Androgens and Hair Loss: How Hormones Drive Balding

What Is Androgenetic Alopecia?

Androgenetic alopecia is the medical term for the most common type of hair loss in both men and women. It's driven by androgens—hormones like testosterone and its byproduct DHT—and genetics. In men, it typically shows up as a receding hairline and thinning at the crown. In women, it's usually a diffuse thinning across the top and sides of the scalp while the frontal hairline stays intact. It's progressive, meaning it tends to worsen over time if left untreated. Despite the strong hormonal component, it's not a sign of poor health or abnormal hormone levels—it's simply how your hair follicles respond to normal androgens.

How Androgens Drive Hair Loss

The main culprit is dihydrotestosterone (DHT), a potent androgen converted from testosterone by the enzyme 5-alpha-reductase. In genetically susceptible hair follicles—particularly those at the temples, crown, and mid-scalp—DHT binds to androgen receptors and gradually miniaturizes the follicle. Over time, the hair shaft becomes thinner, shorter, and lighter until the follicle stops producing visible hair. This process is called follicular miniaturization. The key point: it's not that you have too much DHT overall, but that your follicles are sensitive to it.

• Testosterone is converted to DHT by 5-alpha-reductase type 2 in the hair follicle.
• DHT binds to androgen receptors in susceptible follicles, triggering miniaturization.
• Miniaturized hairs have a shorter growth phase (anagen) and longer resting phase (telogen).
• Over successive cycles, the follicle shrinks and may eventually stop producing hair.
• Follicles on the back and sides of the scalp are typically resistant to DHT—this is why they're used in hair transplants.

Causes and Risk Factors

Androgenetic alopecia is polygenic—meaning many genes contribute, not just one. Family history is the strongest risk factor. If your father or maternal grandfather had pattern hair loss, your risk is higher. Hormonal changes (like puberty, pregnancy, or menopause) can influence timing and severity, but the underlying sensitivity is genetic. Other factors like stress, diet, and certain medications can accelerate hair loss but aren't the root cause of androgenetic alopecia.

• Family history of pattern baldness (either side of the family).
• Age—risk increases with age, especially after 30 in men and after menopause in women.
• Ethnicity—prevalence and patterns vary across populations.
• Hormonal conditions like polycystic ovary syndrome (PCOS) in women can worsen androgen-related thinning.
• Certain medications (e.g., anabolic steroids) can accelerate androgen-driven loss.

Symptoms and Stages of Balding

Symptoms usually develop gradually. Men often notice a receding hairline first, then thinning at the crown. Women typically see widening of the part and diffuse thinning over the top of the scalp. The Norwood scale (for men) and Ludwig scale (for women) are common ways to stage hair loss. Early stages involve minimal visible thinning; moderate stages show clear recession or crown thinning; advanced stages involve large bald areas.

• Receding hairline at the temples (men).
• Thinning at the crown or vertex (men).
• Widening part and diffuse thinning on top (women).
• Increased shedding during washing or brushing.
• Miniaturized hairs—fine, short, lighter-colored strands.
• Scalp may become more visible under light.

How Androgenetic Alopecia Is Diagnosed

Diagnosis is usually clinical—based on history and visual inspection. A dermatologist or hair restoration specialist will ask about family history, hair loss pattern, and medical history. They may use a dermatoscope to look for miniaturized hairs and perform a pull test. Blood tests are sometimes ordered to rule out other causes like thyroid dysfunction, iron deficiency, or hormonal imbalances (especially in women). A biopsy is rarely needed but can confirm the diagnosis in unclear cases.

• Medical history and family history review.
• Visual assessment of hairline, crown, and part width.
• Dermoscopy (scalp magnification) to check for hair diameter diversity.
• Hair pull test to assess active shedding.
• Blood tests: ferritin, thyroid function, testosterone, DHEA-S (especially for women).
• Scalp biopsy in rare, ambiguous cases.

Treatment Options for Hormonal Hair Loss

Treatment aims to slow or stop progression and, in some cases, regrow hair. The two most proven medications are finasteride (oral, for men) and minoxidil (topical or oral). Finasteride blocks the conversion of testosterone to DHT, reducing follicular miniaturization. Minoxidil prolongs the growth phase and improves blood flow to the follicle. Other options include ketoconazole shampoo, low-level laser therapy, and platelet-rich plasma (PRP) injections. For women, spironolactone or oral minoxidil may be prescribed off-label. None of these are permanent cures—they work only as long as you use them.

• Finasteride (oral)—reduces DHT; prescription only; for men.
• Minoxidil (topical or oral)—stimulates growth; available OTC or by prescription.
• Ketoconazole shampoo—may have mild anti-androgen effect on scalp.
• Low-level laser therapy (LLLT)—may improve hair density; evidence is mixed.
• Platelet-rich plasma (PRP)—injections that may stimulate follicles; results vary.
• Spironolactone (for women)—anti-androgen; off-label for hair loss.

Is a Hair Transplant Suitable for You?

A hair transplant is a surgical option that moves DHT-resistant follicles from the back and sides of the scalp to thinning areas. It's not a cure for androgenetic alopecia—you'll still need medication to protect the transplanted and native hair. The best candidates have stable hair loss, good donor density, and realistic expectations. Age matters: younger patients may not have stabilized loss and could end up with unnatural hairlines if transplanted too early. A surgeon will assess donor supply, scalp laxity, and pattern progression.

• You have stable hair loss (not rapidly progressing).
• You have sufficient donor hair density at the back and sides.
• You're willing to use medication (finasteride/minoxidil) to maintain results.
• You have realistic expectations about density and coverage.
• You're in good general health and can tolerate surgery.
• You understand that multiple sessions may be needed for advanced loss.

Frequently Asked Questions