Causes of Hair Fall: 10 Common Reasons for Hair Loss

Hereditary Hair Loss (Genetic Factors)

If your father, uncle, or maternal grandfather experienced hair thinning, you likely will too. Hereditary hair loss, clinically called androgenetic alopecia, is the most common reason for hair loss worldwide.

• In men, it follows a predictable pattern: temples recede first, then the crown thins.
• In women, hereditary hair loss usually presents as diffuse thinning across the top of the scalp rather than a defined pattern.

A hormone called DHT (dihydrotestosterone) binds to genetically sensitive hair follicles and gradually miniaturizes them. Over time, those follicles stop producing hair entirely. Genetic hair loss responds well to early treatment that blocks DHT activity and stimulates follicle health.

Hormonal Imbalance & Hair Loss

When hormones shift, hair often takes the hit first. Hair loss from hormone imbalance can stem from several conditions:

• Thyroid dysfunction disrupts the hair growth cycle, causing diffuse shedding
• PCOS (Polycystic Ovary Syndrome) elevates androgens in women, triggering male-pattern-like thinning
• Postpartum hormonal drop: Oestrogen levels fall sharply after childbirth, pushing large numbers of hairs into the shedding phase
• Perimenopause and menopause reduce oestrogen over time, thinning hair progressively

Up to 50% of women experience noticeable hair thinning at some point in their lives, and hormonal imbalance is among the top causes. A simple blood panel covering thyroid function, androgens, and iron levels can reveal the issue correctly.

Stress Can Cause Hair Loss

Stress can cause hair loss through a specific, well-documented process. When your body experiences physical or emotional stress — surgery, illness, or major loss — it can trigger Telogen Effluvium: a condition where a large percentage of hair follicles simultaneously shift from the active growth phase into the resting phase.

Six to twelve weeks later, that hair starts falling out in large amounts. Because the timing is delayed, most people never connect the shedding back to the original stressor.

Nutritional Deficiencies

Your hair follicles are among the most metabolically active cells in your body. They need a steady nutrient supply to produce strong, healthy hair. Common deficiencies linked to hair fall:

Sudden Hair Loss (Medical or Lifestyle Triggers)

Sometimes hair loss is sudden and alarming. The reason for sudden hair loss is often a physiological shock to the system. Triggers that you might not be aware of:

• Major surgery or hospitalisation
• Extreme crash diets or prolonged caloric restriction
• Certain medications — beta blockers, antidepressants, blood thinners, retinoids, and some contraceptives

If you've recently recovered from a serious illness or changed medications and are noticing rapid shedding, connect those dots and discuss it with a hair specialist.

Reasons for Sudden Hair Loss in Males

Sudden hair loss among males can be triggered by the following:

• DHT sensitivity: Your genes make your hair react strongly to DHT hormones, causing faster hair loss and thinning than expected
• High-protein supplement misuse: Some workout supplements boost hormones that trigger more hair shedding
• Sleep deprivation and chronic work stress: Poor sleep and constant stress disrupt your hormones and speed up hair loss
• Scalp inflammation: Bad scalp hygiene or skin conditions weaken hair roots from the inside

Poor Hair Care Routine

Sometimes damage is self-inflicted through habits that seem harmless. Practices that damage hair and scalp health:

• Excessive heat styling weakens the hair shaft and increases breakage
• Chemical treatments strip the hair's protective layer
• Over-washing removes natural scalp oils, causing the scalp to become dry and reactive
• Tight hairstyles cause traction alopecia, a form of hair loss from mechanical stress

None of the above cause permanent hair loss on their own. But combined with genetic predisposition, they can accelerate noticeable thinning.

Scalp Infections & Conditions

Like any skin, the scalp can develop infections and inflammatory conditions that interfere with hair growth.

• Dandruff (Seborrheic Dermatitis): Chronic inflammation around follicles weakens the hair root
• Fungal infections (Tinea Capitis): Cause patchy hair loss, scalp itching, and scaling
• Psoriasis: Autoimmune-driven scaling and inflammation that disrupts the follicle environment

Most scalp conditions are highly treatable once properly diagnosed. The mistake is treating symptoms with over-the-counter shampoos for months without consulting a dermatologist.

Medical Conditions & Medications

Medical conditions that can be the reason for hair loss:

• Alopecia Areata: Your immune system mistakenly attacks your hair follicles, causing patchy hair loss
• Lupus and autoimmune disorders: These conditions cause your body to attack itself, leading to heavy hair shedding
• Anaemia and chronic illness: When your body lacks oxygen or nutrients, your hair follicles don't get what they need to grow
• Chemotherapy: Cancer treatment drugs are strong enough to damage hair follicles along with cancer cells

Aging & Natural Hair Thinning

With age, the hair growth cycle naturally slows. Follicles that once produced thick, pigmented hair gradually produce thinner, shorter strands.

This begins in the 30s and becomes more visible in the 40s and 50s due to reduced scalp circulation, declining hormone levels, and cumulative follicle fatigue.