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Testosterone is the big burly hormone, a guy’s guy. It’s actually found in both men and women but it is the primary male sex hormone. Testosterone is what we so often use to explain the illogical behaviour of guys.  Male levels of testosterone are 7-8 times the levels found in women. Their physiological effects impact on both behavior and physical appearance and is necessary for healthy living and wellbeing   Like oestrogens a lack of it can have a number of adverse effects including osteoporosis and the thinning and weakening of bones.

What does it do?

Produced and released from the testicles in males and the ovaries in women, testosterone contributes to a number of key developments during puberty:

  • Body odor (why you need to start showering more in your teen years)
  • Oily skin (zits)
  • Body hair
  • Increased sex drive (it makes you horny)
  • Growth spurt and muscle and bone growth and strength

In young guys specifically it encourages the development of:

  • The testis (balls)
  • Prostate
  • Facial and body hair
  • Broad shoulders and large rib cage
  • Adam’s apple and a deepening voice
  • Brow, jaw and chin growth (handsome chiseled features if it does its job right!)

In adult males it is necessary for healthy sperm development, the regulation of energy and the maintenance of muscle mass. Testosterone levels decrease with age.

Behaviour and Sex

Testosterone isn’t the only factor in a raving sex drive. However it has been shown low testosterone can reduce your ability to have satisfying sex. Lack of sex drive and erectile dysfunction are problems that can result from low testosterone. The smart guys still aren’t that sure about the connection between testosterone and the sex drive of men or women.
The internet is a little confusing on this with loads of confusing studies showing this, that and a pig’s ear about testosterone and sex but here are some interesting facts:

    Interesting facts

  • Studies show that testosterone levels in heterosexual men rise after just a brief conversation with a women. And the more flirting that occurs the larger the increase in testosterone
  • Men who watch a sexual movie have an average increase of 35% in testosterone, peaking at 60–90 minutes after the end of the film
  • Higher levels of testosterone in women tend to lead to better orgasms (no boys don’t go secretly spiking your girls smoothie with testosterone)
  • Testosterone and Behaviour

    Testosterone has always been associated with aggressive guy behavior. However there is little concrete proof of this. This is mostly as testosterone levels in the brain are difficult and risky to measure. Science has shown the high testosterones levels account for:

  • Risk taking behaviour
  • Increased competitiveness and desire for dominance
  • Increase in selfishness
  • Sex outside relationships (more likely to cheat)
  • Increase in anti-social behavior

Testosterone also decreases when a guy first falls in love with someone new or when they become a father. A Decrease in testosterone levels of new fathers is thought to cause emotional and behavioural changes that promote fatherly care.

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