Hair Health . Symptoms guide
Thinning at the Crown: Hormonal and Nutritional Causes
Quick answer
Visible scalp at the crown is the most common pattern of androgenetic alopecia. In men it usually means DHT-driven miniaturisation. In women a similar pattern can be androgenetic (female pattern hair loss) but is more often combined with iron deficiency, thyroid imbalance or perimenopausal hormonal change. Targeted bloodwork separates these so the treatment plan matches the cause.
This patient information is being clinically reviewed by our team. The factual content draws on UK guidance (NHS, NICE, British Association of Dermatologists, and other specialist society guidance where cited).
What this might be
- Androgenetic alopecia. In men: classic crown thinning. In women: diffuse widening of the central parting, sometimes with a Christmas-tree pattern that breaches the front hair line.
- Iron deficiency. Low ferritin can slow follicle cycling well before haemoglobin falls into the anaemic range; many trichologists prefer to see ferritin comfortably within range for women with active shedding rather than at the bottom end.
- Thyroid dysfunction. TSH outside reference range can cause diffuse thinning across the scalp; areas that are already genetically susceptible, including the crown, can look thinner sooner.
- Perimenopausal hormonal shift. Falling oestrogen unmasks androgen effects, accelerating thinning in genetically susceptible women.
Common features that suggest this
- Wider part line than 12 months ago
- Visible scalp at the crown under bright light
- Reduced ponytail thickness
- Slower hair regrowth at trim points
Recommended tests
Same-day appointments at our Harley Street clinic, results clinician-reviewed.
Need a marker not in these panels? Build a custom panel and a GMC-registered clinician will design one for you.
Markers your clinician will commonly look at
These are the individual blood markers in the recommended panels above. Click any to read what it measures, its UK reference range, and what high or low values mean.
Testing advice
Book a morning slot for accurate hormone reading. For women, days 2 to 5 of the cycle give the most interpretable oestrogen and androgen baseline.
Common questions
Is crown thinning the same in men and women?
The underlying biology is similar (androgen-driven miniaturisation) but women rarely lose hair as completely. Female-pattern thinning preserves the front hair line. Combined hormone testing is more useful in women because oestrogen, thyroid and androgens interact.
What if my DHT is normal but I am still thinning?
Scalp sensitivity to DHT matters more than absolute blood levels. Treatment decisions weigh history, examination and bloodwork together, not bloodwork alone.