Thyroid is the endocrine system is an important organ,there is a clear distinction between Thyroid and other body system (such as respiratory, etc), but it contact closely with the nervous system, interact with each other, known as the two major biological information systems, without their closely cooperation, the body's internal environment can not be maintained relatively stable. Endocrine system, including many of the glands, after the endocrine glands are stimulated appropriately by nerve , can make some of these endocrine cells release chemicals efficiently, the chemical was sent to the corresponding organ by the blood circulation to play regulating function, this highly efficient chemical are called as hormone.thyroid is the largest endocrine glands in Human endocrine system, it can secret thyroid hormone secretion after stimulated by nerve, and those hormone will pay a physiological effect after being sent to the corresponding organ in the human body.

If you want to know more about it,you may have one quantum resonance magnetic analyzer,the detailed reference standard is below,pls have a look at that.Thanks!

Reference Standard:- Normal    + Mildly Abnormal    ++ Moderately Abnormal    +++ Severely Abnormal

Thyroid secretion index:2.954-5.543(-) 1.864-2.954(+) 0.514-1.864(++) <0.514(+++)