The Testosterone Blueprint

Men's Health · Hormones & Blood Tests

Your hormones & blood tests — what your symptoms are telling you

Fatigue, low drive, lost muscle, low mood — they often trace back to a handful of hormones. Here's what each one does, what happens when it's off, and how to check the numbers.

See where to get tested — UK · US · Worldwide ↓

Does this sound familiar?

The signs of a hormone imbalance

Low testosterone and related imbalances rarely announce themselves. They show up as everyday things easy to blame on age or stress:

Persistent fatigue & low energy
Poor, broken sleep
Low sex drive / weaker erections
Losing muscle & strength
Stubborn belly fat
Low mood & irritability
Brain fog & poor focus
Lost drive & motivation

One or two can be normal. Several together, lasting for weeks, are worth understanding — which starts with the hormones behind them.

The hormones, at a glance

What each hormone does — and what too low or too high looks like

The whole picture in one view. A single testosterone reading misses most of it.

Hormone
What it does
If it's too LOW
If it's too HIGH
TestosteroneTotal & Free
What it doesDrive, muscle, mood, energy, libido and bone strength. “Free” T is the usable part.
If too lowFatigue, low libido, weak erections, lost muscle, low mood, brain fog, belly fat
If too highUsually only from TRT or steroids: acne, irritability, thickened blood
SHBGSex hormone-binding globulin
What it doesA protein (made by the liver) that grips onto testosterone in your blood and decides how much is actually free to use.
If too lowCommon with obesity / insulin resistance — can mask a true shortage
If too highLess usable testosterone despite a “normal” total; symptoms persist
LH & FSHLuteinising & follicle-stimulating hormone
What it doesMessengers from the brain (pituitary) that tell the testes to make testosterone (LH) and sperm (FSH).
If too lowWith low T, points to a pituitary / brain cause (secondary)
If too highWith low T, points to a testicular cause (primary)
OestradiolOestrogen (E2)
What it doesMen need a little — it protects bone, mood, libido and brain function.
If too lowJoint pain, low libido, bone loss
If too highWater retention, low mood, irritability, breast tissue
ProlactinPituitary hormone
What it doesNormally low in men; mainly checked when testosterone is unexpectedly low.
If too lowRarely a problem when low
If too highSuppresses testosterone & libido, headaches — may flag a pituitary issue
ThyroidTSH
What it doesSets your metabolic “speed” — energy, weight and mood.
If too lowAn underactive thyroid mimics low-T: fatigue, weight gain, low mood
If too highOveractive: anxiety, weight loss, racing heart
Vitamin DActs like a hormone
What it doesSupports testosterone, energy and mood.
If too lowFatigue, low mood; linked with lower testosterone
If too highRare; only from very high supplement doses
Signs a level may be too lowSigns a level may be too highEducational only — not a diagnosis.

Why LH & FSH matter

How the signal works

Low testosterone can come from the testes themselves, or from the brain's signal to them. That's the difference between primary and secondary — and why a good test checks the signal too.

FEEDBACK LOOPBrainHYPOTHALAMUS & PITUITARYSignalLH & FSHTestesTESTOSTERONE
BrainHypothalamus & pituitary
SignalLH & FSH
TestesTestosterone
↑ Feedback loop — testosterone signals the brain to ease off
Low T + low LH/FSH → brain/pituitary cause (secondary)Low T + high LH/FSH → testicular cause (primary)

Reading the number

Testosterone: low, borderline or normal?

Most men start with total testosterone. UK guidance gives rough thresholds — but how you feel matters as much as the number.

Illustrative only — ranges vary by laboratory, age, time of day, units and assay. A result “in range” doesn't rule out a problem if you have symptoms. Always interpret with a doctor.
Sources: BSSM (2023) · Society for Endocrinology (UK) · NHS.

LowBelow 8 nmol/L (<231 ng/dL)
Borderline8 – 12 nmol/L (231–346)
Typical12 – 29 nmol/L (346–836)

If you want to check your levels

Where to get tested

Reputable at-home and lab services that test these hormones — compared at a glance, grouped by region.

Provider
What's tested
Sample
Results
United Kingdom
UKMedichecksMost complete
What's testedTotal & Free T, SHBG, LH, FSH, Oestradiol, FAI, Prolactin, DHEA-S
SampleFinger-prick / nurse
Results~2 days, doctor-reviewed
UKThrivaEasy to track
What's testedPersonalised at-home panels incl. testosterone & key markers
SampleFinger-prick
ResultsOnline, tracked over time
UKForthFlexible range
What's testedMale hormone & testosterone panels, basic to advanced
SampleFinger-prick
ResultsOnline with guidance
United States
USAEverlywellSimplest start
What's testedTestosterone & Men's Health (total T, cortisol, DHEA, estradiol)
SampleAt-home · telehealth
ResultsA few days · HSA/FSA
USAUlta Lab TestsBuild your own
What's testedTotal/Free T, SHBG, LH, FSH, E2, prolactin, DHEA-S, TSH & more
SampleLab draw
ResultsOnline, fast
USAmyLAB BoxFully at-home
What's testedAt-home testosterone testing kit
SampleAt-home
Results1–5 days · HSA/FSA
Worldwide · incl. Europe
WorldwideLetsGetCheckedNurse support
What's testedAt-home male hormone tests (testosterone & related markers)
SampleAt-home · many countries
Results2–5 days · 24/7 nurse
WorldwideCerascreenEurope-wide
What's testedAt-home saliva hormone tests — testosterone, cortisol, oestradiol & DHEA
SampleAt-home saliva · ships across Europe
ResultsOnline report

Affiliate links — we may earn a commission at no extra cost to you. Only providers we consider reputable are listed.

Why you can trust this guide

Honest, evidence-based, no hype

Built on officially recognised medical information — guidance from the NHS, the British Society for Sexual Medicine and the Society for Endocrinology. We explain what tests measure and what results can mean; we don't diagnose, and we never publish dosing or treatment protocols.

Affiliate disclosure: some provider links are affiliate links and we may earn a commission at no extra cost to you. This never changes which services we list — only ones we consider reputable appear here.

Written by M. Videika — about The Testosterone Blueprint. Educational only; not a substitute for advice from your doctor.

Can I have low-testosterone symptoms with a “normal” result?

Yes. If SHBG is high, your usable (free) testosterone can be low even when total looks normal — which is why a full panel beats a single number.

Do I need a doctor's referral to test?

No — the services above let you order privately online. But results are best interpreted with a doctor, especially if anything is borderline.

When should I take the test?

In the morning, when testosterone peaks. Because it fluctuates, a borderline result is often confirmed with a second morning sample.

Finger-prick or venous blood — does it matter?

Both can be accurate. A venous (nurse-drawn) sample is often preferred for testosterone to avoid contamination — especially if you use testosterone gels or creams.

How much does a hormone blood test cost?

It varies by provider and how many markers you check — from a single testosterone test up to a full panel. Prices differ by country, so check the current cost on each provider's site via the links above.

How do I prepare for the test?

Take the sample in the morning (ideally before 10am), when testosterone is highest. Many providers suggest being well hydrated and avoiding heavy exercise or alcohol the day before. Follow the exact instructions in your kit.

How long do results take?

Usually 1–5 working days depending on the provider. Results appear in a secure online account, and several services include a doctor's or nurse's comment on what they mean.

Which hormones should I actually test?

For a clear picture, a full male panel (total & free testosterone, SHBG, LH, FSH, oestradiol and prolactin) tells you more than testosterone alone. Adding thyroid (TSH) and vitamin D helps rule out other causes of the same symptoms.

Are at-home hormone tests accurate?

Reputable providers use accredited laboratories, so the analysis is reliable. The biggest variable is how the sample is collected — so follow the timing and technique instructions carefully, and confirm important results with a repeat test or your doctor.

Can young men have low testosterone?

Yes. While levels decline gradually with age, low testosterone can affect men of any age. If several symptoms persist for weeks, testing is reasonable regardless of your age.

What should I do if my result is low or out of range?

Don't panic, and don't start any treatment on your own. Take your results to a doctor — a single reading isn't a diagnosis, and they may repeat the test or look at the wider picture before advising anything.

What's the difference between total and free testosterone?

Total T is all the testosterone in your blood; free T is the small unbound portion your body can actually use. SHBG changes how much is free — which is why a “normal” total can still come with symptoms.

Not ready for a blood test?

Start with the free 2-minute Testosterone Test

A quick symptom-based read — no blood, no email required.