Total Testosterone
Also known as: Serum Testosterone
What Does Total Testosterone Measure?
Total testosterone measures the overall amount of testosterone circulating in the bloodstream, including both the bound and unbound (free) forms. Most testosterone in the blood is attached to proteins — primarily sex hormone-binding globulin (SHBG) and albumin — while only a small fraction (about 1-3%) circulates freely. The test reports the combined total of all these forms, expressed in nanograms per deciliter (ng/dL) or nanomoles per liter (nmol/L).
Why Does Total Testosterone Matter?
Testosterone is the primary male sex hormone, though it plays vital roles in both men and women. In men, it governs muscle mass, bone density, libido, sperm production, mood, and energy levels. In women, it contributes to bone health, sexual drive, and overall well-being. Abnormal testosterone levels can signal underlying conditions such as hypogonadism, polycystic ovary syndrome (PCOS), adrenal disorders, or pituitary dysfunction. Monitoring testosterone levels helps clinicians diagnose hormonal imbalances, guide hormone replacement therapy, and assess reproductive health in both sexes.
Normal Ranges
Males
300–1,000 ng/dL (10.4–34.7 nmol/L) for adult males aged 19–70+
Females
15–70 ng/dL (0.5–2.4 nmol/L) for adult females aged 19–70+
Children
Varies by age and pubertal stage; prepubertal children typically <30 ng/dL
Causes of High Levels
- Anabolic steroid or exogenous testosterone use — synthetic androgens raise total testosterone significantly above normal physiological ranges
- Polycystic ovary syndrome (PCOS) — one of the most common causes of elevated testosterone in women, driven by excess androgen production from the ovaries
- Congenital adrenal hyperplasia (CAH) — a genetic disorder causing the adrenal glands to overproduce androgens including testosterone
- Testosterone-secreting tumors — rare tumors of the adrenal glands or gonads can produce excess testosterone autonomously
- Early (precocious) puberty — abnormally elevated testosterone in children can trigger premature development of secondary sexual characteristics
- Ovarian hyperthecosis — excessive luteinization of ovarian stromal cells leads to markedly elevated androgen production in postmenopausal women
Causes of Low Levels
- Primary hypogonadism — damage or dysfunction of the testes (e.g., from injury, chemotherapy, or Klinefelter syndrome) reduces testosterone production directly
How to Improve Your Total Testosterone
Diet
- Consume adequate dietary fats including monounsaturated fats (olive oil, avocados) and saturated fats (eggs, grass-fed beef), as cholesterol is the precursor to testosterone synthesis
- Increase zinc-rich foods such as oysters, red meat, pumpkin seeds, and legumes — zinc is an essential mineral for testosterone production and regulation
- Eat cruciferous vegetables (broccoli, cauliflower, Brussels sprouts) regularly to help reduce excess estrogen levels through indole-3-carbinol metabolism
- Maintain a balanced caloric intake and avoid prolonged caloric restriction, which can suppress the hypothalamic-pituitary-gonadal (HPG) axis
- Minimize ultra-processed foods, refined carbohydrates, and alcohol consumption, all of which are associated with lower testosterone and increased inflammation
Supplements
- Zinc: 25–45 mg/day of zinc gluconate or zinc picolinate, particularly if deficient — shown to support healthy testosterone levels in men
- Vitamin D3: 2,000–5,000 IU/day, especially if deficient — vitamin D acts as a steroid hormone precursor and is strongly correlated with testosterone levels
- Ashwagandha (KSM-66 extract): 300–600 mg/day — clinical studies show it can increase testosterone by 10-22% and reduce cortisol, which suppresses testosterone
Related Biomarkers
Frequently Asked Questions
What is the difference between total testosterone and free testosterone?
Total testosterone measures all testosterone in your blood — both the portion bound to proteins (SHBG and albumin) and the small unbound fraction. Free testosterone refers only to the unbound portion (about 1-3% of total), which is biologically active and can enter cells to exert its effects. While total testosterone gives a useful overall picture, free testosterone is often more clinically relevant when assessing symptoms, because it reflects what your body can actually use. Someone can have normal total testosterone but low free testosterone if SHBG levels are elevated.
What symptoms suggest low testosterone in men?
Low testosterone (hypogonadism) in men can cause a range of symptoms including reduced sex drive, erectile dysfunction, fatigue and low energy, decreased muscle mass and strength, increased body fat (especially around the abdomen), mood changes such as depression or irritability, difficulty concentrating (brain fog), decreased bone density, and reduced body and facial hair. It's important to note that many of these symptoms are non-specific and can be caused by other conditions, so a blood test is necessary to confirm low testosterone levels.
What does high testosterone mean for women?
In women, elevated testosterone levels most commonly indicate polycystic ovary syndrome (PCOS), which affects approximately 10% of women of reproductive age. Symptoms of high testosterone in women include irregular or absent menstrual periods, acne, excess facial or body hair (hirsutism), thinning scalp hair (female pattern baldness), weight gain especially around the abdomen, and difficulty getting pregnant. Less common causes include congenital adrenal hyperplasia or androgen-secreting tumors. If you have these symptoms, consult your doctor for a full hormonal evaluation.