HORMONES AND ISD: TESTOSTERONE
Hormones play a role in numerous bodily functions, including sex. They also have an effect on mood and, more generally, how we feel about ourselves and life. When certain hormones arrive on the scene, they can really get things rolling. But other hormones can keep anything from happening at all. Although not the most common cause of ISD, lower-than-normal levels of the hormones thought to stimulate sexual desire, as well as unusually high levels of inhibiting hormones, can have a dramatic impact on sexual desire.
Certain hormones, testosterone in particular, apparently excite cell membranes in the brain, activating the circuits that trigger sexual desire. Thus, even though it is commonly thought of as the "male sex hormone," testosterone plays a role in the stimulation of sexual desire in both men and women.
Men with abnormally low testosterone levels suffer from ISD, including those who test at the low end of the normal range. Testosterone production gradually decreases in men during middle age and men over the age of forty who suffer from global ISD should have their testosterone levels checked by a physician. Giving testosterone to men with abnormally low levels of the hormone often increases sexual desire. However, the hormone will not increase desire in men whose testosterone levels are well within the normal range—so don't rush off to your doctor and ask for a prescription.
Although sexual desire in women is also affected by testosterone, unless they have been deprived of all sources of the hormone because their ovaries and adrenal glands have been removed, their ISD is unlikely to be caused by a testosterone deficiency. Testosterone injections or creams can increase a woman's sexual desire if she is deficient in this hormone, but because they can also produce increased facial hair and other "male" characteristics in women—as well as other, more dangerous side effects—such treatment should not be used casually.
Men's Health-Erectile Dysfunction