Testosterone is a hormone essential to the health and wellbeing of both sexes although in much higher levels in men. Low levels are often associated with low libido, muscle and strength loss, fat gain, erectile dysfunction and memory and energy issues. Low levels may indicate pituitary issues, Klinefelter, Kallman and Prader-Willi syndrome or testicular malfunction. Various diseases, testicular injury and medications can also cause low levels. Increased high levels may indicate tumors, hyperthyroidism and ovarian and adrenal issues in women.
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