Testosterone and Cortisol Blood Test

Testosterone is a hormone that causes male characteristics. For men, it regulates the sex drive and controls bone mass, fat distribution, muscle mass, strength and the production of red blood cells and sperm. Heavy alcohol use, liver disease and using steroids can cause a decrease in testosterone levels. Women taking oestrogen therapy, however, may have increased testosterone levels.

Cortisol is a steroid hormone, produced by the adrenal gland. It's vital for survival as it's involved in various important functions such as immunity, regulating blood pressure and releasing insulin for blood sugar maintenance. Cortisol has been termed 'the stress hormone' because it's also secreted in higher levels during the body's 'fight or flight' response to stress, and is responsible for several stress-related changes in the body.