It is a myth that homosexuals have lower levels of testosterone says Dr. Heather Little-White

Heather Little-White, PhD, nutritionist and health expert

You may be wondering what is responsible for the sex drive in men. It is the wonder hormone testosterone, commonly referred to as the 'male hormone', as it rightly should be called. Testosterone and its biological effects are often oversimplified in an effort to explain social behaviour. It is well established that the males of the animal species develop and maintain aggressive and sexual gender-specific behaviour as a result of testosterone.

Functions

What are the functions of testosterone in males? Primarily, testosterone transforms the features of the body of a young boy in to that of a man. As such:

His voice deepens

Pubic hair grows

A beard develops

Shoulders get broad

Muscles develop

Sex drive is stimulated

He becomes aggressive, competitive and dominant.

It is in the testicles that testosterone is manufactured and as soon as adolescents start to pack in that 'stuff', physical changes are observed and the 'youth' starts to feel like a man. If testicles are castrated in the human male, there will be a noticeable difference in his sex drive. The process of sex-drive reduction will be slow and uneven according to researchers. Castration is proposed as a radical punishment for sex offenders but there are others who believe that a raging sex drive can be controlled by other methods. One that is commonly used for male sex offenders is giving them Depo-Provera, a synthetic female hormone which shuts down the production of testosterone and so controls the sex drive.

Erection

Although testosterone is considered a powerful hormone, there are limits to its capabilities. Contrary to what is believed, testosterone has little to do with a man's ability to get an erection. It may stimulate desire and his sexual fantasies but it has little to do with performance. A classic example is little boys with low testosterone levels, many of whom get erections quite often.

Men who suffer from erectile dysfunction and loss of libido are led to believe that this is as a result of a decline in testosterone levels as men age. Some men are given testosterone shots or pills but this practice in the absence of low testosterone is a disservice to men. According to Dr Richard Burger, professor of urology at the University of Washington, this practice of shots and pills actually shuts off its own production of testosterone. Testosterone injections given over a period makes it difficult for the body to recover and start producing its own supply again.

Prostate cancer

Further, giving testosterone to men with erection problems may be dangerous. Testosterone stimulates the growth of prostate tumours, so injections and pills place older men at risk for prostate cancer. It should be stressed, though, that testosterone does not cause prostate cancer but stimulates the growth of a pre-existing tumour. The only time that testosterone injections are encouraged is when a man's testosterone levels are very low as in the case of hypogonadism which is an under-functioning of the testes resulting in erection problems.

Women also benefit from the power of testosterone which also boosts their sex drive. In almost every other species, sex drive is only fuelled by female hormones which give them an interest in sex only at the time they are ovulating. The sex drive in male and female humans is driven by testosterone. Men have far more circulating testosterone compared to women which makes them more responsive to seductions.

Menopause

Women produce hormones in their ovaries but most of it comes from the adrenals which fuel women's sex drive into their later years even after menopause. When women complain of a lack of interest at menopause, they may be given replacement testosterone. When older women receive hormone replacement therapy, testosterone is combined with other hormones to boost libido and their sense of well-being. Testosterone is converted in the body to oestrogen, and it is thus possible that testosterone could compound the carcinogenic effects of oestrogen on the breast and the uterus.

There is very little data about the safety and long-term effects of testosterone supplementation in women. In a few instances, testosterone may trigger masculinity in women with features such as facial hair, deepening of the voice and weight gain through the bulking up of muscles. Side effects of testosterone supplementation can include rages or anger, voice deepening, acne, facial hair, weight gain and liver disease.

Homosexuality

It is a myth that homosexuals have lower levels of the male hormone when compared to heterosexuals. There is no research to support this argument as when homosexuals are given massive doses of testosterone their sexual preference does not change. All that may happen is that the homosexual may get a temporary boost in libido.

Testosterone is an amazing hormone but it should not be seen as a panacea to sex problems or as a love potion. It stimulates the sexual urges and plays a significant role in defining gender.