Could fatigue just be low T?

Sometimes, but rarely in isolation. Frank testosterone deficiency tends to come with libido changes, mood changes, slower recovery and reduced motivation, not pure tiredness. If the only symptom is fatigue and the panel is clean, the cause is elsewhere: most likely sleep, thyroid, mood or iron status.

Why doesn't this panel measure thyroid?

Thyroid (TSH, fT4) needs a different assay and is well-covered by GP panels. We don't want to charge you €89 for markers your GP will order for free. Run the two in parallel.

Salivary or serum cortisol is sometimes useful in suspected adrenal pathology, but the popular 'adrenal fatigue' framing is not supported by endocrine evidence. If you have symptoms that genuinely suggest Cushing's or Addison's, see an endocrinologist: a kit is the wrong tool for that.

Should I supplement testosterone if my level is on the low side?

No, not on the basis of one measurement and a symptom of fatigue. Re-test a borderline result with the same protocol, get the rest of the panel context, rule out thyroid and sleep, and only then have a real conversation about treatment. TRT for isolated fatigue with no other findings is overprescription.

← All symptoms◆ Persistent fatigue

Persistent fatigue in men: when it's hormones, when it's not

Persistent fatigue in men has a long differential: thyroid disease, anaemia, sleep apnoea, depression, vitamin D and B12 deficiency, and many others. Low testosterone is one cause, not the cause. A six-marker panel (Total + Free T, FSH, LH, SHBG, Prolactin, Estradiol) rules the hormonal piece in or out, but it does not measure thyroid, haemoglobin, or sleep architecture. Use the Hormone Panel 01 alongside, not instead of, a thyroid (TSH) check and a complete blood count (CBC) from your GP.

Most fatigue isn't low T. But for a slice of men, it is, and that slice is missable on a GP panel.

Order the panel →Take the 2-min quiz

Who this page is for

Men with months of unexplained tiredness (the kind that doesn't lift on weekends) especially with reduced motivation, slower recovery from exercise, and afternoon energy crashes. Less useful if your fatigue tracks neatly with sleep debt, an obvious life stressor, or a recent illness.

What's actually happening

Fatigue is downstream of so many systems that 'tired' on its own rarely points to one cause. What a hormone panel can tell you: whether your axis is suppressed (low T with low LH/FSH), whether you have testicular failure (low T with high LH/FSH), whether SHBG is hiding a functional T deficiency behind a normal-looking total, and whether prolactin is elevated enough to suppress everything else. What a hormone panel cannot tell you: thyroid status (TSH/fT4), iron and haemoglobin (CBC, ferritin), vitamin D, sleep apnoea, or depressive disorder. Run them in parallel.

Which markers explain it

TTestosterone
Total + free testosterone. Frank low T causes fatigue, low motivation, reduced libido, slower recovery and mood changes: typically in combination. Isolated fatigue with a perfectly normal total and free T is unlikely to be primarily hormonal.
Read the Testosterone brief →
SHBGSex hormone-binding globulin
Critical for interpreting the testosterone result. High SHBG (common in hyperthyroidism, advanced age, low calorie intake) raises total T but can leave free T inadequate. Low SHBG (common in insulin resistance) does the opposite and is itself a metabolic warning.
Read the SHBG brief →
PRLProlactin
Hyperprolactinaemia causes fatigue both directly and via axis suppression. It is one of the most missable causes on a standard GP panel because it is rarely ordered alongside testosterone. Persistent elevation needs imaging.
Read the Prolactin brief →

What to do next

Don't run this panel in isolation. Order it alongside a TSH, a CBC, a ferritin, and a 25-OH vitamin D from your GP (most GPs will order those for unexplained fatigue without a fight. The hormone panel covers the piece your GP probably won't order. Together, the two cover the high-yield part of the workup. If everything comes back clean and the fatigue persists, the next stop is sleep) particularly a screen for obstructive sleep apnoea.

When this is bigger than a kit

!Profound fatigue with unintentional weight loss: needs a clinician's evaluation, not a kit.
!Fatigue with new bradycardia, cold intolerance, hair loss: strongly thyroid; see your GP.
!Loud snoring and witnessed apnoeas: screen for obstructive sleep apnoea before any hormonal workup.
!Fatigue with persistent low mood and anhedonia: depression must be evaluated independently of any biomarker.

FAQ

Common questions before testing.

Order the Hormone Panel 01.

All six markers, one finger-prick, ISO-certified German lab. Physician review and a plain-language report in 3–5 working days.

Order the panel →Take the 2-min quiz

This page is informational and not a medical diagnosis. The Hormone Panel 01 is a screening test. For symptoms or out-of-range results, consult a licensed physician.