Testosterone, Total

Total testosterone measures the sum of all testosterone circulating in the bloodstream, including:

• Free testosterone (unbound and active)

• Protein-bound testosterone attached to sex hormone-binding globulin (SHBG) and albumin
  

Produced primarily by the Leydig cells in the testes under stimulation by luteinizing hormone (LH), testosterone is the primary androgen hormone responsible for masculine traits, reproductive function, muscle development, bone density, and red blood cell production.

While only a small fraction of testosterone is free and biologically active, total testosterone provides an overall snapshot of hormone production capacity and is a key first step in assessing androgen balance and male endocrine health.

Total testosterone reflects much more than reproductive health — it’s also a window into metabolic, cardiovascular, and cognitive vitality.

• Low total testosterone is associated with fatigue, depressed mood, decreased libido, loss of muscle and bone mass, and metabolic dysfunction (including insulin resistance and obesity). Chronically low levels, known as hypogonadism, can also increase risk of osteoporosis, cardiovascular disease, and type 2 diabetes.
  

• High total testosterone may occur from anabolic steroid use, testicular or adrenal tumors, or overactive pituitary stimulation, and can lead to acne, hair loss, infertility, or elevated red blood cell counts.
  

Understanding total testosterone helps uncover underlying hormonal or systemic issues that can impact long-term male health and vitality.

Testosterone production is influenced by nutrition, lifestyle, stress, sleep, and environmental factors that affect the hypothalamic–pituitary–gonadal (HPG) axis and SHBG levels.

Dietary Factors:

• Supports healthy testosterone: Adequate zinc (oysters, beef, pumpkin seeds), vitamin D (fatty fish, eggs, fortified foods), and healthy fats (olive oil, avocado, nuts).

• Lowers testosterone: Excessive alcohol, refined sugar, and trans fats impair testicular function and insulin sensitivity.
  

Lifestyle Factors:

• Boosts levels: Resistance and strength training, regular sleep, maintaining a healthy weight.

• Reduces levels: Chronic stress (via high cortisol), sleep deprivation, inactivity, or obesity.
  

Related Biomarkers:

• Luteinizing hormone (LH): Stimulates testosterone production; low LH may indicate pituitary dysfunction.

• Sex hormone-binding globulin (SHBG): Binds testosterone; high SHBG reduces free testosterone.
  

Micronutrient Impacts:

• Deficiency in magnesium, vitamin D, and zinc can impair testosterone synthesis and receptor sensitivity.
  

Environmental Influences:

• Endocrine-disrupting chemicals (EDCs) such as bisphenol A (BPA), phthalates, and pesticides interfere with androgen receptor signaling and testicular function.

If Total Testosterone is High

High total testosterone is uncommon without external factors and may reflect anabolic steroid use or hormone-secreting tumors.

Diet

• Reduce red meat and high-fat dairy intake if excessive.

• Emphasise anti-inflammatory foods: vegetables, whole grains, berries, and cruciferous vegetables (broccoli, kale, cauliflower) to support liver detoxification.

• Avoid alcohol and refined sugars, which can increase aromatization of testosterone to estrogen.
  

Lifestyle

• Practice moderate-intensity exercise and avoid overtraining, which may increase stress hormones.

• Prioritise stress reduction (yoga, meditation, breath-work).

• Avoid or discontinue testosterone-boosting supplements or anabolic substances unless prescribed.
  

Supplements

• Do not take additional testosterone or boosters without medical supervision.

• Support liver function with omega-3 fatty acids (1–2 g/day) and cruciferous vegetables for hormone metabolism.
  

Additional Considerations

• Consider evaluation for adrenal or testicular hyperactivity, tumour presence, or steroid exposure.

• Test related markers: DHEA-S, SHBG, LH, and haematocrit to identify cause.
  

If Total Testosterone is Low

Low testosterone may result from nutrient deficiencies, pituitary dysfunction, or metabolic stress.

Diet

• Include zinc-rich foods (oysters, grass-fed beef, pumpkin seeds).

• Eat vitamin D–rich foods (salmon, eggs, sardines, fortified dairy).

• Incorporate healthy fats (avocado, olive oil, nuts) to support hormone synthesis.

• Limit refined sugars and processed foods, which contribute to insulin resistance and lower testosterone production.
  

Lifestyle

• Engage in resistance training 3–4 times per week to stimulate natural testosterone production.

• Achieve and maintain a healthy body weight — visceral fat reduces testosterone by converting it to oestrogen.

• Get 7–9 hours of quality sleep per night; most testosterone is released during deep sleep cycles.

• Manage chronic stress through restorative activities and breathing exercises.
  

Supplements

• Zinc (15–30 mg/day): Essential for testosterone biosynthesis.

• Vitamin D3 (2,000–4,000 IU/day): Enhances androgen receptor function.

• Magnesium (200–400 mg/day): Supports energy metabolism and hormone balance.
  

Additional Considerations

• Investigate possible hypogonadism, pituitary disorders, or chronic illness.

• Testing LH, FSH, SHBG, and free testosterone can clarify whether the issue lies in hormone production or transport.

• Medical consultation and supervision is required before considering hormone therapy.

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2. Bhasin, S., Brito, J. P., Cunningham, G. R., et al. (2018). Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology & Metabolism, 103(5), 1715–1744. https://doi.org/10.1210/jc.2018-00229
   

3. Kelly, D. M., & Jones, T. H. (2015). Testosterone: A Metabolic Hormone in Health and Disease. Journal of Endocrinology, 217(3), R25–R45.
   

4. Travison, T. G., Vesper, H. W., Orwoll, E., et al. (2017). Harmonized Reference Ranges for Circulating Testosterone Levels in Men of Four Cohort Studies in the United States and Europe. Journal of Clinical Endocrinology & Metabolism, 102(4), 1161–1173.
   

5. Grossmann, M. (2018). Low Testosterone in Men With Type 2 Diabetes: Significance and Treatment.Journal of Clinical Endocrinology & Metabolism, 103(8), 2865–2874.