Testosterone is the primary male androgen and plays a large role in regulating sexual function, the metabolism and bone and muscle strength and can even affect cognitive function. Testosterone is necessary in both men and women although in much higher levels in men.
Total testosterone represents all the testosterone the body produces. It does not reflect the levels of Free Testosterone in the body, which is the useable testosterone and a portion of the total amount. Measuring total testosterone can be a useful starting point in determining if an androgen deficiency exist. Lack of libido, erectile dysfunction, low energy, fat gain and muscle loss despite diet and exercise and other symptoms may indicate a possible androgen deficiency.
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