Overview
Hair loss (alopecia) refers to abnormal shedding or thinning of hair from the scalp or other body areas. Normal hair shedding is 50-100 hairs per day; beyond this may indicate pathological hair loss. This HealthKit category type allows users to track hair loss episodes, helping identify patterns related to hormonal changes, nutritional deficiencies, or underlying conditions.
Health Significance
Hair loss can significantly impact quality of life and self-esteem. While often genetic or age-related, it can also signal underlying medical conditions requiring treatment. Tracking onset and progression provides valuable clinical context.
Types of hair loss:
- Androgenetic alopecia: Male/female pattern baldness (genetic)
- Telogen effluvium: Diffuse shedding after stress, illness, or hormonal changes
- Alopecia areata: Autoimmune patchy hair loss
- Anagen effluvium: Sudden loss during active growth (chemotherapy)
- Traction alopecia: From tight hairstyles
- Cicatricial alopecia: Scarring hair loss
Common causes include:
- Hereditary (androgenetic alopecia)
- Hormonal changes (pregnancy, menopause, thyroid disorders)
- Nutritional deficiencies (iron, zinc, biotin, protein)
- Physical or emotional stress (telogen effluvium)
- Autoimmune conditions (alopecia areata, lupus)
- Medications (chemotherapy, blood thinners, retinoids, beta-blockers)
- Scalp conditions (fungal infections, psoriasis)
- Post-COVID-19 hair loss
- Rapid weight loss
When to Seek Medical Attention
Users should consult a healthcare provider when hair loss:
- Is sudden or occurs in clumps
- Creates bald patches
- Is accompanied by scalp pain, itching, or burning
- Occurs with other symptoms (fatigue, weight changes, skin changes)
- Follows medication changes
- Is accompanied by nail changes
- Affects eyebrows, eyelashes, or body hair
- Is associated with scarring of the scalp
- Causes significant emotional distress
Pattern Recognition
Clinicians can use longitudinal data to identify:
- Temporal relationship to stressors (telogen effluvium typically starts 2-3 months after trigger)
- Correlation with menstrual cycle or pregnancy
- Seasonal shedding patterns
- Medication-related onset
- Post-illness hair loss (post-COVID)
- Response to nutritional supplementation
- Treatment effectiveness tracking
Caveats & Limitations
- Pattern of hair loss (diffuse vs. patchy) not captured
- Location of hair loss not recorded
- Cannot quantify amount of hair shed
- Does not capture scalp symptoms (itching, pain)
- Subjective perception may not match objective assessment
- Hair cycle changes are delayed (effects appear months after cause)
- Does not differentiate between hair types (scalp, body)
- Cannot assess for scarring