Why Your GP Won't Run a Proper Hormone Panel
If you go to your GP and say "I feel tired, low libido, struggling to build muscle, mood is flat" — there's a reasonable chance they'll run a basic blood test. That test will probably measure total testosterone, full blood count, and maybe thyroid function. If your total testosterone comes back anywhere in the "normal" range (8–35 nmol/L on most NHS labs), you'll be told everything is fine.
It isn't a complete picture. Total testosterone tells you roughly the same thing as knowing the engine size of a car without knowing whether the engine is running. The number that matters is how much of that testosterone is bioavailable — free and loosely bound to albumin, able to actually enter cells and do something. And that number depends on your SHBG (sex hormone binding globulin) and albumin — which the NHS panel almost never includes.
This guide covers the full panel you actually need, what the numbers mean, and how to get it done privately in the UK for under £100.
The Complete Male Hormone Panel
Total Testosterone
The starting point. Measures all testosterone in the blood — free, albumin-bound, and SHBG-bound combined.
NHS reference range: 8–35 nmol/L (varies slightly by lab) Functional optimal range for men: 18–30 nmol/L What "normal" actually means: The NHS range is derived from a population distribution including elderly men, unwell men, and men with lifestyle-driven low testosterone. Being "in range" at 9 nmol/L is not the same as being optimal.
Total testosterone in isolation is almost useless without SHBG.
SHBG (Sex Hormone Binding Globulin)
SHBG is a protein that binds to testosterone and makes it biologically inactive. High SHBG means more of your total testosterone is locked up and unavailable to cells. Two men with identical total testosterone of 18 nmol/L can have dramatically different free testosterone levels if their SHBG differs.
Reference range: 10–57 nmol/L What to aim for: 20–35 nmol/L is generally considered optimal What drives high SHBG: Liver conditions, hyperthyroidism, excess oestrogen, low insulin, ageing What drives low SHBG: Obesity, high insulin, hypothyroidism, anabolic steroid use
High SHBG with adequate total testosterone is a very common pattern in men over 40 who present with low testosterone symptoms but test "normal."
Free Testosterone
The fraction of testosterone not bound to SHBG or albumin — biologically active and available to cells. This is the number most predictive of symptoms.
Reference range: 0.2–0.62 nmol/L (or 200–620 pmol/L depending on lab units) Functional optimal: Upper third of range or above How it's calculated: Most labs calculate free testosterone from total T, SHBG, and albumin using the Vermeulen formula rather than measuring it directly. Direct free testosterone measurement is less reliable.
If your total testosterone looks reasonable but your SHBG is high, free testosterone may be low enough to cause symptoms.
LH (Luteinising Hormone) and FSH (Follicle Stimulating Hormone)
LH and FSH are pituitary hormones that regulate testosterone production. Including them in your panel distinguishes primary hypogonadism (the testes aren't producing testosterone properly) from secondary hypogonadism (the pituitary isn't sending the right signals).
LH reference range: 1.7–8.6 IU/L FSH reference range: 1.5–12.4 IU/L
Why this matters:
- Low testosterone + high LH = primary issue (testes problem)
- Low testosterone + low LH = secondary issue (pituitary/hypothalamus problem, potentially more treatable)
- Normal testosterone + high LH = compensated hypogonadism — the pituitary is working hard to maintain normal testosterone
This distinction informs treatment decisions significantly. A private TRT clinic will always want LH and FSH before prescribing.
Oestradiol (E2)
Testosterone converts to oestradiol through aromatase enzyme activity. Some oestradiol is essential for men — bone density, libido, cardiovascular function, mood. Too much causes: gynecomastia, water retention, low libido, mood instability, reduced morning erections.
Reference range for men: 41–159 pmol/L Functional optimal: 80–120 pmol/L When high E2 becomes an issue: Symptoms at levels above 150 pmol/L; most men feel best in the lower half of range
High body fat = more aromatase activity = more testosterone converting to oestrogen. This is one mechanism by which excess body fat suppresses available testosterone even when total testosterone is normal.
Prolactin
Prolactin is a pituitary hormone primarily associated with lactation in women but present in men. Elevated prolactin in men suppresses testosterone and can cause symptoms including low libido, erectile dysfunction, and sometimes nipple discharge.
Reference range: 86–324 mIU/L When to be concerned: Consistently above 400–500 mIU/L warrants further investigation
Causes of elevated prolactin: stress, certain medications (antidepressants, antipsychotics, metoclopramide), hypothyroidism, and — importantly — pituitary adenoma (a benign tumour on the pituitary). This is rare but significant.
Thyroid Panel (TSH, Free T3, Free T4)
Thyroid function and testosterone are deeply connected. Hypothyroidism increases SHBG, impairs testosterone production, causes fatigue, weight gain, and low libido — mimicking low testosterone so closely that the two are frequently confused.
TSH reference range: 0.4–4.0 mIU/L Functional optimal TSH: 1.0–2.5 mIU/L (many functional medicine practitioners consider TSH above 2.5 as potentially suboptimal even within range)
Always include Free T3 and Free T4, not just TSH. TSH can be normal while conversion of T4 to the active T3 is impaired.
Vitamin D
Not strictly a hormone panel marker, but Vitamin D functions as a steroid hormone precursor and Vitamin D receptors are present in Leydig cells (testosterone-producing cells in the testes). Deficiency is consistently associated with lower testosterone levels.
NHS deficiency threshold: <25 nmol/L Functional optimal: 100–150 nmol/L Reality in UK: A large proportion of men test significantly below optimal, particularly after winter months
Additional Markers Worth Including
HbA1c — Average blood glucose over 3 months. Insulin resistance and chronically elevated glucose suppress testosterone.
Full lipid panel — Cholesterol is the precursor to all steroid hormones including testosterone. Extremely low cholesterol (below 3.5 mmol/L) can impair testosterone synthesis.
FBC (Full Blood Count) and CMP — Baseline health markers. Anaemia can cause fatigue that mimics low testosterone.
Where to Get a Complete Panel in the UK
Medichecks — Best All-Round Option
Medichecks is the most comprehensive private blood testing service in the UK. Their "Male Hormone Blood Test" covers total testosterone, SHBG, free testosterone (calculated), oestradiol, prolactin, LH, FSH, and DHEA-S. Around £69–89 depending on current pricing.
Their "Advanced Well Man Blood Test" (around £199) adds thyroid, Vitamin D, HbA1c, full blood count, liver and kidney function, and full lipid panel — essentially everything on the list above in a single draw.
You can use home finger-prick collection or visit a clinic partner for a venous draw (better for accuracy on oestradiol and prolactin). Results arrive within 24–48 hours via their online portal, with a doctor's commentary on any flagged values.
Medichecks Male Hormone Test — affiliate link
Monitor My Health — Best for NHS-Comparable Results
Monitor My Health uses NHS-accredited laboratories, which means the reference ranges and methodology are directly comparable to what your GP would use. Useful if you want to take results to your GP or a private TRT clinic.
Their "Testosterone and Male Hormone Profile" covers the essentials at a competitive price point. Venous blood draw via their clinic network or NHS phlebotomy services.
Monitor My Health — affiliate link
Thriva — Best for Subscription and Repeat Testing
Thriva is structured around regular quarterly testing with trend tracking — useful for monitoring changes after starting a supplement protocol or TRT. Their male hormone packages cover the core markers.
Home venous collection kit, results in 48 hours.
What to Do with the Results
If total testosterone is below 12 nmol/L with symptoms: Discuss with your GP. This is diagnosable hypogonadism on NHS criteria. Getting NHS TRT is a long process but worth initiating.
If total testosterone is 12–18 nmol/L with symptoms and high SHBG: Your free testosterone may be low despite "normal" total testosterone. This is the most common underdiagnosed pattern. A private TRT clinic will evaluate this properly; most NHS GPs won't.
If free testosterone is in the lower third of range with symptoms: Lifestyle optimisation first (sleep, stress, body fat, foundational supplements — zinc, magnesium, Vitamin D). Retest in 3 months. If unchanged, discuss with a private clinic.
If oestradiol is high relative to testosterone: Body fat reduction is the primary intervention. Reducing aromatase activity through fat loss will improve the testosterone:oestrogen ratio meaningfully.
Interpreting Your Results: A Quick Framework
- Where is total testosterone? Below 15 nmol/L with symptoms = clinical territory. 15–20 nmol/L = worth optimising. Above 20 = look elsewhere for symptom cause.
- What is SHBG doing? High SHBG with borderline total T = low free T likely. Look at free testosterone.
- What is LH? High LH with low testosterone = primary issue. Low LH with low testosterone = secondary issue, investigate further.
- Is oestradiol proportionate? Above 150 pmol/L with symptoms = consider aromatase activity (body fat).
- Is thyroid contributing? TSH above 2.5 + fatigue + weight gain = thyroid may be driving symptoms.
- Is Vitamin D adequate? Below 75 nmol/L = supplement before doing anything else.
Getting this data costs less than a monthly gym membership. It changes what you do next from guessing to knowing.
The Short Version
Run a complete private panel through Medichecks or Monitor My Health. Include total testosterone, SHBG, free testosterone, LH, FSH, oestradiol, prolactin, thyroid (TSH, Free T3, Free T4), Vitamin D, and HbA1c. Under £100 for the core panel, under £200 for the comprehensive version.
Know your numbers before you buy a supplement stack, consider TRT, or assume you have a testosterone problem. The data takes guessing out of the equation entirely.