What is a normal SHBG level in Canada?

Reference ranges vary by laboratory and sex. Most Canadian labs report approximately 10–57 nmol/L for adult men and 18–144 nmol/L for adult women, with the upper end of the range rising with age. Because assays differ between LifeLabs, Dynacare, and hospital labs, always interpret your result against the reference interval printed on your specific report rather than a generic online range.

How is SHBG different from total testosterone?

Total testosterone measures all testosterone in the blood — bound and unbound — while SHBG tells you how much of that testosterone is tied up and unavailable to cells. Two people with identical total testosterone of, say, 15 nmol/L can have very different amounts of active hormone if one has SHBG of 20 nmol/L and the other has SHBG of 80 nmol/L. Clinicians use both values together — often via the Vermeulen equation — to estimate free testosterone, which is the fraction that actually drives hormonal effects.

Can the birth control pill affect my SHBG levels?

Yes, significantly. Combined oral contraceptives containing ethinyl estradiol can raise SHBG 3–4 times above baseline, which substantially reduces free testosterone. For some people this contributes to low libido, vaginal dryness, or mood changes even while on the pill. Studies have found that SHBG may remain elevated for months after stopping oral contraceptives in a subset of users, though the clinical significance of this persistence is still debated.

Is SHBG testing covered by provincial health insurance in Canada?

In most provinces, SHBG is covered when ordered by a physician or nurse practitioner for a recognized clinical indication such as suspected androgen deficiency, PCOS workup, or monitoring of hormone therapy. Coverage rules differ by province — for example, Ontario's OHIP and BC's MSP each have their own listed indications — so it is worth confirming with your ordering clinician whether the test will be billed to your provincial plan or charged as a private lab fee, which typically runs $30–$60 out of pocket.

Can you lower high SHBG naturally?

Lifestyle changes can modestly reduce elevated SHBG when the underlying driver is metabolic. Improving insulin sensitivity through weight loss, resistance training, and reducing refined carbohydrate intake has been shown to lower SHBG by roughly 10–20% with a 10% reduction in body weight. However, if high SHBG is caused by hyperthyroidism, liver disease, or oral estrogen therapy, treating the root cause or changing the medication route (e.g., switching from oral to transdermal estradiol) is more effective than lifestyle measures alone.

Sex hormone-binding globulin — Glossary

What it is

Sex hormone-binding globulin (SHBG) is a liver-produced glycoprotein that binds testosterone and estradiol in the bloodstream, controlling how much of each hormone is biologically available to tissues — with roughly 40–70% of circulating testosterone bound to SHBG in healthy adults, rendering it inactive. Also called testosterone-binding globulin (TeBG), SHBG acts as a hormonal buffer: only the unbound ("free") fraction, typically 1–3% of total testosterone, can enter cells and exert biological effects. Because SHBG levels vary widely between individuals — and shift substantially with age, body composition, and medications — a normal total testosterone result can mask either a deficiency or an excess of active hormone, making SHBG measurement a standard part of hormone panels ordered through Canadian labs such as LifeLabs and Dynacare.

SHBG is produced primarily in the liver and, to a lesser extent, in the brain, uterus, and testes. Its concentration in blood is tightly regulated by competing hormonal signals: estrogens and thyroid hormone raise SHBG, while insulin, androgens, and growth hormone suppress it. Women typically carry SHBG levels roughly twice as high as men of the same age, and levels in both sexes rise with aging — a pattern that contributes to the functional androgen decline seen in older adults even when total testosterone appears within range.

Causes and mechanism

SHBG is a homodimeric glycoprotein encoded by the SHBG gene on chromosome 17. Each subunit contains a steroid-binding pocket with high affinity for dihydrotestosterone (DHT), testosterone, and estradiol, in that order of binding strength. Once bound, the hormone cannot interact with cellular receptors until it dissociates.

Factors that raise SHBG include:

Estrogen therapy (particularly oral estradiol and combined oral contraceptives, which can increase SHBG 3–4× above baseline)
Hyperthyroidism
Liver cirrhosis (early stages)
Aging
Anorexia or very low caloric intake

Factors that lower SHBG include:

Insulin resistance and type 2 diabetes
Obesity (especially visceral adiposity)
Hypothyroidism
Exogenous androgens (including testosterone therapy)
Glucocorticoid excess (Cushing's syndrome)
Polycystic ovary syndrome (PCOS) — a condition in which elevated insulin suppresses hepatic SHBG production, amplifying androgen activity

Condition	Typical SHBG direction	Clinical consequence
Oral estrogen / OCP use	↑↑ (up to 3–4×)	Reduced free testosterone; may worsen low libido
Obesity / insulin resistance	↓	Higher free androgens; PCOS phenotype amplified
Hyperthyroidism	↑	Apparent androgen deficiency despite normal total T
Testosterone therapy (injectable/topical)	↓	Free T rises more than total T suggests
Aging (men, after 40)	↑ ~1–2% per year	Progressive decline in bioavailable testosterone

Symptoms and diagnosis

SHBG itself does not cause symptoms directly; its effects are mediated through changes in free hormone levels. Abnormally high SHBG can produce symptoms of androgen deficiency — low libido, fatigue, reduced muscle mass, mood changes — even when total testosterone is normal. Abnormally low SHBG amplifies androgen activity and is associated with acne, hirsutism, and irregular periods in women, and with metabolic syndrome in both sexes.

SHBG is measured from a standard serum blood draw. Canadian reference ranges vary slightly by laboratory, but typical adult values are approximately 10–57 nmol/L for men and 18–144 nmol/L for women (ranges widen with age). Clinicians often use SHBG alongside total testosterone to calculate free testosterone using the Vermeulen equation, or to derive the Free Androgen Index (FAI = total T ÷ SHBG × 100). A low FAI in women (below ~1) suggests androgen deficiency; a high FAI (above ~5) is associated with hyperandrogenism.

Treatment options

SHBG is not treated in isolation — the goal is to address the underlying driver and, where appropriate, adjust hormone therapy to account for its effects.

Lifestyle modification: Weight loss and improved insulin sensitivity reliably raise low SHBG in people with obesity or metabolic syndrome. A 10% reduction in body weight can increase SHBG by 10–20%.
Route of hormone therapy: Switching from oral to transdermal estradiol avoids the hepatic first-pass effect and produces far smaller increases in SHBG — a clinically meaningful distinction for patients on menopause hormone therapy who report low libido.
Thyroid optimization: Correcting hypothyroidism or hyperthyroidism normalizes SHBG without additional intervention.
Testosterone therapy: In men with low bioavailable testosterone partly driven by high SHBG, testosterone replacement (available in Canada as topical gels, injections, or pellets) raises free testosterone; however, exogenous testosterone also suppresses SHBG further, which must be monitored.
Oral contraceptive choice: For women whose low libido is linked to OCP-driven SHBG elevation, switching to a progestin-dominant or non-oral formulation may reduce SHBG. This decision should involve a clinician familiar with contraceptive endocrinology.

When to see a clinician in Canada

Request an SHBG test — typically ordered alongside total testosterone, LH, FSH, and estradiol — if you are experiencing symptoms of hormone imbalance that are unexplained by total hormone levels alone, or if you are starting, adjusting, or discontinuing hormone therapy. In Canada, SHBG testing is available through provincial lab networks (LifeLabs, Dynacare, DynaLIFE in Alberta) and is generally covered under provincial health plans when ordered by a physician or nurse practitioner for a listed indication. Virtual hormone care platforms operating in Canada — including Felix, Maple, Cleo, Phoenix, and others — can order and interpret SHBG panels as part of a broader hormone assessment. If your SHBG is persistently abnormal despite lifestyle changes, referral to an endocrinologist or reproductive endocrinologist is appropriate.

Limitations and open questions

Research is still emerging on several aspects of SHBG biology. First, no universally agreed-upon reference ranges exist: Canadian labs use assay-specific intervals, and the same numerical result can be interpreted differently depending on the platform. Second, the Vermeulen free-testosterone calculation — widely used in clinical practice — is a mathematical estimate, not a direct measurement; equilibrium dialysis is more accurate but rarely available outside research settings. Third, SHBG has been identified as an independent biomarker for metabolic syndrome and cardiovascular risk, but whether low SHBG is a cause or a consequence of these conditions remains unresolved. Fourth, the long-term SHBG effects of newer hormonal contraceptives and gender-affirming hormone regimens are not yet fully characterized in large prospective studies. Health Canada has not issued specific guidance on SHBG target ranges for hormone therapy optimization, leaving clinicians to rely on international society recommendations and clinical judgment.

Sex hormone-binding globulin