"Your thyroid is an important organ to your weight loss efforts"
It it or the hormones it produces are working well, you should be able to lose weight relatively easily. If it is not working well or the hormones it produces are not working well or in too little quantity, then you will have a barrier to weight loss and unexplained weight gain.
This gland is located on your neck. It is located below the adams apple for men and in the same location for women. It has a butterfly shape when you look at the body from the front.
T4 and T3
It does this through the hormones it produces. The two main hormones are thyroxine, (which I wrote about in the “Fat Burning Hormones” section) and triiodothyronine (pronounced try-iyodo-thy-roneen). They are also referred to as T4 and T3, respectively.
Thyroxine (T4) is produced in greater quatity to T3 but is the not main active hormone that is produced. It is converted to triiodothyronine (T3). T3 is the hormone that does most of the work associated with this gland. It however, is dependent on T4 to be produced.
What They Regulate
These two hormones regulate a number of physiologic processes, including growth, development, metabolism, and reproductive function1,2
Iodine is an essential component of producing hormones triiodothyronine (T3) and thyroxine (T4), and is therefore essential for normal function.
To meet the body's demand for T4 and T3, the gland traps iodine from the blood and incorporates it into its hormones that are stored and released into the circulation when needed.
In target tissues, T4, the most abundant circulating hormone, can be converted to T3 by selenium-containing enzymes known as deiodinases. Deiodinase (dee-iyo-din-ayse) is an enzyme in your body that are unusual because they contain selenium. Selenium is needed for the production of the thyroid hormones.
Regulation
The regulation of thyroid function is a complex process that involves the hypothalamus and pituitary gland. In response to thyrotropin-releasing hormone (TRH) secretion by the hypothalamus, the pituitary gland secretes thyroid-stimulating hormone (TSH), which stimulates iodine trapping, T3 and T4 synthesis, and release of T3 and T4 by the gland.
The presence of adequate circulating T4 decreases the sensitivity of the pituitary gland to TRH, limiting its secretion of TSH (diagram). When circulating T4 levels decrease, the pituitary increases its secretion of TSH, resulting in increased iodine trapping as well as increased production and release of both T3 and T4.
Iodine deficiency results in inadequate production of T4. In response to decreased blood levels of T4, the pituitary gland increases its output of TSH. Persistently elevated TSH levels may lead to hypertrophy (enlargement) of the this gland, also known as goiter.3
It also regulates body temperature carbohydrate beak down, mental clarity, energy levels, general well-being, vitamin absorption (all of which help weight loss), sex drive, skin moisture and nail strength.