Estresse e queda de cabelo: guia do eflúvio telógeno

Telogen effluvium (TE) occurs when a significant stressor pushes a large number of hair follicles into the resting (telogen) phase simultaneously. A groundbreaking 2021 study published in Nature identified the precise mechanism:

• Corticosterone pathway: The stress hormone corticosterone (cortisol in humans) directly acts on the dermal papilla cells that regulate the hair follicle stem cell niche, keeping follicles in an extended resting phase.
• GAS6 protein: Stress hormones suppress a molecule called GAS6 in the dermal papilla, which is normally responsible for activating hair follicle stem cells to begin a new growth cycle.
• Delayed onset: Because hair remains in the telogen phase for 2-4 months before falling out, the connection between the stressor and hair loss is often not immediately apparent.

Common triggers for telogen effluvium include:

• Severe illness, surgery, or high fever (including COVID-19 — reported in 20-30% of survivors)
• Emotional trauma, grief, or psychological stress
• Crash dieting or rapid weight loss
• Childbirth (postpartum telogen effluvium)
• Medication changes, particularly starting or stopping hormonal contraceptives
• Iron deficiency or other nutritional deficiencies

Distinguishing telogen effluvium from other causes of hair loss is important for appropriate management:

• Pattern: TE causes diffuse thinning across the entire scalp, not patches or a receding hairline. Hair comes out evenly from all areas, including the sides and back.
• Timing: If you can identify a significant stressor 2-4 months before the shedding began, TE is likely.
• Pull test: A dermatologist may perform a hair pull test — gently pulling a group of about 60 hairs. In active TE, more than 10% (6+ hairs) will come out, mostly with white bulbs at the root (indicating telogen phase).
• Shedding volume: Normal shedding is 50-100 hairs per day. TE may increase this to 200-500+ hairs per day.

When to seek medical evaluation:

• Shedding persists beyond 6 months (may indicate chronic TE or another condition)
• Patchy hair loss (may be alopecia areata)
• Scalp symptoms like pain, burning, or redness
• Associated symptoms like fatigue, weight changes, or menstrual irregularities (thyroid evaluation needed)

WAYJET's Health Chat can help you assess your symptoms and determine whether medical evaluation is warranted.

The most important treatment for TE is identifying and addressing the underlying trigger. In most cases, TE is self-limiting:

• Acute TE (most common): Resolves within 6-12 months once the trigger is removed. No specific treatment is usually necessary beyond patience and reassurance.
• Chronic TE: Lasting longer than 6 months. May require investigation for ongoing triggers such as nutritional deficiencies, thyroid dysfunction, chronic stress, or medication effects.

Supportive measures during recovery:

• Nutritional support: Ensure adequate iron (ferritin >30 ng/mL), vitamin D (>30 ng/mL), zinc, and protein intake. Nutritional optimization may accelerate recovery.
• Stress management: Cognitive behavioral therapy (CBT), mindfulness meditation, regular exercise, and adequate sleep (7-9 hours) help reduce cortisol levels.
• Gentle hair care: Minimize mechanical stress — avoid tight hairstyles, excessive brushing, and heat styling during the shedding phase.
• Minoxidil (optional): Some dermatologists prescribe topical minoxidil during TE to stimulate regrowth. A 2017 study found it shortened the recovery period, though TE resolves without it.

Avoid the trap of starting multiple new supplements and treatments simultaneously — this makes it impossible to identify what is actually helping and may introduce new triggers.