TESTOSTERONE ∙ 4 minute read

What causes low testosterone in young men?

By Luke Chapman | Medically reviewed by Dr Luke Pratsides

At some point, you’ve probably experienced extreme fatigue, a diminished sex drive, or generally feeling weak. Whilst there could be hundreds of reasons for this – ranging from lifestyle to physiological factors – we never really consider a lack of testosterone. 

It’s time to change that. 

Testosterone deficiency affects 20% of men aged 15-39, and that percentage increases for older age groups. It’s much more common than you realise, and it’s an often-ignored reason why men sometimes struggle with their mental and physical health.

It’s time to start recognising low testosterone and doing something about it. If you feel like you may have a testosterone deficiency, consider these symptoms:

  • Loss of libido
  • Decreased sexual performance
  • Reduced strength
  • Tiredness
  • Lack of energy 
  • Frailty 
  • Depression 
  • Mood change

Just a small drop in testosterone can have a huge impact on how you feel. But what causes that drop? 

There are many external factors that can influence your testosterone levels, such as hypogonadism, obesity, diabetes, anabolic steroids, or illicit drug use. Each one has a varying impact on how much testosterone you produce and the effect it has on the body.

Let’s get into it.


Hypogonadism refers to reduced function in the gonads, which leads to decreased testosterone levels. The most common symptoms are reduced libido and erectile dysfunction – if you’re struggling with your sexual experience, that could be the reason. Get your testosterone levels checked and discover the cause.

If you have hypogonadism, the most effective treatment is testosterone replacement therapy (TRT). Restoring your testosterone levels often leads to a heightened sex drive and can enhance your sexual experience.


Obesity can cause low testosterone and low testosterone can cause obesity. It’s a vicious cycle that’s hard to escape. Fat around the belly is metabolically active and converts testosterone into female sex hormones, oestrogens, meaning someone with a waist circumference greater than 102 cm (40.2 inches) is at high risk of developing testosterone deficiency. The combination of low testosterone and obesity creates a constant cycle of metabolic issues and can have detrimental effects on your mental health. 

TRT is considered as a possible option for treating low testosterone in obese men, but there is a more effective solution – weight loss. By losing weight, your body naturally produces more testosterone

Alongside increased testosterone, weight loss unlocks positive changes to your mental and physical health.


If you have type 2 diabetes, you’re twice as likely to have low testosterone levels. That’s a huge difference. Get checked out if you’re experiencing a reduced libido, lack of energy, erectile dysfunction, reduced body mass, or depression. 

An effective treatment for diabetics with low testosterone is TRT. Not only can it increase your testosterone levels, it can also reduce insulin resistance and improve glycaemic control. The treatment can sometimes lead to remission in men. If you have type 2 diabetes and low testosterone, TRT is the obvious choice. 

Anabolic steroids

Steroids are associated with large muscles and a ripped physique, but oftentimes they have an adverse effect. Steroid abuse disrupts the normal production of hormones in the body, leading to decreased sperm production and lowered testosterone levels. If you notice symptoms of low testosterone and you take steroids, consult with a doctor immediately.

Once you’ve stopped, your testosterone levels should gradually return to normal. 

Illicit drug use

Substance abuse is bad for you, but you already knew that. What you probably didn’t know is the impact it has on your testosterone levels. 

Opioid abuse often leads to decreased testosterone levels. The most common symptom is a reduced sex drive, which can also negatively impact your sexual experience. 

Your testosterone levels will most likely return to normal once you've ceased the use of substances.

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Testosterone Blood Test.

Be you again.

The numan take

Escape the menace of low testosterone. Instead of ignoring a lack of energy or reduced libido, get checked out. Once you’ve established the cause, consider the solutions and feel full of life again.