s estrogen is dominant, it causes the liver to produce high levels of TBG. High levels of TBG decreases the levels of Free T4 and Free T3, leading to hypothyroidism. Dr. Jenkins recommends that his patients perform a Salivary Hormone Test to determine the estrogen levels. The test can be done in the convenience and privacy of your own home by collecting one vial of saliva.