# Total Testosterone

> Testosterone is a vital male sex hormone, also present in women in smaller amounts, crucial for various bodily functions. In men, testosterone plays a key 

*Source: [https://www.health3.app/biomarkers/totaltesto](https://www.health3.app/biomarkers/totaltesto)*

### On This Page

- What it measures
- Measurement units
- Reference ranges
- Health impact
- Related biomarkers
- Scientific references

## What is Total Testosterone?

Testosterone is a vital male sex hormone, also present in women in smaller amounts, crucial for various bodily functions. In men, testosterone plays a key role in the development of male reproductive tissues, including the testes and prostate, and promotes secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. It also influences libido, mood, and energy levels. In women, testosterone contributes to ovarian function, bone strength, and sexual desire.

Total testosterone represents the sum of both free testosterone and testosterone bound to proteins in the blood, such as sex hormone-binding globulin (SHBG) and albumin. Measuring total testosterone levels provides an overall assessment of the body's testosterone production.

**Low testosterone levels in men**, known as hypogonadism, can lead to a range of symptoms and health issues. These can include reduced libido, erectile dysfunction, decreased muscle mass and strength, increased body fat, decreased bone density (osteoporosis), low energy levels, fatigue, depression, and impaired cognitive function. Causes of low testosterone include aging, obesity, certain chronic diseases, and specific medical treatments. **In women, low testosterone levels can result in diminished libido, fatigue, and a decrease in well-being**.

Conversely, excessively **high testosterone levels** can cause problems as well. In men, it might be due to anabolic steroid use or testosterone supplementation, leading to aggressive behavior, acne, increased risk of heart disease, liver disease, and decreased sperm production. In women, high testosterone levels can indicate conditions like polycystic ovary syndrome (PCOS), manifesting in symptoms such as irregular menstrual cycles, excess hair growth, and obesity. Balancing testosterone levels through lifestyle changes, medication, or treating the underlying cause is crucial for overall health and well-being.

To **maintain healthy testosterone levels**:

- Engage in regular exercise, particularly resistance training, as it can help boost testosterone levels naturally.
- Maintain a healthy weight, as obesity can contribute to lower testosterone levels.
- Ensure a balanced diet rich in protein, healthy fats, and complex carbohydrates, as these nutrients are essential for hormone production and overall health.

## Measurement Units

Total Testosterone can be measured in: ng/100mL, ng/dL, ng/L, ng%, nmol/L, µg/L

## Reference Ranges by Age and Gender

Reference ranges represent typical values for healthy individuals. Your healthcare provider must interpret your specific results.

| Age Range | Gender | Unit | Optimal | Normal | Source |
| --- | --- | --- | --- | --- | --- |
| All ages | Woman | ng/dL | - | 7.1 - 49.8 | Botelho, 2011 |
| All ages | Man | ng/dL | - | 264 - 916 | Bhasin, 2017 |

## Related Biomarkers

- [**Free Serum Cortisol**](https://www.health3.app/biomarkers/cortisol_free_serum)

 High cortisol is under certain conditions associated with lowers levels of testosterone. [Brownlee, 2005][Cumming, 1983].
- **Estradiol** (Coming Soon)

 In men, testosterone is the primary precursor for estradiol production via the action of the enzyme aromatase. The balance between testosterone and estradiol is crucial for maintaining various physiological functions, including reproductive health, bone density, and cardiovascular health. Elevated estradiol levels in men can lead to symptoms such as gynecomastia (breast tissue growth), while low levels can affect bone health and libido.[Schulster, 2016]
- [**Free Testosterone**](https://www.health3.app/biomarkers/freetestos)

 Total testosterone represents the sum of both free testosterone and testosterone bound to proteins in the blood, such as sex hormone-binding globulin (SHBG) and albumin. Measuring total testosterone levels provides an overall assessment of the body's testosterone production. Measuring free testosterone levels can provide a more accurate assessment of the hormone's activity in the body, as it represents the readily available portion of testosterone.
- [**DHEAS**](https://www.health3.app/biomarkers/dheas)

 DHEAS serves as a key testosterone precursor in both sexes. In men, it contributes to total androgenic activity, becoming more important as testicular production naturally declines with age. In women, DHEAS conversion significantly contributes to testosterone levels, particularly post-menopause. In men, this contribution is smaller, but relevant especially in the elderly.[Labrie, 2001]
- [**Follicle-stimulating hormone (FSH)**](https://www.health3.app/biomarkers/fsh)

 In men, FSH acts on Sertoli cells to support sperm development, while LH-driven testosterone completes maturation. Proper sperm production requires both hormones working in concert.[Iliadou, 2015]

## Academic References

1. Liu L. The association between the levels of serum ferritin and sex hormones in a large scale of Chinese male population (2013). *PLoS One*. [View Source](https://doi.org/10.1371/journal.pone.0075908)
2. Bhasin S, Fiers T, Kaufman JM, Lapauw B, Matsumoto AM, Orwoll E, Travison TG, Vesper HW, Wang Y, and Wu F. Harmonized Reference Ranges for Circulating Testosterone Levels in Men of Four Cohort Studies in the United States and Europe (2017). *J Clin Endocrinol Metab*. [DOI: 10.1210/jc.2016-2935](https://doi.org/10.1210/jc.2016-2935)
3. Botelho JC, Caudill SP, Vesper HW, Vidal M, and Wang Y. Serum Total Testosterone Concentrations in the US Household Population from the NHANES 2011–2012 Study Population (2011). *Clin Chem*. [DOI: 10.1373/clinchem.2015.245969](https://doi.org/10.1373/clinchem.2015.245969)
4. Labrie F. DHEA and its transformation into androgens and estrogens in peripheral target tissues: intracrinology. (2001). *Front Neuroendocrinol*.
5. Brownlee KK, Hackney AC, and Moore AW. Relationship between circulating cortisol and testosterone: influence of physical exercise (2005). *J Sports Sci Med*. [View Source](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3880087/)
6. Iliadou PK. The Sertoli cell: novel clinical potentiality. (2015). *Hormones*. [View Source](https://doi.org/10.14310/horm.2002.1648)
7. Jungner I. and Walldius G.. Apolipoprotein B and apolipoprotein A-I: risk indicators of coronary heart disease and targets for lipid-modifying therapy (2004). *Journal of Internal Medicine*. [DOI: 10.1046/j.1365-2796.2003.01276.x](https://doi.org/10.1046/j.1365-2796.2003.01276.x)
8. Bhasin S, Lee MI, Roth SM, and Sinha-Hikim I. Testosterone-induced muscle hypertrophy is associated with an increase in satellite cell number in healthy young men (2003). *Am J Physiol Endocrinol Metab*. [DOI: 10.1152/ajpendo.00370.2002](https://doi.org/10.1152/ajpendo.00370.2002)
9. Wittert G. The relationship between sleep disorders and testosterone in men (2014). *Asian J Androl*. [DOI: 10.4103/1008-682X.122586](https://doi.org/10.4103/1008-682X.122586)
10. Barrett-Connor E., Cauley J. A., Ensrud K. E., Ewing S. K., Fink H. A., Orwoll S., and Taylor B. C.. Association of testosterone and estradiol deficiency with osteoporosis and rapid bone loss in older men (2006). *The Journal of Clinical Endocrinology & Metabolism*. [DOI: 10.1210/jc.2006-0173](https://doi.org/10.1210/jc.2006-0173)
11. Cumming DC, Quigley ME, and Yen SS. Acute suppression of circulating testosterone levels by cortisol in men (1983). *J Clin Endocrinol Metab*. [DOI: 10.1210/jcem-57-3-671](https://doi.org/10.1210/jcem-57-3-671)
12. Chin K. Y., Mohamad N. V., and Soelaiman I. N.. A concise review of testosterone and bone health (2016). *Clinical Interventions in Aging*. [DOI: 10.2147/CIA.S115472](https://doi.org/10.2147/CIA.S115472)
13. Bhasin S and Herbst KL. Testosterone action on skeletal muscle (2004). *Curr Opin Clin Nutr Metab Care*. [DOI: 10.1097/00075197-200405000-00006](https://doi.org/10.1097/00075197-200405000-00006)
14. Leproult R and Van Cauter E. Effect of 1 week of sleep restriction on testosterone levels in young healthy men (2011). *JAMA*. [DOI: 10.1001/jama.2011.710](https://doi.org/10.1001/jama.2011.710)
15. Chin K. Y. and Ima-Nirwana S.. Sex steroids and bone health status in men (2012). *International Journal of Endocrinology*. [DOI: 10.1155/2012/208719](https://doi.org/10.1155/2012/208719)

### ⚠️ Important Medical Information

This reference page is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Reference ranges vary between laboratories. Always review your lab results with a qualified healthcare provider.