«I think my testosterone is low»: why symptoms alone are not enough

Real symptoms… but ones that apply to almost everything

Fatigue, lack of energy, a drop in libido, difficulties with erection, muscle loss, and mood changes can indeed appear when testosterone is low.

The problem is that these are catch-all symptoms. The very same ones produced by poor sleep, stress, depression, a sedentary lifestyle, excess weight, sleep apnea, thyroid issues, certain nutritional deficiencies, alcohol, or some medications.

That is why starting from symptoms alone and concluding 'this is a testosterone problem' is one of the most common mistakes I see. And it usually takes us down the wrong path.

So, what does a real deficit look like?

When we speak precisely, the testosterone deficit that truly matters (hypogonadism) requires two things at once: compatible symptoms or signs AND a confirmed low testosterone level in the blood. Neither symptoms alone, nor just a number on a piece of paper.

This distinction is the heart of everything. There are men with symptoms and a normal testosterone level; and men with a slightly low figure that is nowhere near the true source of their discomfort.

How to measure it properly (and why a single test is not enough)

Testosterone follows its own schedule: it is highest in the morning. So blood is drawn early, normally after fasting. So far, straightforward.

But there is a step that many people skip: a single low value is not enough. It must be confirmed with at least a second blood test, also taken in the morning and on a different day. Why such insistence? Because values fluctuate and can drop temporarily due to an infection, a bad night's sleep, or a stressful period.

To interpret it properly, we sometimes also look at other parameters — certain hormones from the pituitary gland and a protein that transports testosterone and determines how much of it is actually available. But the principle is simple: confirm before concluding.

Looking for the cause, not just the number

If there truly is a deficit, the work has only just begun: it is time to understand why. A problem with the testicle itself is not the same as a problem with the signals reaching it from the brain. That distinction changes the investigation, the approach, and sometimes brings to light causes that need to be addressed in their own right.

And there is something I like to remind patients of in the clinic: many of the factors that drive testosterone down are, to a large extent, reversible. Excess weight, sleep apnea, alcohol, poor sleep, or certain medications. Correcting them can improve the situation without needing anything else.

Why there is no need to rush into treatment

Testosterone treatment is not a trivial matter. It has specific indications, requires monitoring, and is not free of health effects and considerations. Starting it without a properly established diagnosis means exposing yourself to risks without any real benefit.

And there is one point I address separately because of how important it is: if you want to have children, external testosterone can reduce your fertility. This is something that always needs to be discussed before considering any treatment. (I have dedicated an entire article to it, because it deserves a calm, thorough explanation.)

If I could leave you with just one idea

Your symptoms matter and they need to be studied. But 'having less energy' is not the same as 'having low testosterone.' A correct diagnosis requires compatible symptoms and a confirmed low testosterone level on two morning blood tests, as well as identifying the underlying cause.

So if you recognise yourself in what I am describing, do not self-medicate or buy miracle solutions online. Get a proper evaluation and make decisions based on data. Sometimes the answer is a treatment; many other times, it is fixing something that was quietly undermining your health without you even knowing it.