Nelson Vergel
Founder, ExcelMale.com
Thyroid Function:
The thyroid is a butterfly-shaped endocrine gland located in the lower front of the neck. It produces thyroxine or T4, which is converted to tririodothyronine, or T3. T4 production is controlled by thyroid stimulating hormone or TSH, a hormone produced by the pituitary. Hypothyroidism, or low thyroid hormone production, can cause sexual dysfunction as well as depression, fatigue, dry skin and hair, weight gain and increased sensitivity to the cold. Blood tests to measure TSH, T4 and T3 are readily available and widely used.
The American Thyroid Association (thyroid.org) has great comprehensive information on how to determine if you have hypothyrodism that could be causing your fatigue.
Testosterone may decrease levels of thyroxin-binding globulin, resulting in decreased total T4 serum levels and increased resin uptake of T3 and T4. Free thyroid hormone levels remain unchanged, however, and there is no clinical evidence of thyroid dysfunction.
Once thyroid hormone blood levels have been normalized, testosterone tends to increase naturally.