Testosterone levels: what the numbers mean in Canada

What assessment involves, from symptoms to the search for a cause, is on the assessment page. This page is about the numbers on the lab report.

nmol/L and ng/dL

To convert, multiply nmol/L by 28.84 to get ng/dL, or multiply ng/dL by 0.0347 to get nmol/L. The figures below are rounded.

Many articles and AI answers quote American figures, such as "300 to 1,000 ng/dL" or "below 300 ng/dL". In Canadian units those are about 10.4 to 34.6 nmol/L and 10.4 nmol/L.

Reference ranges on Canadian lab reports

BC's testing protocol says reference ranges "are method and age dependent and are determined by each laboratory independently", and advises using the same lab for repeat tests. Dynacare splits its range by age; LifeLabs prints one adult range.

What counts as low

The Canadian guideline adds that "some patients may manifest symptoms" at higher levels, and treats the number as complementary rather than absolute. The BC protocol says testing is not recommended in men without symptoms, and that erectile dysfunction on its own is not a reason to test. Other thresholds, including the European Association of Urology's 12 nmol/L, are compared in the guide to diagnosis.

When and how to test

• Morning. The Canadian Urological Association specifies a draw between 7 and 11 am. BC says preferably before 10:00 am or within three hours of waking. In men aged 30 to 40, a 4 pm result can be 20 to 25% lower than an 8 am one, according to the American Urological Association.
• Fasting, depending on the guideline. The Endocrine Society asks for an overnight fast because food and glucose lower testosterone; Caronia 2013 found a 25% average drop after a 75 g glucose drink. BC says preferably fasting. The American Urological Association does not insist on it. The Canadian guideline does not address fasting.
• Repeat, depending on the guideline. The Endocrine Society and the American Urological Association ask for a second morning test on a different day. BC says two results can differ by up to 30%, and that a follow-up test is not needed if it would not change treatment.
• When well. BC advises against testing during an acute illness or hospital stay, after shift changes or with jet lag.

Free and bioavailable testosterone

Total testosterone is the first test. Free or bioavailable testosterone, calculated from total testosterone and SHBG (sex hormone binding globulin), is used when the total result is borderline: the Canadian Urological Association says it "can be determined to resolve equivocal total testosterone measures". In BC these values are calculated rather than measured, and the protocol limits them to cases where total testosterone is below the lab's lower limit and a question remains. LifeLabs BC prints a calculated free testosterone range of 115 to 577 pmol/L for men.

Testosterone and age

Testosterone falls slowly with age. The Massachusetts Male Aging Study measured a decline of about 1.6% a year in total testosterone in men aged 40 to 70, and 2 to 3% a year in bioavailable testosterone. Weight matters as well: in the European Male Ageing Study, men with a BMI of 30 or more had total testosterone about 5 nmol/L lower. Age-specific ranges are not standardized in Canada; some labs print one adult range and others split by age.

Levels on treatment

The Canadian Urological Association suggests aiming for the mid-normal range, a total testosterone of 14 to 17 nmol/L, measured mid-cycle for injections. BC's protocol times the draw by product: midway between injections or at the trough, two to eight hours after a gel or nasal dose, and three to five hours after a meal with fat for oral undecanoate. The full monitoring schedule is on the risks and monitoring page.

Common questions

What is a normal testosterone level for a man in Canada?

Canadian labs set their own reference ranges. LifeLabs in British Columbia and Ontario prints 8.4 to 28.8 nmol/L for adult men; Dynacare in Ontario prints 5.76 to 30.43 nmol/L under 50 and 5.41 to 19.54 nmol/L from 50; Alberta's provincial labs adopted 8.0 to 35.0 nmol/L in 2021. The Canadian testosterone cypionate monograph gives about 10.4 to 34.6 nmol/L (300 to 1,000 ng/dL) for young men.

What testosterone level is considered low in Canada?

There is no single number. The Canadian Urological Association guideline (2021) calls a total testosterone below 10 nmol/L a reasonable diagnostic threshold, while noting some men have symptoms at higher levels. BC's testing protocol puts the lower limit of normal at about 8 nmol/L in men under 30 and 6 nmol/L in men over 50. A low number supports a diagnosis only with symptoms and a look at the cause.

How do you convert testosterone from nmol/L to ng/dL?

Multiply nmol/L by 28.84 to get ng/dL, or multiply ng/dL by 0.0347 to get nmol/L. So 10 nmol/L is about 288 ng/dL, and the American cut-off of 300 ng/dL is about 10.4 nmol/L.

Should I fast before a testosterone test?

The guidelines differ. The Endocrine Society (2018) asks for a morning test after an overnight fast because food and glucose lower testosterone; one study found a 25% average drop after a glucose drink. BC's protocol says preferably fasting. The American Urological Association says the evidence is weak and does not insist on fasting. The Canadian Urological Association guideline does not address it. Follow your requisition and your clinician.

What time of day should testosterone be tested?

In the morning. The Canadian Urological Association guideline specifies a morning draw between 7 and 11 am; BC's protocol says preferably before 10:00 am or within three hours of waking. Testosterone is highest in the morning, and in men aged 30 to 40 an afternoon result can be 20 to 25% lower.