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# Testosterone

tes·tos·ter·one - tes-TOS-tuh-rone

## Definition

Testosterone is the primary male sex [hormone](/glossary/hormone) (androgen), though it is produced in smaller amounts in women as well and plays important roles in both sexes. In men, testosterone is produced primarily by the testes and is responsible for the development of male reproductive tissues, the deepening of the voice during puberty, growth of facial and body hair, increased muscle mass and bone density, and the maintenance of sex drive (libido) and sperm production throughout life.

In women, testosterone is produced by the ovaries and adrenal glands in much smaller quantities but is nonetheless essential for bone strength, muscle mass, libido, cognitive function, and overall energy levels. Excess testosterone in women - as seen in [PCOS](/glossary/pcos) - can cause [acne](/glossary/acne-vulgaris), unwanted hair growth, and menstrual irregularities.

Testosterone levels in men decline gradually with age - approximately 1-2% per year after age 30. This gradual decline is normal, but some men experience a more significant drop that causes symptoms including fatigue, reduced libido, erectile dysfunction, decreased muscle mass, increased body fat, mood changes, and reduced bone density. When symptoms are present and testosterone levels are confirmed to be below the normal range, the condition is called hypogonadism or "low T."

## Key Facts

-   • Normal testosterone levels in adult men are typically 300-1,000 ng/dL; in women, 15-70 ng/dL. 
-   • Testosterone levels naturally decline about 1-2% per year after age 30 in men. 
-   • Sleep, exercise, and nutrition significantly influence testosterone production - poor sleep alone can reduce testosterone by 10-15%. 
-   • Testosterone replacement therapy (TRT) is effective for confirmed hypogonadism but carries risks including cardiovascular effects and fertility impairment. 
-   • Resistance training and high-intensity exercise naturally boost testosterone levels in both men and women. 
-   • Obesity is strongly associated with lower testosterone in men - weight loss can significantly increase levels. 

## How It Relates To Your Health

If you're experiencing symptoms of low testosterone - fatigue, reduced libido, mood changes, loss of muscle mass - blood testing can determine whether your testosterone levels are genuinely low. It's important to have levels tested properly (morning blood draw, as levels are highest in the morning) and to rule out other causes of symptoms before pursuing treatment.

Natural strategies for supporting healthy testosterone levels include regular resistance training, adequate sleep (7-9 hours), maintaining a healthy body weight, managing stress, and ensuring sufficient intake of zinc, vitamin D, and magnesium - all of which are involved in testosterone production.

## Related Terms

[PCOS](/glossary/pcos)[Cortisol](/glossary/cortisol)[Osteoporosis](/glossary/osteoporosis)[Insulin Resistance](/glossary/insulin-resistance)

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### Sleep Hygiene: 12 Evidence-Based Tips

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## Sources

1.  [Testosterone](https://my.clevelandclinic.org/health/articles/24100-testosterone) - Cleveland Clinic
2.  [Testosterone therapy: Potential benefits and risks](https://www.mayoclinic.org/healthy-lifestyle/sexual-health/in-depth/testosterone-therapy/art-20045728) - Mayo Clinic

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[Definition](#definition)[Key Facts](#key-facts)[How It Relates To Your Health](#health-relevance)[Related Terms](#related-terms)[Related Articles](#related-articles)[Sources](#sources)

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