Misdiagnosing Low Testosterone Symptoms in Men: The Real Story Behind Fatigue, Mood, and Motivation

Rick Miller
Jun 9
4 min read

Feeling flat? It might not be your testosterone — at least, not in the way you think.

Low Testosterone Symptoms in Men Is the New Catch-All Diagnosis — and It's Failing Us

Let’s set the scene.

You’re in your 40s or 50s.

You’re not sleeping great.

Your sex drive’s not what it used to be — in or out of the bedroom.

Workouts feel harder.

Belly fat creeps in.

You’re foggy, frustrated, and tired.

You Google your symptoms. You talk to a GP and the answer you get?

“Your testosterone must be low.”

Maybe it is.

But more often than not, this low testosterone symptoms in men diagnosis is partial at best, misleading at worst.

Here's why.

A vial of Delatestryl testosterone and a syringe on a wooden surface, with a blurred box in the background. The setting is dimly lit.

Total Testosterone Test Is Almost Useless on Its Own

Most men who get their "T" checked get a total testosterone blood test done — and nothing else.

But total testosterone alone tells us very little about:

How much bioavailable testosterone is actually doing its job
What’s binding or suppressing it (Sex Hormone Binding Globulin and insulin)
How the brain-hormone feedback loop is functioning

“You can have a ‘normal’ testosterone level on paper and still feel like rubbish. That’s why context matters and thats why our men excel with their hormone optimisation ”– Rick Miller, RD Founder, Miller Health

The Real Reasons Men Feel Low — and What to Actually Test

Let’s unpack what should be tested when a man feels fatigued, flat, or foggy:

✅ Total & Free Testosterone

Free testosterone is what really matters for libido, motivation, and muscle.
High SHBG or poor liver clearance? Your free testosterone plummets — even if total T is fine.

✅ SHBG (Sex Hormone Binding Globulin)

Often raised in stressed, overtrained, underfed, or thyroid-impaired men.
Too much SHBG = testosterone is locked away.

✅ LH and FSH (Pituitary gland signals)

Tells us if the brain is asking for more testosterone or not.
Low LH/FSH = central suppression = deeper issues (like light, stress, or trauma).

✅ Thyroid Panel

Low T3 or high reverse T3? You’ll feel exactly like low T — but it’s your metabolism that’s flatlined.

✅ Insulin and Fasting Glucose

High insulin crushes testosterone production.
Insulin resistance = low energy, high SHBG, mood swings.

✅ Inflammatory Markers (CRP, IL-6, Homocysteine)

Chronic inflammation = hormonal chaos.

✅ Sleep and Circadian Function

One week of poor sleep can cut testosterone by 15–30%.
Blue light at night? It’s not just ruining sleep — it’s shutting down your testosterone.

“Circadian mismatch is the most overlooked cause of low testosterone in modern men.

If you’re staring at a screen at 11pm, you’re telling your body not to reproduce.”– Dr Jack Kruse

Testosterone Is a Mirror, Not a Master Switch

Here’s the truth.

Primary hypogonadism (loss of testosterone production) is real and affects 5-10% of men (probably more) in most countries.

Male andropause is real, lowered testosterone levels in men >40 years of age.

We help our men with testosterone replacement therapy in London if they need it.

Miller Health is not a 'pay to play service for TRT" and low testosterone can often be a symptom and not always the root problem.

Better yet, if you are thinking or are currently using TRT

When you get the upstream factors right — light, food, sleep, stress, mitochondrial output — testosterone often fixes itself and you might need less medication.

But if you inject testosterone without fixing the system?

You might feel better at first… until the wheels fall off later or the amounts needed rise and rise.

Testosterone Optimisation: The Miller Health Way

At Miller Health in London, we run a comprehensive men’s hormone and performance panel, which includes:

✅ Total, free, and bioavailable testosterone

✅ SHBG, albumin, LH, FSH

✅ Full thyroid and insulin profile (optional)

✅ Inflammatory markers

✅ Redox and circadian rhythm review

✅ Resting metabolic rate and DEXA scan

We don’t guess.

We test.

And then we build a bespoke plan to help you actually feel better — not just push numbers and drugs based on an incomprehensive lab report

How This Changes Lives

Men come to me saying:

“I feel like I’ve lost my edge.”
“I’m still working hard but getting nowhere.”
“I thought TRT was the answer, but I still feel off.”

And after we test properly, we often find:

Their testosterone was fine — their thyroid was tanked.
They weren’t eating enough fat or protein.
Their RMR was suppressed by years of stress.
They were waking up in darkness, working under LEDs, and killing their circadian rhythm.

This is fixable. But only if we measure what matters.