Why Hormones Matter in the Hair-Growth Cycle
Human scalp hair follows a repeating timetable with four key phases. Estrogens, thyroid hormones, and androgens all influence how long each stage lasts. Elevated androgen activity—especially from DHT—or heightened follicle sensitivity can shorten anagen, lengthen telogen, and push more follicles into dormancy at once. The visible result is gradual thinning typical of androgenetic alopecia. As PMC states, the four phases are:- Anagen (growth): Lasts two to six years and determines final length.
- Catagen (transition): A brief one- to two-week window when the follicle detaches from its blood supply and starts to regress.
- Telogen (rest): Roughly three months; the old shaft is released so new anagen growth can begin.
- Exogen (shedding): Lasts roughly two to five months; the fully formed hair shaft detaches and is released—shedding about 50-100 hairs a day is considered normal—while a new anagen fiber develops underneath
DHT: A Highly Active Form of Testosterone
About five-to-ten percent of circulating testosterone is converted into DHT by the enzyme 5-alpha-reductase (5-AR), found in skin, liver, prostate, and hair follicles. Although only a small fraction of testosterone undergoes this change, the resulting hormone is far more assertive: DHT binds androgen receptors with roughly double the affinity and remains attached about five times longer than testosterone. DHT production increases during puberty, remains steady through mid-adulthood, and can rise again in specific hormonal states (for example, polycystic ovary syndrome in women or anabolic-steroid use in athletes). Genetic differences in 5-AR activity also influence how much DHT individuals generate.How DHT Leads to Miniaturization and Balding
- Receptor Binding: DHT enters the dermal papilla and attaches to androgen receptors in the follicle bulb.
- Gene Expression Shift: Binding alters local signaling proteins, reducing genes that keep follicles large and active while increasing factors that slow growth.
- Shorter Anagen, Longer Telogen: Each growth cycle becomes progressively briefer, yielding thinner, lighter-colored hairs.
- Vascular and Matrix Changes: DHT reduces local blood flow and cell-matrix size, depriving the follicle of nutrients until it can no longer produce visible hair.
Who Is Most at Risk?
- Genetic predisposition: Variations in the androgen-receptor (AR) gene, such as the StuI polymorphism, heighten follicle sensitivity to DHT.
- Age & life stage: Incidence rises after the mid-twenties in men and accelerates post-menopause in women when protective estrogen levels fall.
- Lifestyle factors: Chronic stress, high-glycemic diets, rapid weight changes, and exogenous anabolic steroids can raise free testosterone or 5-AR activity.
Effective Ways to Lower DHT & Save Hair
Even though genetics set the stage for androgenetic alopecia, a range of therapies can lower circulating DHT, block its binding sites, or jump-start follicles that have already begun to miniaturize. Let’s examine the approaches with the strongest clinical support.1. Prescription 5-α Reductase (5-AR) Inhibitors
- Finasteride (1 mg daily) — Selectively blocks type II 5-AR and, in large randomized trials, halted loss and improved density in about two-thirds of men after two years.
- Dutasteride (0.5 mg daily) — Inhibits both type I and II isoenzymes, suppressing scalp DHT more completely and outperforming finasteride in direct comparisons while showing a similar side-effect profile.
2. Topical & Adjunct Therapies
- Minoxidil 5 % (foam/solution) — Extends the anagen phase by increasing scalp blood flow; works independently of hormone pathways and pairs well with 5-AR inhibitors.
- Topical finasteride or dutasteride — Early studies suggest meaningful DHT reduction with lower systemic exposure; long-term data are still emerging.
3. In-Office Medical Procedures
- Platelet-Rich Plasma (PRP/PRF) — Concentrated growth factors injected into the scalp have improved hair density and shaft thickness in randomized controlled trials.
- Low-Level Laser Therapy (LLLT) — FDA-cleared red-light devices increase cellular energy (ATP) and, in meta-analysis, significantly boost hair counts versus sham treatment.
- Microneedling + topical growth serums — Creates micro-channels that enhance absorption of minoxidil or peptide complexes and stimulates collagen around follicles.
- Hair Transplantation (FUE/FUT) — Relocates DHT-resistant follicles from the occipital scalp when medical therapy cannot recover adequate density.
4. Nutritional & Botanical DHT Blockers
- Saw Palmetto (Serenoa repens, 320 mg extract) — Multiple randomized trials report decreased shedding and modest caliber gains, likely via partial 5-AR inhibition.
- Pumpkin-Seed Oil (400 mg daily) — A placebo-controlled study showed a 40 % average increase in hair count after 24 weeks, attributed to mild 5-AR blockade and anti-inflammatory effects.
Lifestyle Strategies That Support Treatment
- Anti-inflammatory nutrition: Emphasize omega-3-rich fish, berries, and green tea.
- Regular exercise: Improves insulin sensitivity and helps stabilize androgen levels.
- Stress management: Lower cortisol through mindfulness, yoga, or other relaxation techniques.
- Scalp hygiene: Gentle cleansing and massage keep follicles clear and improve circulation.
Next Steps
DHT-related hair loss is common but manageable. A treatment plan combining prescription medication, evidence-based in-office procedures, and supportive lifestyle habits can preserve existing strands and restore density. Hair Restoration Seattle provides individualized care rooted in current research and years of surgical experience. Call (206)-209-0988 to book a consultation and discuss the most effective strategy for your stage of hair loss.