Total Testosterone
Total testosterone measures the combined protein-bound and free fractions of the main male sex hormone, which supports muscle mass, bone density, libido, mood, and erythropoiesis. Low levels are common with aging, obesity, and chronic illness and can cause fatigue, low libido, erectile dysfunction, and depression. Morning fasting measurement is preferred because levels vary diurnally.
Units: ng/dL; some labs report nmol/L (nmol/L = ng/dL × 0.0347). Check the units on your report before comparing to any range here.
Optimal range: who says what
Institutions, researchers and practitioners draw the line in different places. Each position is listed with who holds it and, where a document states it, a link. How we verify ranges.
- Institution or studyTherapy considered below ~300 ng/dL with symptoms; harmonized lower limit ~264 ng/dL for young menEndocrine Society clinical practice guideline (2018)
- Institution or study264-916 ng/dL (men 19-39)Harmonized reference range (Travison et al. 2017, four US and European cohorts)Healthy nonobese men; the harmonized median was 531 ng/dL
- Institution or studyBelow 213 ng/dL (7.4 nmol/L) carries higher all-cause mortalityIndividual-participant meta-analysis (Yeap et al. 2024, Ann Intern Med)Cardiovascular mortality was higher below 153 ng/dL (5.3 nmol/L)
- Named practitionermen 700-1100 ng/dL (Quest) or 600-900 (LabCorp) / women 28-60 ng/dLLife Extension · Lab Testing Protocol (Suggested Optimal Ranges)Disclosure: Life Extension sells lab panels that appear in our blood-test comparisons.
- Lab reference intervalMen: 300-1000 ng/dL, Women: 15-70 ng/dLWhat a lab report flags against. A lab interval is not an optimal target.
Practitioner targets are individual positions, often tighter than guideline ranges. Each was checked against its article before publishing.
17 of 21 itemized panels
Sex Hormones (Male)
What is Total Testosterone?
Total testosterone measures the combined amount of free (unbound) and protein-bound testosterone in your blood. Testosterone is the primary male sex hormone, but it's critically important for both men and women. In men, it's produced primarily in the testes, while women produce smaller amounts in the ovaries and adrenal glands. Testosterone is essential for muscle mass, bone density, libido, energy, mood, cognitive function, and metabolic health.
Testosterone declines with age in men, and population levels have also fallen across generations independent of age (Travison 2007). Low testosterone is associated with loss of muscle, more body fat, lower bone density, lower libido, and fatigue. Whether age-typical levels are adequate is debated; targets from named sources are listed in the ranges section.
Total testosterone includes both free testosterone (2-3% of total, biologically active) and bound testosterone (bound to SHBG and albumin, less active). If total testosterone is low-normal but SHBG is high, free testosterone may be inadequate. This is why checking free testosterone or calculating the free androgen index is important alongside total testosterone.
Why Total Testosterone Matters for Longevity
- Muscle mass and strength: Testosterone is THE primary driver of muscle protein synthesis. Low T accelerates age-related muscle loss.
- Bone density: Testosterone (converted to estradiol in men) maintains bone mineral density. Low T increases fracture risk.
- Metabolic health: Low testosterone is strongly associated with insulin resistance, type 2 diabetes, visceral fat accumulation, metabolic syndrome.
- Cardiovascular health: Contrary to old beliefs, physiologic testosterone levels are protective. Low T increases CVD risk in men.
- Cognitive function: Testosterone supports memory, spatial ability, and may protect against cognitive decline and Alzheimer's.
- Quality of life: Libido, energy, motivation, mood, and sense of well-being are all testosterone-dependent.
Interpretation bands (curated, PMID-backed)
Holder: OptimizeBiomarkers editorial synthesis of: Clinical review: Endogenous testosterone and mortality in men: a systematic review and meta-analysis (Araujo et al., 2011); Systematic review and meta-analyses on associations of endogenous testosterone concentration with health outcomes in community-dwelling men (Marriott et al., 2021); Serum testosterone and short-term mortality in men with acute myocardial infarction (Militaru et al., 2010). No single paper sets these cutoffs; for attributed targets see who says what.
Optimal (Men)500-900 ng/dL▼
- Optimal range for men
- Higher end associated with better muscle mass, energy, libido
- Functional medicine often targets 600-800 ng/dL
Optimal (Women)30-70 ng/dL▼
- Optimal range for women
- Too low causes fatigue, low libido, muscle loss
- Too high can cause virilization (facial hair, acne, voice changes)
Low (Men)<300 ng/dL▼
- Possible hypogonadism in men
- The Endocrine Society guideline (2018) considers testosterone therapy below about 300 ng/dL when symptoms are present
- Can cause fatigue, low libido, muscle loss, depression
Low (Women)<15 ng/dL▼
- Low testosterone in women
- Causes fatigue, low libido, difficulty building muscle
- Consider DHEA supplementation or low-dose testosterone
- Clinical review: Endogenous testosterone and mortality in men: a systematic review and meta-analysis.
- Systematic review and meta-analyses on associations of endogenous testosterone concentration with health outcomes in community-dwelling men.
- Serum testosterone and short-term mortality in men with acute myocardial infarction.
What raises or lowers Total Testosterone
Causes of high Total Testosterone
- Exogenous testosterone use (TRT, anabolic steroids).
- Testicular tumors: Leydig cell tumors produce excess testosterone.
- Adrenal tumors: Androgen-secreting adrenal carcinomas (rare).
- PCOS in women: Insulin resistance drives ovarian androgen production.
- Congenital adrenal hyperplasia: Enzyme deficiency causes androgen excess.
- Ovarian tumors in women: Rare androgen-secreting tumors.
Causes of low Total Testosterone
- Primary hypogonadism (testicular failure): Klinefelter syndrome, chemotherapy, radiation, mumps orchitis, trauma, anabolic steroid abuse (suppresses natural production).
- Secondary hypogonadism (pituitary/hypothalamic failure): Pituitary tumor, Kallmann syndrome, chronic opioid use, glucocorticoid excess, obesity.
- Aging: Levels decline gradually with age.
- Chronic illness: Chronic kidney disease, liver cirrhosis, HIV/AIDS, type 2 diabetes.
- Medications: Opioids (most significant), glucocorticoids, ketoconazole, spironolactone, GnRH agonists.
- Sleep apnea: Hypoxia suppresses testosterone production.
- Obesity: Fat tissue converts testosterone to estrogen via aromatase enzyme.
Symptoms when Total Testosterone is high or low
When high
- Acne, oily skin
- Increased facial/body hair (women)
- Male-pattern baldness (women with high T)
- Aggressive or irritable mood
- Irregular menstrual periods (women)
- Infertility in women
- Deep voice (women, irreversible)
- Increased red blood cell count (high hematocrit)
- Testicular atrophy (if using exogenous testosterone without HCG)
High testosterone in men >1000 ng/dL may indicate exogenous use or tumor. In women >100 ng/dL, evaluate for PCOS or adrenal disorder.
When low
- Fatigue, low energy despite adequate sleep
- Decreased libido, erectile dysfunction (men)
- Loss of muscle mass, difficulty building muscle
- Increased body fat, especially abdominal
- Reduced bone density, increased fracture risk
- Depression, low mood, irritability
- Cognitive decline, poor concentration
- Loss of morning erections (men)
- Gynecomastia (breast development in men) due to T→estrogen conversion
- Hot flashes (women)
- Irregular or absent periods (women)
Low total testosterone in men <300 ng/dL = hypogonadism. In women, <15 ng/dL may cause fatigue and low libido.
How to move Total Testosterone
Effect sizes (how much something moves the marker) appear only where the paper cited under the item states them. Talk to your clinician before starting or changing any medication or supplement.
Testosterone Replacement Therapy (TRT) for Low T in Men
- Testosterone cypionate or enanthate injections: 100-200 mg every 7-10 days (most effective). Maintains stable levels.
- Testosterone cream/gel: Daily application to shoulders/upper arms. Convenient but variable absorption. Risk of transfer to partners/children.
- Testosterone pellets: Implanted subcutaneously every 3-6 months. Stable levels but requires minor surgery.
- Goal: Resolve symptoms with testosterone at the level your clinician targets. Positions differ: Life Extension suggests 600-900 ng/dL on LabCorp assays (see who says what above). Monitor hematocrit, PSA, estradiol.
Lifestyle Optimization (Men and Women)
- Resistance training: Raises testosterone acutely after a session. Heavy compound lifts (squats, deadlifts, bench press) 3-4x/week.
- Adequate sleep: 7-9 hours nightly. One week of restricted sleep lowered testosterone in young healthy men (Leproult 2011).
- Maintain healthy body fat: Obesity suppresses testosterone (fat tissue converts T to estrogen via aromatase).
- Reduce stress: Chronic stress elevates cortisol, which suppresses testosterone production.
- Optimize micronutrients: Zinc (15-30 mg/day), magnesium (400 mg/day) and vitamin D are critical cofactors for testosterone synthesis.
Source: Effect of 1 week of sleep restriction on testosterone levels in young healthy men.
Address Underlying Causes of Low T
- Obesity: Lose weight through calorie deficit + resistance training. In men with obesity, testosterone tends to rise as fat is lost.
- Testicular dysfunction (primary hypogonadism): Varicocele repair, discontinue damaging medications (opioids, glucocorticoids).
- Pituitary dysfunction (secondary hypogonadism): Check LH, FSH, prolactin. May need MRI brain if pituitary tumor suspected.
- Medications: Opioids, glucocorticoids, statins (modest effect) can suppress T. Discuss alternatives with doctor.
For Women: Address PCOS or Adrenal Issues if T is High
- PCOS (most common cause in women): Metformin, inositol, low-carb diet, weight loss improve insulin sensitivity and reduce testosterone.
- Adrenal hyperplasia: May need glucocorticoid replacement if 17-hydroxyprogesterone elevated.
- Ovarian/adrenal tumors: Rare but require imaging if testosterone >150 ng/dL in women.
Supplement Support (Evidence is Moderate)
- Zinc (if deficient): 15-30 mg/day. Zinc deficiency suppresses testosterone.
- Vitamin D: Correct a deficiency. Vitamin D receptors are present in testes.
- Ashwagandha: 300-600 mg/day has raised testosterone in small trials in stressed men.
- Creatine: 5 g/day may modestly support T levels via improved training performance.
- Fenugreek, Tongkat Ali, Tribulus: Modest evidence; effects are small.
When to retest
- If low T confirmed: Retest along with LH, FSH, prolactin, estradiol to determine if primary vs secondary hypogonadism.
- If starting TRT: Retest total and free testosterone, hematocrit, PSA (men >40) after 6-8 weeks, then every 3-6 months.
- If optimizing lifestyle: Retest 3-6 months after weight loss, exercise program, sleep improvement.
- Routine screening: Consider checking testosterone in men >35 with fatigue, low libido, or difficulty building muscle. Women with similar symptoms may benefit from testing.
- Morning collection: Testosterone peaks in the morning (7-10 AM). Always test in the morning for accurate baseline.
Scientific Evidence
Testosterone Is Falling Across Generations
In the Massachusetts Male Aging Study (1,532 men aged 45-79, measured between 1987 and 2004), testosterone fell over calendar time independent of age. The drop was not explained by smoking, obesity, or other measured factors, and it was larger than the cross-sectional decline usually attributed to aging.
Source: A population-level decline in serum testosterone levels in American men.
Low Testosterone and Mortality
Among male veterans over 40, those with low testosterone (total below 250 ng/dL, or low free testosterone) had 34.9% mortality over up to 8 years, versus 20.1% in men with normal levels. After adjusting for age and illness the hazard ratio was 1.88. This is an observational association and does not show that raising testosterone lowers mortality.
Source: Low serum testosterone and mortality in male veterans.
Testosterone Replacement and Cardiovascular Safety
The TRAVERSE trial randomized 5,246 men aged 45-80 with symptoms of hypogonadism, two fasting testosterone levels below 300 ng/dL, and existing or high cardiovascular risk to testosterone gel (dosed to 350-750 ng/dL) or placebo. Major cardiac events occurred in 7.0% versus 7.3% (hazard ratio 0.96), meeting the noninferiority test. Atrial fibrillation, acute kidney injury, and pulmonary embolism were more common with testosterone.
Source: Cardiovascular Safety of Testosterone-Replacement Therapy.
Which Providers Test Total Testosterone?
Cheapest: Mito Health at $297/year. Most comprehensive: Function Health, 160+ biomarkers for $365/year.
17 panels that include it, cheapest first
| Provider | Annual Cost | Total Biomarkers | $/Biomarker |
|---|---|---|---|
| $297 | 100+ | $2.97 | |
 Superpower | $349 | 100+ | $3.49 |
| $349 | 75+ | $4.65 | |
 WHOOP Advanced Labs | $349 | 65 | $5.37 |
 Function Health | $365 | 160+ | $2.28 |
| $365 | 100+ | $3.65 | |
| $375 | 108 | $3.47 | |
| $449 | 83 | $5.41 | |
| $495 | 80+ | $6.19 | |
| $499 | 100+ | $4.99 | |
| $700 | 138 | $5.07 | |
| $829 | 54 | $15.35 | |
| $895 | 100+ | $8.95 | |
| $996 | 59 | $16.88 | |
| $1188 | 70+ | $16.97 | |
| $1198 | 40+ | $29.95 | |
| $1950 | 130+ | $15.00 |
$/Biomarker is annual cost divided by the panel's advertised biomarker count, not the price of this one test. We track 23 blood test providers (32 plans); 21 of those plans are itemized marker by marker. Compare all of them.
4 itemized panels do not include Total Testosterone
Labcorp OnDemand · Marek Health Base · Empirical Health · Oura Health Panels
11 providers not itemized in our matrix
We have not itemized these marker by marker (some sell tests one at a time), so this page cannot say whether they offer Total Testosterone. Check with them directly.
Life Extension Standard · Quest Health · Ultrahuman Blood Vision · Lifeforce · Hundred Health · Personalabs · Walk-In Lab · HealthLabs · WHOOP Specialized Panels · Marek Health Essential · Vitality Blueprint Upload
Experts discussing Total Testosterone
Podcast episodes where clinicians and researchers cover this marker in depth. Curated by hand; an episode is listed only when the marker is a substantial topic, not a passing mention.
- A Deep Dive Into How To Interpret The Results Of Your Blood Testing
- Cortisol Decoded: The Myths & Truths About A Hormone Crucial To Your Health
- 7 Signs Your Cortisol and Adrenals Are Broken
- Testosterone Replacement Therapy, Hormone Testing 101, and More
- Best Of Hormone Health
- Episode 171: July 2022 Bloodwork Review
Frequently Asked Questions
What is the optimal range for Total Testosterone?
Published positions differ: Therapy considered below ~300 ng/dL with symptoms; harmonized lower limit ~264 ng/dL for young men (Endocrine Society clinical practice guideline (2018)); 264-916 ng/dL (men 19-39) (Harmonized reference range (Travison et al. 2017, four US and European cohorts)); Below 213 ng/dL (7.4 nmol/L) carries higher all-cause mortality (Individual-participant meta-analysis (Yeap et al. 2024, Ann Intern Med)). Named practitioners target: men 700-1100 ng/dL (Quest) or 600-900 (LabCorp) / women 28-60 ng/dL (Life Extension). Lab reference interval: Men: 300-1000 ng/dL, Women: 15-70 ng/dL. That is what a lab report flags against, not an optimal target.
Which blood test providers include Total Testosterone?
17 of the 21 blood testing panels we itemize marker by marker include Total Testosterone in their panels. This biomarker is widely available across major providers.
Related: YouBoost rates lifestyle and supplement interventions by evidence; HRV Zone tracks recovery trends.
Medical Disclaimer
This information is for educational purposes only and is not medical advice. Always consult with a qualified healthcare provider about your specific health needs.
Last reviewed Sep 23, 2026 · First published Sep 30, 2025