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What to do About Low Testosterone

Many men are dealing with symptoms of suboptimal testosterone. But what’s causing it?

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Many men are dealing with symptoms of suboptimal testosterone. But what’s causing it?

What is testosterone?

Testosterone is what’s known as a steroid hormone. Men use cholesterol to make it in their testes, and women make in much smaller amounts in their ovaries. Some testosterone is also made in the adrenal glands.

Although testosterone is important to women’s hormonal function, this article will focus on testosterone (and specifically low testosterone) in men.

Where does testosterone come from?

It might be synthesised in the testes, but the production of testosterone also involves men’s brains. The pituitary gland (in the brain) releases something called luteinizing hormone. This hormone acts as a special messenger, travelling in the blood to reach the testes. When it gets there, it finds the Leydig cells and tells them to start making testosterone.

At the beginning of his life, a man has over 700 million Leydig cells in his testes. However, after his 20th birthday, he loses around 6 million of these cells yearly. This is one reason behind the lower levels of testosterone as a man ages—but, as you’ll discover, it’s not the only one.

What does testosterone do?

Most people understand that testosterone is key to creating a sense of ‘manliness’—and it’s true that its essential for both strength, libido and ability to perform in the bedroom.

However, testosterone influences many other bodily processes, such as [1]:

  • Bone growth
  • Stimulation of stem cells
  • Production of red blood cells
  • Memory
  • Liver function
  • Hair growth
  • Sebum (skin oil) production

For optimum health, it’s vital that a man sustains an appropriate level of this hormone throughout his life.

What are the symptoms of low testosterone?

Some of the symptoms of low testosterone seem obvious, while others are more subtle. Examples include [2]:

  • Erectile dysfunction
  • Decreased libido
  • Fewer morning erections
  • Low energy
  • Sleep disturbances
  • Depressed mood
  • Cognitive impairment

Low testosterone has also been associated with certain conditions. That’s not to say that low testosterone is causing these conditions, but that’s it’s more prevalent in people with these conditions. In some cases, it may even be a catch-22 situation (i.e. low testosterone can contribute to a condition, which then further lowers testosterone). Some examples include:

  • Diabetes. Low testosterone may be an early sign that a man is heading towards metabolic syndrome and/or type-2 diabetes [3].
  • Obesity. Several studies have found that low testosterone and obesity reinforce each other [4]. That means that if you address one, you’ll have knock-on effect on the other.
  • Depression. Another study showed that in a group of men with borderline-low testosterone levels, more than half had depression or depressive symptoms [5].
  • Osteoporosis. Due to its role in bone formation, an accepted symptom of low testosterone is a reduction in bone mineral density [6].
  • Cognitive decline. In older men, there’s a correlation between normal levels of testosterone and improved cognition [7].

Perhaps most significantly of all, low testosterone can significantly diminish a man’s quality of life. The psychological effects of symptoms—especially not being able to perform sexually as he would like—should not be underestimated.

What causes low testosterone?

Testosterone deficiency is on the rise. Figures vary, but it’s believed that more than 2% of men between the ages of 40 and 79 suffer from low testosterone [8]. That means there may be hundreds of thousands of men in the UK who are putting up with symptoms.

The conventional view is that testosterone deficiency is down to ‘primary hypogonadism’ or ‘secondary hypogonadism’. Primary hypogonadism involves the testes directly, and can be caused by conditions such as mumps, trauma or something called Klinefelter syndrome.

‘Secondary hypogonadism’ means there’s something amiss with the brain, thus affecting the messages than can travel to the testes. Amongst others, this could be a result of head trauma or pituitary tumour.

However, 89% of low testosterone cases don’t fit into this framework [9]. This means something else is going on.

Studies show that several lifestyle factors can contribute to low testosterone. These include:

Sleep loss

A lack of sleep dramatically reduces testosterone levels, even in healthy young men [10]. This effect can be seen after a week. It’s believed that up to a third of British adults are chronically sleep-deprived.


As levels of the stress hormone cortisol go up, testosterone goes down [11]. Stress can come in many forms: physical, emotional and even chemical. Which leads us to the next point…


Many commonly used drugs affect testosterone levels. These include opioids (painkillers), statins and tricyclic antidepressants. Nicotine, alcohol and marijuana also have an effect [12].


A high-calorie, low-nutrient diet—which is typical of many people in the West—can lead to a person becoming overweight and even obese. As you’ve learnt, obesity and low testosterone feed in to each other.


The traditional view was that testosterone naturally declined with age. However, more recent studies show that a quarter of men in later life maintain normal testosterone levels [13]. There appears to be a stronger correlation between comorbidities and low testosterone. In other words, the more health conditions you have, the more likely you are to have low testosterone.

Could it be that the same factors driving common lifestyle conditions (such as diabetes, obesity and cognitive decline) are also behind this global reduction in testosterone?

How to treat low testosterone

A key tenet of Functional Medicine is treating the individual. Rather than looking to balance hormones specifically, it’s best to help the person balance their lifestyle. This will allow their hormones to recalibrate naturally.

When it comes to supporting optimum testosterone, there are a few key principles:

Reach your optimum weight

Getting rid of excess weight can both raise testosterone and reduce your risk of metabolic conditions. When it comes to weight loss, different things work for different people—but a good starting point is to reduce your intake of white flour, alcohol and sugar.

Exercise intelligently

Studies consistently show that exercise supports testosterone levels. Both high-intensity sessions (such as HIIT) and weight training are good choices.

Reduce your toxic exposure

This particularly applies to cadmium, a toxin found in cigarettes, which has been found to reduce testosterone levels [14]. If you smoke, seek help to stop. If you live in a house with smokers, ask them to do it outside.

Manage stress

Remember, as cortisol goes up, testosterone goes down. We can’t always change the circumstances of our life overnight (job stress, for example) but we can change how we react to them. Try meditation, or practice mindfulness. This can also be good opportunity to evaluate your priorities.

Optimize sleep

Most people need between 7–9 hours a night. Invest in a comfortable bed, and give yourself time for a nightly wind-down routine.

Eat well

The foundations of a healthy diet are whole, natural foods. Beyond this, certain nutrients are particularly important for testosterone production:

  • Vitamin A and vitamin D [15]. These vitamins are found in liver, egg yolks, butter, cheese and oily fish. Vitamin D is also produced from exposure to sunlight.
  • Zinc [16]. This mineral is found in shellfish, red meat, legumes and seeds.
  • Selenium [17]. A mineral found in Brazil nuts and fish.
  • Supplement wisely. Certain supplements, such as quercetin and green tea extract, can stop the enzymes that convert testosterone into other hormones—therefore helping to maintain an appropriate level of testosterone.

It’s worth remembering that the cause of your low testosterone may be different to another man’s. As well as making changes to achieve a healthier, more balanced lifestyle, it’s worth speaking to a practitioner who understands hormones—as they’ll know how to deliver targeted support. For personalised support, please feel free to get in touch.


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