Testosterone: good or bad?

Exercise. (Reuters)

Exercise. (Reuters)

The first 10 results will include blogs where the writers wail about the low testosterone levels of “today’s men” and discuss the pros and cons of testosterone supplements, in between saying chest-beating things such as: 

“There’s a reason men rule the world. The only reason women have a say in things in modern times is because men allow them to have a say. Men are naturally stronger, faster, smarter and more reasonable than women.”

Like the rest of us, they’ve bought into the cliché that testosterone is the magic juice that makes man the aggressor. 

Aggression and criminality have long been associated with this hormone, but recently, researchers have begun to see that it’s just one factor among many — it’s not even the only hormone involved: female hormones seem to be important role players in the aggro game too.

But they’ve got one thing right: testosterone is the male hormone par excellence, made in that most masculine of bodily features: the testicles. 

And while there are natural ways to boost your testosterone levels a little, if you have a serious deficit, you will have to rely on supplementation testosterone replacement therapy (TRT). 

Testosterone is not exclusive to men; women need some testosterone to function too, and their ovaries and adrenal glands provide it, just as men need a bit of oestrogen. But it is testosterone that kicks in for boys at puberty to deepen the voice, trigger the growth of facial and body hair, build muscles along a male pattern and ramp up the sex drive.

Testosterone levels remain pretty high until about the age of 30, when they begin to decline naturally, and the slow downward trend eventually leads to symptoms that many men find disturbing. 

Loss of libido (sexual desire), erectile dysfunction, reduction in muscle mass, weight gain and even some loss of bone density have long sent worried men on a quest for solutions. 

So when recent research published in the Journal of the American Medical Association (JAMA) unexpectedly came up with a possible negative cardiovascular impact of TRT, it raised concerns with headlines such as “Testosterone drugs should warn of cardiac risk” and “New concern about testosterone and heart risks”. 

Together with an earlier study, it raised enough of a red flag to make the Food and Drug Administration institute investigate the risks of TRT. However, other scientists have leapt to the defence of the hormone.

Too little male hormone

But is there a testosterone crisis? The bloggers believe that modern man is suffering from a massive decrease in testosterone levels, which makes today’s men a bunch of wusses compared to their great-grandfathers. 

They speak of an “epidemic of low testosterone” and claim that men born in the 1970s have a “lower baseline of testosterone”. 

They’re not completely wrong. Research in both Finland and the United States (US) has shown a reduction in testosterone levels across all age groups that is more than you’d expect from simple aging.

The US research was published two years ago in the Journal of Clinical Endocrinology and Metabolism, with an accompanying editorial by Dr Shalender Bhasin (endocrinology, diabetes and nutrition, Boston University School of Medicine), who found the population level decline disquieting, and said it “is not explained fully by the usual suspects: increasing BMI (body mass index) and prevalence of obesity, certain other co-morbid conditions or decreasing incidence of smoking. 

“Although the analysis by Travison et al did reveal significant age-related increases in adiposity and medication use and a welcome decline in smoking, the age-matched decline in testosterone concentrations persisted even after adjusting for these variables.”

As well as being a consequence of low testosterone, obesity in itself can trigger reductions in the hormone, and many medications have a negative impact on a range of hormones. 

Oddly, some research has indicated that smokers have higher levels of testosterone than non-smokers, earning the bad habit a mention here.

Bhasin added,  “Although increasing adiposity and lifestyle factors that were recorded in the [Massachusetts Male Aging Study] it could not account for the secular trends in testosterone level, it is possible that other lifestyle factors, such as the increasing use of tight-fitting underwear, increasing room temperatures in American homes and offices during the past three decades, decreased physical activity with increased body mass indices and decreased smoking could have contributed to the declining testosterone levels in men.”

How seriously should we take the JAMA research showing that TRT raised the risk of heart attacks?

It’s not that solid, says Dr Craige Golding, an anti-aging physician in Johannesburg who is experienced in TRT treatment. He refers to a review of recent research on testosterone, including the JAMA study, which says that this research was poorly designed and doesn’t tell us much as a result. It’s in conflict with “numerous previous medical trials that show the beneficial effects of testosterone on the heart” and in fact, that “low testosterone levels in males are associated with an increased risk in the development of heart disease”.

So those who really need TRT should not be overly concerned about taking it — although some caution is indicated. Hypogonadism, or an abnormally low level of testosterone for your age, is not that common. 

The British Medical Journal (BMJ), notes that the European Male Ageing Study found that only 0.1% of men in their forties, 0.6% in their fifties, 3.2% in their sixties, and 5.1% of men in their seventies would be diagnosed as having hypogonadism.

And pushing the hormone up when it’s not called for could be a little risky, if a large Australian study published in November 2013 in the Journal of Clinical Endocrinology and Metabolism is anything to go by.

The study looked at the death rate (from all causes) among 3 690 men in Perth aged between 70 and 89, from 2001 to 2004, measuring both testosterone levels and levels of dihydrotestosterone (a potent androgen or male hormone). 

Men with a testosterone level in the middle range — neither too low nor too high — survived the longest.

“There is a trend, unfortunately, for men to be using testosterone to maintain their youth,” says Professor Demetri Constantinou, director at the Centre for Exercise Science and Sports Medicine at the University of the Witwatersrand. 

“It is being promoted to slow down the male ageing process and keep them (us) younger.” 

As is human nature, many men may think that if a little TRT is a good thing, a lot might be even better — to their detriment.

We interfere with the massive symphony of hormones at our peril; it is always worth taking a cautious approach, getting a thorough assessment done by a specialist who understands and keeps up with the science on testosterone and other hormones. But with that proviso, it seems that a tweak to your testosterone levels could be beneficial for heart health and general health.

This lifestyle health supplement is made possible by advertising support from Metropolitan Health, with agreed monthly themes. Contents and photographs were sourced independently by the M&G’s supplements editorial team.