What’s Causing an Epidemic of Low Testosterone?

Once dismissed purely as ‘midlife discontent’, the decline in testosterone among men is being measured, studied, and debated — even in those who are younger and otherwise deemed ‘healthy’.

Worryingly, these individuals outside of the usual stereotype are being diagnosed with testosterone levels far below what would have been considered normal for their age just decades ago. It raises the question: why is this happening?

In this article, Healf discusses testosterone as a product of biology and environment; influenced by diet and lifestyle, and, in some cases, even the air we breathe. We’ll also explore how it's generating a shocking decline in male fertility and what you can do about it.

Diet is arguably a major cornerstone when it comes to our health, and the impact of nutrition on hormone levels such as testosterone cannot be understated as a fact.

Nonetheless, ‘health-supporting’ dietary patterns have declined dramatically over the past century, with processed foods, artificial additives, and unhealthy fats running riot in our food industry. While a lot of men (and women) are concerned about what this is doing to their waistlines, these unhealthy foods also act to disrupt the body’s hormonal balance.

Highly processed foods, a culprit?

If you want to point out highly processed foods, think of those rich in refined carbohydrates and poor in micronutrients (such as mineral and vitamin content). It is a simple way to steer clear of them in the supermarket or restaurant.

Highly processed food causes both spikes and crashes in blood sugar levels, which you are likely to feel in your body if you are in tune with it. It is no secret that eating well makes you feel pretty good too.

What’s more, these rapid blood sugar movements promote chronic inflammation and insulin resistance, both of which can suppress testosterone production.

Insufficient Omega-3

Diets low in healthy fats (think your omega-3 fatty acids found in oily fish and minimally processed plant-based fats and oils) are likely to deprive the body of the building blocks needed to produce hormones.

After all, testosterone is synthesised from cholesterol, a substance that has been unfairly vilified in mainstream dietary advice. Trends such as low-fat diets may have inadvertently played a role in the decline of testosterone levels. That said, it is also good advice to check your macronutrient intake is in line with the unique needs of your body and to always ensure the highest quality products are being used.

Protein, the good kind

Another guilty culprit is protein quality. A lot of people are borderline obsessed with counting their daily protein intake, but the quality does count for a lot.

If you put this in the context of factory-farmed meats, for example, which are often pumped with hormones and antibiotics, they may negatively impact the body’s own hormonal regulation.

On the other hand, plant-based diets (when poorly planned, of course) can lead to deficiencies in zinc and vitamin B12, which are two nutrients critical for testosterone production.

The obesity crisis

Meanwhile, obesity, which has reached epidemic-like proportions, exacerbates the problem.

This can be down to a simple fact. Adipose tissue (body fat) produces an enzyme called aromatase, which converts testosterone into oestrogen. Therefore, the more fat a male body carries, the greater the likelihood of hormonal imbalance.

Physiologically speaking, testosterone production is regulated by the hypothalamic-pituitary-gonadal axis. This is a finely tuned system that is susceptible to a lot of disruption.

Stress

Take chronic stress, for instance, it’s a very well documented suppressor of testosterone. When the body is under stress, it prioritises the production of cortisol, a stress hormone, over testosterone.

Our modern environments, and modern lifestyles with their unrelenting demands, financial pressures, and incessant connectivity will keep many in a perpetual state of stress. And this unwittingly suppresses their testosterone.

Sleep

Sleep, or rather the lack of it, compounds the problem. Testosterone is primarily produced during REM sleep. This is a phase often cut short by poor sleep hygiene, late-night screen time, and conditions like sleep apnoea.

Research consistently shows that those who sleep fewer than six hours a night have significantly lower testosterone levels than their well-rested counterparts.

Movement

Be well aware that exercise, traditionally thought of as a testosterone booster, is also becoming a double-edged sword. While regular physical activity is beneficial, excessive endurance training or overtraining without adequate recovery can suppress testosterone.

In this way, many men, in their mission for fitness, unknowingly sabotage their hormonal health.

The environmental assaults

Environmental factors are perhaps the most insidious contributors. Those in the know about endocrine-disrupting chemicals (EDCs), ubiquitous in modern life, will be aware that they are wreaking absolute havoc on our hormonal health, not only for males but for all genders.

Found in plastics, pesticides, personal care products, and even drinking water, these chemicals mimic or interfere with the body’s natural hormones. Bisphenol A (BPA) is a common plasticiser that has been shown to reduce testosterone levels in laboratory studies.

Likewise, phthalates, used to soften plastics, and parabens, found in skincare products, are also very disruptive.

Toxicity through generations

Alarmingly, researchers are now finding that the exposure to these chemicals begins in the womb, with some studies linking prenatal exposure to lower testosterone levels in male offspring.

Air pollution and environmental toxins further compound this issue. Heavy metals like lead and mercury contaminate water supplies and food chains, and are known to be toxic to the testes. Even pesticides used in agriculture can have oestrogen effects. These diminish testosterone production in men who are exposed to them on a chronic basis.

Our lifestyles today, complete with endless drives and desk-bound office jobs are often completely at odds with the body’s natural needs.

Sedentary behaviour, now the norm for many working men, really has a profound impact on testosterone. This is because physical inactivity contributes to obesity and leads to a reduction in muscle mass. This combination is another key problem in testosterone production.

Muscle tissue is metabolically active and also plays a role in regulating hormone levels. It is easy to see how, when it’s lost, the body’s capacity to produce testosterone diminishes.

“After work drinks, anyone?”

Moreover, alcohol consumption and instances of recreational drug use further suppress testosterone. So, the occasional drink may not cause significant harm. But chronic or heavy consumption interferes with the liver’s workings to regulate hormones.

Some drugs, like opioids used in medical practices, are even more directly harmful, suppressing testosterone levels by interfering with the pituitary gland.

The link between testosterone and fertility is a delicate topic for some. However, testosterone is required physiologically for sperm production, and takes place in the testes. Therefore it is clear that, when testosterone levels fall, sperm quality and quantity often follow suit. This is one reason why male infertility is on the rise. And it’s a trend that parallels declining testosterone levels.

Sperm counts have plummeted by more than 50% in the last four decades, an astonishing statistic that should raise the alarm and call for action (some writers are even calling it 'Spermageddon').

The significance of testosterone for fertility

While low testosterone isn’t the sole culprit, it’s a significant piece of the puzzle.

This hormone influences the number of sperm produced and their motility and morphology, so, men with low testosterone often produce sperm that are less capable of reaching and fertilising an egg.

Beyond the biological mechanics, low testosterone can also affect libido and sexual performance, further complicating efforts to conceive. The psychological toll shouldn’t be underestimated either. Men struggling with fertility often experience a lot of stress and anxiety, which in turn can suppress testosterone. It is also a topic which, socially speaking, is ‘less ok’ to discuss compared to female fertility problems. And it makes the whole thing a vicious cycle that’s very difficult to break.

Reversing this apparent decline in testosterone requires a ‘hitting-it-from-all-sides’ approach.

What you can do for testosterone decline

On an individual level, men can make simple dietary changes, prioritising whole foods rich in zinc, magnesium, and healthy fats. Regular but balanced exercise, quality sleep, and stress management techniques like mindfulness can also help restore hormonal balance.

What society can do for testosterone decline

At large, on a societal level, there’s an urgent need for stricter regulation of endocrine-disrupting chemicals.

Creating an increased awareness could also play a role; educating men about the risks of poor lifestyle choices and the environmental factors that might be sabotaging their health.

Testosterone replacement therapy 

Testosterone replacement therapy (TRT) is increasingly popular, but it’s by no means a panacea. While TRT can alleviate symptoms of low testosterone, it doesn’t address the underlying causes. And, for many men, lifestyle and environmental changes may offer safer and more sustainable solutions.

The decline in testosterone is more than a personal health issue, and it is not limited to those in midlife either.

It’s a societal challenge with implications for our fertility, our mental health, and aspects well ingrained in our sense of wellbeing.

This is a conversation that needs to continue, we’re not just suggesting this in scientific circles but in homes, workplaces, and communities. The stakes, after all, are really not worth overlooking.

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