Testosterone in Women: Why It Matters More Than You Think

When most people hear "testosterone," they think of men. But testosterone is actually the most abundant active sex hormone in women too - produced in greater quantities than estrogen throughout most of a woman's life. And when levels decline or become imbalanced, the effects can be just as profound.

Testosterone's Role in Women: Far Beyond Reproduction

Testosterone in women is produced by the ovaries, the adrenal glands, and through peripheral conversion of other androgens. While women produce roughly one-tenth the amount men do, this smaller quantity plays an outsized role in health:

• Energy and vitality: Testosterone supports mitochondrial function and overall energy production
• Muscle mass and strength: Adequate levels help maintain lean body mass and metabolic rate
• Bone density: Testosterone works alongside estrogen to protect against osteoporosis
• Cognitive function: Testosterone receptors are found throughout the brain, and adequate levels support memory, focus, and processing speed
• Libido and sexual function: Testosterone is the primary driver of sexual desire in women
• Mood regulation: Low testosterone is associated with depression, apathy, and decreased motivation
• Cardiovascular health: Emerging research suggests testosterone has protective effects on blood vessel function

Why Testosterone Gets Overlooked in Women

Despite its importance, testosterone is rarely tested in women unless they present with overt signs of excess (like facial hair or severe acne). This creates a major blind spot: low testosterone in women is almost never diagnosed, even when symptoms are staring clinicians in the face.

The reasons for this gap include:

• No FDA-approved testosterone therapy for women in the United States, which reduces clinical attention
• Outdated belief that testosterone is irrelevant to women's health
• Poorly defined reference ranges that vary wildly between labs
• SHBG confounding: Total testosterone can appear normal while free (active) testosterone is critically low

Symptoms of Low Testosterone in Women

Low testosterone in women can produce a constellation of symptoms that are often attributed to depression, aging, or "just stress":

• Persistent fatigue that does not improve with sleep
• Low or absent libido - the most classic symptom
• Difficulty building or maintaining muscle despite regular exercise
• Unexplained weight gain, particularly increased body fat relative to muscle
• Brain fog and difficulty concentrating
• Depressed mood, apathy, or loss of motivation
• Decreased sense of well-being
• Joint pain or muscle weakness
• Thinning hair (though excess testosterone causes the opposite - this reflects a complex balance)

Free Testosterone vs Total Testosterone: Why It Matters

This distinction is critical and frequently misunderstood. Total testosterone measures all testosterone in your blood, but a large portion is bound to proteins - primarily sex hormone binding globulin (SHBG) and albumin. Only the unbound fraction, called free testosterone, is biologically active and available for your cells to use.

A woman can have a "normal" total testosterone level while her free testosterone is extremely low if her SHBG is elevated. This is particularly common in women taking oral contraceptives, which dramatically increase SHBG.

The SHBG Connection

SHBG is a protein produced by the liver that binds to sex hormones and reduces their bioavailability. Factors that increase SHBG include:

• Oral contraceptives (the most common cause in premenopausal women)
• Hyperthyroidism
• Liver disease
• Low caloric intake or eating disorders
• Aging

Factors that decrease SHBG include:

• Insulin resistance and PCOS
• Hypothyroidism
• Obesity
• High-dose corticosteroids

Testing both total testosterone, free testosterone, and SHBG together provides the complete picture. Testing total testosterone alone is often misleading.

Age-Related Testosterone Decline

Women's testosterone levels peak in the early 20s and decline steadily throughout life. By age 40, a woman's testosterone level is approximately half of what it was at age 20. By menopause, levels may be 75% lower than their peak.

This decline happens gradually:

• 20s: Peak testosterone production; highest energy, libido, and muscle recovery
• 30s: Levels begin a steady decline of approximately 1-2% per year; subtle changes in energy and body composition may appear
• 40s: Noticeable decline accelerates; many women experience the first significant symptoms of low testosterone alongside perimenopause
• 50s and beyond: Post-menopause, ovarian testosterone production drops significantly; adrenal contribution becomes the primary source

Unlike menopause - which involves a dramatic drop in estrogen and progesterone - testosterone decline is gradual, making it easier to dismiss symptoms as "normal aging."

Optimal Ranges for Women

Standard lab reference ranges for testosterone in women are notoriously broad. A "normal" range might span from 8 to 60 ng/dL for total testosterone, which is not clinically useful. Many functional and integrative medicine practitioners use tighter optimal ranges:

• Total testosterone: 30-50 ng/dL (some practitioners aim higher depending on symptoms)
• Free testosterone: 3-8 pg/mL
• SHBG: 40-120 nmol/L (context-dependent)

These numbers should always be interpreted alongside symptoms. A woman with a total testosterone of 20 ng/dL who feels well is different from one at the same level experiencing fatigue, low libido, and cognitive decline.

Lab Tests That Can Help

The EllaDx Hormone & Longevity Panel includes the key biomarkers for a thorough testosterone assessment:

• Total testosterone - overall production
• Free testosterone - the biologically active fraction
• SHBG - to understand binding and bioavailability
• DHEA-S - the primary adrenal androgen precursor to testosterone
• Estradiol - testosterone-to-estrogen ratio matters for symptom assessment
• LH and FSH - to evaluate pituitary signaling to the ovaries
• Cortisol - chronic stress can suppress androgen production
• Thyroid panel - thyroid status directly affects SHBG and testosterone metabolism
• Fasting insulin - insulin resistance lowers SHBG and can artificially raise total testosterone

Supporting Healthy Testosterone Levels

While testosterone replacement therapy for women is an active area of research, there are foundational strategies that support healthy androgen levels:

• Resistance training: Strength training is one of the most effective natural ways to support testosterone production and sensitivity
• Adequate protein intake: Amino acids are essential for hormone synthesis
• Quality sleep: Testosterone production is linked to sleep quality and duration
• Stress management: Chronic cortisol elevation suppresses androgen production
• Healthy body composition: Both excess body fat and extremely low body fat can impair testosterone production
• Review medications: Oral contraceptives, certain antidepressants, and corticosteroids can all suppress testosterone or raise SHBG

References

• Davis, S. R., & Wahlin-Jacobsen, S. (2015). Testosterone in women - the clinical significance. *The Lancet Diabetes & Endocrinology*, 3(12), 980-992.
• Zumoff, B., et al. (1995). Twenty-four-hour mean plasma testosterone concentration declines with age in normal premenopausal women. *Journal of Clinical Endocrinology & Metabolism*, 80(4), 1429-1430.
• Wierman, M. E., et al. (2014). Androgen therapy in women: a reappraisal. *Journal of Clinical Endocrinology & Metabolism*, 99(10), 3489-3510.
• Panzer, C., et al. (2006). Impact of oral contraceptives on sex hormone-binding globulin and androgen levels. *Journal of Sexual Medicine*, 3(1), 104-113.
• Glaser, R., & Dimitrakakis, C. (2013). Testosterone therapy in women: myths and misconceptions. *Maturitas*, 74(3), 230-234.
• Davison, S. L., et al. (2005). Androgen levels in adult females: changes with age, menopause, and oophorectomy. *Journal of Clinical Endocrinology & Metabolism*, 90(7), 3847-3853.