Low testosterone

What is low testosterone?

Low testosterone — clinically known as hypogonadism — occurs when the body produces insufficient testosterone to maintain normal physiological function.

In men, testosterone is produced primarily in the testes under the control of LH (luteinising hormone) from the pituitary. In women, smaller amounts are produced in the ovaries and adrenal glands, where testosterone supports energy, libido, muscle tone, and mood.

There are two clinically distinct forms, which require different investigation and treatment:

• Primary hypogonadism: the testes or ovaries fail to produce adequate testosterone despite normal or elevated pituitary signalling (high LH/FSH). Causes include genetic conditions, testicular injury, chemotherapy, and autoimmune damage.

• Secondary hypogonadism: the pituitary or hypothalamus fails to send adequate signals to the gonads (low LH/FSH). Causes include pituitary adenoma, hyperprolactinaemia, obesity, chronic illness, and opioid use. This is the more common form in adult men.

Distinguishing between the two is essential for correct diagnosis and treatment and requires measuring LH, FSH, and prolactin alongside testosterone.

When testosterone levels drop below the optimal range, you may experience gradual changes in energy, body composition, and mood, often without realising that hormones are playing a part.

Symptoms of low testosterone

Low testosterone symptoms develop gradually and overlap significantly with stress, poor sleep, and normal ageing, making blood testing the only reliable way to confirm deficiency. Common signs include:

• Persistent fatigue and low energy despite adequate rest

• Reduced libido and changes in sexual function

• Loss of muscle mass and strength

• Increased body fat — particularly visceral abdominal fat

• Low mood, irritability, or mild depression

• Cognitive difficulties — reduced concentration and mental clarity

• Poor sleep quality

• Reduced bone density — increasing fracture risk over time

• Slow recovery after exercise

In men additionally:

• Reduced facial and body hair

• Testicular atrophy in more advanced cases

• Fertility difficulties

In women, low testosterone contributes to fatigue, low libido, reduced muscle tone, and mood changes, often in the context of perimenopause or adrenal dysfunction.

Because these symptoms develop slowly, many people attribute them to ageing. This is why early testosterone testing is so valuable.

What causes low testosterone?

There are multiple factors that can lead to testosterone decline.

Common causes include:

• Age-related decline: testosterone falls gradually from the mid-30s in men; decline accelerates after 45–50.

• Obesity and metabolic syndrome: excess visceral fat converts testosterone to oestrogen via aromatase; insulin resistance suppresses gonadal function.

• Pituitary adenoma: a benign pituitary tumour can suppress LH and FSH, causing secondary hypogonadism; detectable on brain MRI.

• Hyperprolactinaemia: elevated prolactin suppresses LH and FSH, reducing testosterone; can be caused by a pituitary adenoma or medications.

• Chronic illness: diabetes, thyroid dysfunction, kidney disease, and liver disease all impair testosterone production.

• Medications: opioids, corticosteroids, anabolic steroids, and certain antidepressants suppress hypothalamic-pituitary-gonadal axis function.

• Chronic stress and poor sleep: sustained cortisol elevation suppresses testosterone production.

• Genetic conditions: Klinefelter syndrome (XXY) causes primary hypogonadism in men.

• Testicular injury, infection, or chemotherapy: directly impair testosterone-producing cells

By identifying lifestyle or medical contributors early, you can better support healthy hormone regulation.

Low testosterone is detected primarily through blood tests measuring the hormonal axis from pituitary to gonads, with brain MRI relevant when secondary hypogonadism is suspected.

Blood testsElfcare's panel includes a comprehensive male and female hormone profile:

• Total Testosterone: The primary marker, measured in the morning when levels peak.

• SHBG: A protein that binds testosterone; high levels can cause deficiency symptoms even if total levels seem normal.

• Bioavailable Testosterone: The "free" fraction that is actually accessible to the body; the most clinically relevant measure.

• LH & FSH: Pituitary hormones used to distinguish between testicular failure and pituitary dysfunction.

• Prolactin: High levels can suppress testosterone; often caused by a pituitary adenoma.

• HbA1c & Glucose: Markers for insulin resistance, which is closely linked to testosterone deficiency.

• TSH: Assessed because thyroid dysfunction directly impacts hormone production.

Brain MRI (Pituitary): If blood tests indicate secondary hypogonadism (low LH/FSH), our brain MRI is used to exclude structural causes, such as a pituitary adenoma.

Body composition analysis (AMRA®): Low testosterone drives increased visceral fat and reduced muscle mass. Elfcare's AMRA® body composition analysis quantifies these shifts with clinical precision, providing a measurable baseline to monitor health improvements.

Why early detection matters

Low testosterone rarely drops overnight; it typically declines gradually, impacting your focus, metabolic health, and muscle mass long before obvious symptoms appear. Detecting these shifts early allows you to address the root cause, whether it’s lifestyle-driven or a clinical condition like pituitary or thyroid dysfunction, before it becomes a chronic health issue.

Early detection empowers you to:

• Identify root causes: Rule out underlying issues like pituitary adenomas or thyroid imbalance.

• Protect long-term health: Reduce risks of cardiovascular disease, Type 2 diabetes, and osteoporosis.

• Preserve vitality: Address declines in mood, energy, and muscle health before they become clinically significant.

• Track trends: Monitor your hormonal baseline to make informed, data-driven lifestyle adjustments.

Understanding your levels early moves you from reacting to symptoms to proactively managing your long-term metabolic and mental well-being.

How Elfcare can help

Elfcare's blood panel includes total testosterone, SHBG, bioavailable testosterone, LH, FSH, prolactin, and metabolic markers — a complete hormonal profile that not only confirms deficiency but identifies whether it originates from the gonads or the pituitary. This distinction is clinically essential and is frequently missed when only total testosterone is measured.

Our brain MRI images the pituitary gland as standard — directly relevant when secondary hypogonadism is identified in blood results.

Our AMRA® body composition analysis quantifies the visceral fat and muscle changes most closely associated with testosterone deficiency, providing objective, measurable data beyond symptoms alone.

If our blood tests or MRI identify a suspicious finding, we take care of further diagnostics or refer you to the appropriate specialist.