Symptom

Hair Loss

Diffuse hair shedding often points at iron deficiency, thyroid dysfunction or recent illness rather than primary skin disease. The lab work-up is short and high-yield.

What it means

Hair loss can be patchy (alopecia areata, fungal infection), patterned (androgenetic alopecia) or diffuse (telogen effluvium, nutritional deficiency, thyroid disease). Diffuse shedding noticed on the pillow, in the shower drain or while brushing typically reflects a systemic trigger rather than scalp disease. Common reversible drivers are iron deficiency, thyroid dysfunction, vitamin D deficiency, B12 deficiency, and recent illness or major stress (telogen effluvium peaks 3 months after the trigger).

Common causes

  • Iron deficiency — even with normal haemoglobin; ferritin <30 ng/mL is the marker.
  • Thyroid dysfunction — both hyperthyroidism and hypothyroidism can cause diffuse shedding.
  • Vitamin D and B12 deficiency — increasingly recognised contributors.
  • Telogen effluvium — diffuse shedding 3 months after major illness, surgery, childbirth or weight loss.
  • Androgenetic alopecia — pattern hair loss, genetic, gradual.
  • Polycystic ovary syndrome — diffuse thinning plus features of androgen excess.

Lab work-up approach

Mediora interprets the focused nutritional and thyroid panel: ferritin, TSH, vitamin D, B12, sometimes CBC. Skin examination for patterned vs patchy loss is the clinician's job.

Tests Mediora.AI can interpret

Related conditions

When to see a doctor

Diffuse hair loss lasting more than 3 months, sudden patchy hair loss, or hair loss with scalp inflammation warrants a primary-care or dermatology visit. Most nutritional and thyroid causes are reversible — early identification matters.

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