Why Your Testosterone Is ‘Normal’ but You Still Feel Terrible

You went to your doctor. You described the fatigue, the weight gain, the poor sleep, the diminished drive. Blood work was ordered. The result came back: testosterone 12.5 nmol/L. Within normal limits. Case closed.

Except nothing changed. You still feel the same.

This is one of the most common clinical scenarios in men’s health, and it stems from a fundamental misunderstanding of what “normal” means in the context of laboratory medicine.

The Problem with Reference Ranges

The reference range for total testosterone at most Ontario laboratories is approximately 8.4 to 28.8 nmol/L. This range is derived from the statistical distribution of testosterone levels across a large population of adult men, typically defined as the central 95 percent of values.

That population includes men aged 20 to 90. It includes men who are obese, sedentary, sleep-deprived, and insulin-resistant. It includes men with subclinical illness, chronic stress, and poor nutritional status. The range describes what is statistically common. It does not describe what is physiologically optimal.

A total testosterone of 12.5 nmol/L falls within this range. It is “normal” by statistical definition. But it is also a level that many 40-year-old men would be symptomatic at, particularly if their free testosterone and metabolic context tell a more concerning story.

Total Testosterone Is Only Part of the Picture

Testosterone circulates in three forms. Approximately 45 percent is bound to SHBG (sex hormone binding globulin), a protein that locks testosterone into a biologically inactive state. Another 50 percent is loosely bound to albumin and can become bioavailable under certain conditions. Only 1 to 3 percent circulates freely, unbound to any protein.

Free testosterone is the fraction that enters cells, binds androgen receptors, and produces the physiological effects associated with adequate testosterone: muscle maintenance, metabolic regulation, cognitive sharpness, libido, and mood stability. The distinction matters enormously.

A man can have a total testosterone of 15 nmol/L with an SHBG of 20 nmol/L and feel well. Another man with the same total testosterone but an SHBG of 55 nmol/L will have substantially less free testosterone available to tissues. His total testosterone is identical. His experience is entirely different. The second man’s free testosterone may be less than half that of the first, despite their total testosterone being identical on paper.

Without measuring both total testosterone and free testosterone (or at minimum SHBG to calculate it), the clinical picture is incomplete. This is not a nuance. This is the difference between a correct diagnosis and a missed one.

What Drives SHBG Up

SHBG rises with age, which partly explains why older men can have “adequate” total testosterone yet experience progressive symptoms. This is not arbitrary. As SHBG rises, the percentage of testosterone that is bioavailable falls, independent of total testosterone levels.

Beyond age, SHBG increases with hyperthyroidism, liver disease, low caloric intake, certain medications (particularly anticonvulsants and some antidepressants), and estrogen excess. SHBG decreases with obesity, insulin resistance, and hypothyroidism. The direction of SHBG change often reflects the direction of metabolic health.

A man with rising SHBG will see his free testosterone erode even if his total testosterone remains stable. Annual blood work that tracks only total testosterone will miss this entirely. This is the scenario where a man with “stable” total testosterone on repeat testing actually experiences progressive decline in free testosterone and worsening symptoms, yet is reassured that “nothing has changed.”

The “Optimal” vs “Normal” Distinction

Functional medicine operates with a different reference frame than conventional screening. The question is not “does this value fall within the 95th percentile of the general population?” The question is “does this value correspond to a state of health in which this specific patient functions well?”

For most men in their 30s and 40s, optimal total testosterone falls between 20 and 28 nmol/L, with free testosterone in the upper quartile of the reference range. These are the levels at which symptoms of deficiency are absent, recovery from exercise is robust, body composition is favourable, and cognitive and emotional function are stable.

A total testosterone of 12.5 in a 42-year-old is not a value at which most men thrive. It may be normal for the population. It is not optimal for the individual.

The Estradiol Variable

Testosterone is converted to estradiol by the aromatase enzyme, which is concentrated in adipose tissue. Men with higher body fat percentages, particularly visceral adiposity, tend to have higher aromatase activity and therefore higher estradiol relative to their testosterone. This is not a side effect. It is a physiological consequence of body composition.

Elevated estradiol in men can suppress LH production (further reducing testosterone), promote fluid retention, worsen breast tissue enlargement, impair libido, and blunt the subjective benefits of testosterone replacement. In men with insulin resistance, the pattern is particularly pronounced: elevated insulin drives visceral fat accumulation, visceral fat increases aromatase activity, aromatase converts testosterone to estradiol, elevated estradiol feeds back to suppress LH, completing the vicious cycle.

A man with a total testosterone of 14 nmol/L and an estradiol of 180 pmol/L is in a very different clinical situation than a man with the same testosterone and an estradiol of 90 pmol/L. The ratio matters. The metabolic context matters. Without measuring both, and without understanding the metabolic drivers of aromatase activity, the picture remains partial.

What Symptoms Correspond To

The symptoms of suboptimal testosterone are consistent and reproducible across patients:

Fatigue that is disproportionate to sleep and activity levels. Difficulty building or maintaining muscle despite consistent training. Accumulation of abdominal fat. Reduced mental clarity and verbal fluency. Irritability or emotional flatness. Declining libido and reduced quality of erections. Slower recovery from physical exertion. Diminished motivation and initiative.

These symptoms overlap with depression, hypothyroidism, sleep disorders, and chronic stress. A comprehensive assessment differentiates between them by measuring all relevant variables simultaneously rather than testing one axis at a time.

What Comprehensive Assessment Includes

At Manus Solis, testosterone evaluation includes total testosterone, free testosterone (calculated or direct), SHBG, estradiol, LH, FSH, prolactin, DHEA-S, a complete thyroid panel, fasting insulin, glucose, HbA1c, a full lipid panel, CBC with hematocrit, liver function, and PSA (for men over 40).

These markers are correlated with the patient’s symptom profile (Sensus) and physical function (Virtus) to determine whether intervention is warranted and, if so, what form it should take.

Treatment is not driven by a single number. It is driven by the convergence of how you feel, what your blood shows, and what your body can do.

The Titrate-to-Response Philosophy

Initiating testosterone therapy in a man with suboptimal levels is the beginning of the process, not the end. The correct dose is not a standard number. It is the dose at which the patient’s symptoms resolve, his bloodwork reflects safe and optimal levels, and his physical function improves.

This requires follow-up blood work at 8 to 12 weeks, symptom reassessment, and dose adjustment. Some men reach their target at a modest dose. Others require more. The protocol is individualized and iterative.

“Titrate to response” means the patient’s experience matters as much as the lab value. Neither is sufficient alone.

What You Can Do

If you have been told your testosterone is normal and you remain symptomatic, consider whether the assessment was complete. Was free testosterone measured? Was SHBG included? Was estradiol checked? Was the result interpreted against your age and symptoms, or only against the lab reference range?

A number without context is not a diagnosis.

Continue Reading

If you found this useful, these related articles may deepen your understanding:

• Signs of Low Testosterone That Men Often Ignore
• How Insulin Resistance Is Destroying Your Testosterone
• Why ‘Age-Appropriate’ Hormone Levels Are Flawed

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Dr. Handsun Xiao is a McGill trained physician (MD, CCFP) practicing functional medicine and bioidentical hormone therapy in Toronto, with virtual consultations available to patients across Ontario. He holds advanced BHRT certification through WorldLink Medical and IFM AFMCP training. Manus Solis offers physician led BHRT consultations with custom compounding through a dedicated Ontario pharmacy partner. To learn more or book a virtual consultation, visit manussolis.ca.