Know Your Blood Parameters: Testosterone
- Summarised by TGHC Editorial Team
- Aug 9, 2025
- 3 min read
Updated: Dec 4, 2025
Parameter Name
Testosterone
Testosterone is a steroid hormone belonging to the androgen group, which plays a crucial role in the development of male reproductive tissues as well as promoting secondary sexual characteristics such as increased muscle and bone mass. In both men and women, testosterone is produced in the testes and ovaries, respectively, and also in smaller amounts by the adrenal glands.
Test Type
Blood
The testosterone test is typically conducted using a blood sample drawn from a vein, usually from the arm. This method allows for accurate measurement of testosterone levels circulating in the bloodstream, which is essential for assessing hormonal health.
Normal Range
Men: 300 – 1,000 ng/dL
Women: 15 – 70 ng/dL
The normal testosterone levels can vary significantly between individuals and are influenced by factors such as age, time of day, and overall health. For men, testosterone levels are generally higher, peaking in early adulthood and gradually declining with age. In women, testosterone levels are much lower, but still play an important role in various bodily functions.
High Levels Indicate
Androgen-secreting tumors, steroid use, polycystic ovary syndrome (PCOS) in women.
Elevated testosterone levels in men can be indicative of conditions such as androgen-secreting tumors, which can arise from the testes or adrenal glands. In women, high levels may suggest polycystic ovary syndrome (PCOS), a hormonal disorder that can lead to irregular menstrual cycles and infertility. Additionally, the use of anabolic steroids for performance enhancement can also lead to increased testosterone levels.
Low Levels Indicate
Hypogonadism, pituitary disorders, aging, chronic illness.
Low testosterone levels can signal a variety of health issues. Hypogonadism, a condition in which the body doesn't produce enough testosterone, can result from problems with the testes or the pituitary gland. Other factors contributing to low testosterone include aging, as levels naturally decline with age, as well as chronic illnesses such as diabetes or obesity, which can also impact hormone production.
Why It's Tested
To evaluate sexual dysfunction, infertility, delayed or precocious puberty, and androgen excess.
The testosterone test is performed for several reasons. It is commonly used to investigate cases of sexual dysfunction, such as erectile dysfunction in men or reduced libido in women. It is also critical in assessing infertility issues, as hormonal imbalances can affect reproductive health. Additionally, the test may be utilized to evaluate delayed or precocious puberty in adolescents, as testosterone levels play a key role in sexual development.
Associated Symptoms (if abnormal)
High: Aggression, acne, hirsutism (in women), infertility.
Low: Fatigue, decreased libido, erectile dysfunction, muscle loss.
Abnormal testosterone levels can lead to a range of symptoms. High testosterone levels in men may result in increased aggression, mood swings, and physical changes such as acne or excessive hair growth (hirsutism) in women. On the other hand, low testosterone levels can manifest as fatigue, a significant decrease in sexual desire, erectile dysfunction, and even loss of muscle mass, which can impact overall physical health and quality of life.
What To Do If Abnormal
Confirm with repeat test in morning, evaluate LH/FSH; endocrine referral may be necessary.
If testosterone levels are found to be abnormal, it is important to confirm these results with a repeat test, ideally conducted in the morning when testosterone levels are typically at their peak. Further evaluation may include measuring other hormones such as luteinizing hormone (LH) and follicle-stimulating hormone (FSH) to assess the function of the pituitary gland. If necessary, a referral to an endocrinologist may be warranted for specialized care and management.
Common Conditions Related
Hypogonadism, androgen-secreting tumors, PCOS, adrenal disorders.
Several medical conditions are closely associated with abnormal testosterone levels. Hypogonadism is a primary condition characterized by insufficient testosterone production, which can have various underlying causes. Androgen-secreting tumors, whether originating from the adrenal glands or reproductive organs, can lead to excessive production of testosterone. In women, conditions like PCOS not only cause hormonal imbalances but can also lead to metabolic issues. Adrenal disorders can also affect hormone levels, contributing to abnormal testosterone readings.
Nutrition or Lifestyle Connection
Maintain healthy weight, manage stress, balanced diet with zinc and vitamin D.
Nutrition and lifestyle choices play a significant role in maintaining healthy testosterone levels. Achieving and maintaining a healthy weight is crucial, as obesity is linked to lower testosterone levels. Managing stress through relaxation techniques, exercise, and adequate sleep can also positively impact hormone regulation. A balanced diet rich in nutrients, particularly zinc and vitamin D, is essential, as these nutrients are vital for testosterone production and overall hormonal health.
References (APA Format)
Melmed, S. et al. (2016). Williams Textbook of Endocrinology (13th ed.). Elsevier.
MedlinePlus. (2023). Testosterone Test. https://medlineplus.gov/lab-tests/testosterone/
