Understanding Sunburn: Why Some Skin Burns Easier Than Others

Sunburn susceptibility varies widely due to intrinsic and extrinsic factors.

Intrinsic Factors

• Fitzpatrick Skin Type I–II: Fair skin, freckles, red/blond hair, blue eyes — minimal melanin, burn easily, never tan.
• Melanin Content: Eumelanin (brown/black) photoprotects; pheomelanin (red/yellow) less effective.
• Genetics: MC1R variants (red hair), DNA repair defects (xeroderma pigmentosum).
• Age: Children and elderly have thinner skin, less melanin, impaired repair.
• Medical Conditions: SLE, porphyria, photosensitivity disorders, immunosuppression.

Extrinsic Factors

• UV Index: Higher at altitude, equator, midday (10 AM–4 PM), summer, reflective surfaces (snow, sand, water).
• Medications: Tetracyclines, fluoroquinolones, sulfonamides, thiazides, retinoids, NSAIDs, amiodarone.
• Topical Agents: AHAs, BHAs, benzoyl peroxide, some essential oils.

Protection Strategies

• Broad-spectrum SPF 30+; apply 2 mg/cm² (1 oz body), reapply q2h.
• UPF clothing, wide-brim hat, UV-blocking sunglasses.
• Seek shade 10 AM–4 PM.
• Review medication photosensitizing potential.

Sunburn is preventable. Cumulative UV damage drives photoaging and skin cancer.