Updated 15 May 2013

Teens decoded

Some of the the real reasons for the moods, pimples and late nights.


Teenagers can be weird creatures. They slam doors, burst into tears at the drop of a hat and get spots just when they want to look their best. But considering all the hormones and chemicals surging through their bodies their behaviour is actually quite restrained.

Are hormones to blame when you suffer from teen angst, get spots just before a big night out or even battle to get out of bed in the morning?

If you understand what’s going on in your body it may help you realise why you are the way you are. It could also help you cope with certain things – such as getting those dreaded spots.

You’re exposed to mankind’s unique hormonal magic potion for the first time between the ages of six and eight. That’s when the adrenal glands at the top of the kidneys start secreting androgens. Androgens are just the start of the flood of hormones you’ll be exposed to.

Together they form a complex, sensitive system in which one hormone’s level determines another’s or triggers the secretion of another. At the age of about 10 for girls and 12 for boys the androgens in your body reach a level high enough to produce underarm and pubic hair, make your skin oilier and cause acne.

They’re also responsible for that nasty teen-specific smelliness that happens when you perspire and don’t bathe regularly.

Hormone attack
Androgen is followed by gonadotropin, a hormone that stimulates the sexual glands. Over the next year or two the level of gonadotropin in the blood increases sharply. This leads to the secretion of further hormones by the pituitary gland in the brain, which switches on the ovaries (in girls) and testes (in boys).

At this point you’re not fully formed yet but you are knee-deep in puberty and as you get deeper even more hormones are released. Ovaries produce oestrogen and progesterone. Testes produce testosterone. A teenage boy’s testosterone levels increase quickly to adult levels – 50 times higher than before, which is an enormous hormonal explosion.

And then parents wonder why a boy of 13 or 14 sometimes behaves strangely. It’s oestrogen that causes girls’ breasts to grow. It also determines a young woman’s shape through the redistribution of body fat.

Fat is now stored on girls’ hips. (Gee thanks, hormones!)

Testosterone takes charge of boys’ body shape: baby fat gives way to muscle and hair appears in unexpected places for the first time.

Eventually girls experience their first menstruation and boys their first full erection and ejaculation. This is the point at which you sometimes fall head over heels in love and the slightest touch, or even just a wink, from that special person has your heart skipping a beat.

The hormone mystery
Professor Steven Hough, a specialist in endocrinology (the study of hormones) at the University of Stellenbosch’s health sciences faculty, says scientists are still puzzled by what triggers hormone secretion. It’s thought that the nervous system, social and psychological factors, as well as your diet, all play a role.

It’s generally accepted children today start puberty at an earlier age. In 1850 girls got their first period at 17. Today it’s happening at 12.

A better diet, general prosperity and better medical care could be reasons for this. Being overweight can also cause you to start developing earlier. Many people believe hormones have just as dramatic an effect on the behaviour of teenagers as they do on their body shape.

Parents talk about “hormones on legs” and complain about their teen kids’ fickle moods, impulsive behaviour and over-emotionality. It appears young people crave excitement and enjoy wild behaviour.

Statistics bear this out, Vivienne Parry writes in her book The Truth About Hormones (Atlantic Books, 2005). Accidents and thrill-seeking cause over three quarters of teen fatalities. The sturm und drang years (years of storm and longing), some call them.

But whether hormones are to blame when you sneak out of the house at night to go to a partyis open to debate.

In the past it was believed the brain was fully developed by adolescence but new research shows biological adulthood is reached only by the late teens and early twenties. During teendom the nerve endings in the forebrain are “pruned” to make them more effective.

This explains why thought processes such as goal setting, establishing priorities, organisation and impulse control develop only later on.

“Hormones can’t get all the blame for teenage behaviour. It’s not just testosterone that’s responsible for dangerous behaviour but also the inability of an immature brain to perceive and evaluate risky behaviour,’’ Parry writes.

When it comes to sexual behaviour she compares the immature brain to a speeding car without a driver. Adolescent girls have the hormones and figures of adult women, while testosterone causes an adolescent boy to think of sex every six seconds – and this while the brain’s reasoning ability is still under construction.

Sleep is essential
Hormones are the culprits when it comes to your sudden desire to sleep all the time, though. A subtle shift in your sleep patterns occurs during puberty – the accelerated growth phase you go through during adolescence apparently requires more sleep.

This is partially explained by an increase in levels of melatonin (the sleep hormone) in teens’ blood. When that alarm goes off at 7 am your body thinks it’s still four in the morning.

Many teenagers get too little sleep in the long term, which leaves them with the same symptoms as jet lag.

Young people need nine hours of sleep a night but if you’re like most teens you won’t feel tired until the early hours of the morning.

Researchers say this is normal: teens’ circadian rhythms cause them to become sleepy only at around 2 am and to want to sleep till 11 am.

Dr Steve Delport, an endocrinologist and the father of two sons who’ve already been through puberty, says there’s nothing unusual about it. “Puberty is a normal period of growth and should be treated as such.

Talk about puberty
Much of the teen behaviour that makes parents want to climb the walls can be prevented if they give their children the correct facts about puberty and talk to them about it regularly.

“Parents wrongly think their children are now grown up and therefore entrust them with responsibilities they’re not ready for,” Dr Delport says. (It’s good to know your parents aren’t always right!) “Teenagers need their parents’ support and advice now more than ever to be able to cope with peer pressure and body changes.”

Your self-image changes along with your body during your teens. That’s why you spend hours in front of the mirror and often feel self-conscious. Your parents need to know it’s normal for you to want to be alone a lot during this time.

Dr Delport also points out the genders differ markedly when it comes to maturation markers. Teen girls’ fast-growth phase starts when they’re around 12 but with some girls it starts at 10 or even earlier.

In boys the fast growth phase starts around 14 and sometimes even later. When puberty is delayed it can be a serious phenomenon that may require medical help.

“In most cases a large dose of patience is all that’s required but sometimes children need medical attention,” Dr Delport says.

(This is an edited version of a story that originally appeared in YOU Pulse / Huisgenoot-POLS magazine, Autumn 2008.)

Read more:
Female growth milestones during puberty
Male growth milestones during puberty
Spots - and how to deal with them

Questions?  Ask the Teen Expert 


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