What Causes Melasma — It's More Complicated Than Just Sun

The Five Triggers of Melasma

Melasma is frustratingly multi-factorial. Blocking one trigger while ignoring the others explains why many patients see incomplete improvement. Understanding all five triggers helps Dr. Ankita create a comprehensive treatment plan — not just a sunscreen prescription.

1. UV Radiation (The Primary Trigger)

UVA and UVB light activate melanocytes (pigment-producing cells) in melasma-prone skin. Even brief sun exposure — 10 minutes without protection — can re-activate faded melasma. In Lucknow, with UV index exceeding 8 for seven months, this is a constant challenge. SPF 50 broad-spectrum sunscreen is non-negotiable, every day, year-round.

2. Hormones

Estrogen and progesterone stimulate melanin production. This explains why melasma frequently appears during: pregnancy (chloasma or mask of pregnancy), oral contraceptive pill use, hormone replacement therapy, and in women with PCOS. The hormonal link is why melasma is 9× more common in women than men.

3. Visible Light (Including Blue Light)

Recent research shows that visible light (particularly blue-violet wavelengths from 400-490nm) triggers melanin production in darker skin tones — even without UV. This means: your phone screen, laptop, indoor LED lights, and sunlight filtered through windows can all stimulate melasma. Regular sunscreens don't block visible light. Only tinted sunscreens (containing iron oxides) or mineral sunscreens with visible-light protection help.

4. Heat

Infrared radiation and heat — from cooking over a gas stove, steam exposure, hot environments — can trigger melanocyte activation independently of light. In Lucknow's 40-45°C summers, ambient heat alone is a trigger. Women who cook daily over open flames often have melasma concentrated on the cheeks closest to the heat source.

5. Inflammation and Pollution

Air pollution particles (PM2.5, PM10, polycyclic aromatic hydrocarbons) generate free radicals in the skin that activate melanocytes. Lucknow's air quality regularly enters "poor" to "very poor" categories — an environmental challenge that compounds UV and hormonal triggers.

The Genetic Predisposition

Not everyone exposed to these triggers develops melasma. There's a significant genetic component — some melanocytes are programmed to overreact to triggers. If your mother or sister has melasma, your risk is substantially higher. You can't change your genetics, but you can control the triggers.

Frequently Asked Questions

Can melasma develop suddenly?

Yes — pregnancy, starting a new contraceptive pill, or a period of intense sun exposure (like a vacation) can trigger melasma seemingly overnight. It was likely sub-clinical before and the trigger pushed it to visible levels.

My melasma comes back every summer. Why?

Melasma is chronic — the melanocytes remain hyperactive even when the visible pigmentation fades. Summer sun (the primary trigger) re-activates them. This is why maintenance treatment and year-round sun protection are essential, not just seasonal efforts.

Can men get melasma?

Yes — about 10% of melasma patients are male. The triggers are the same (UV, genetics), though the hormonal component is less relevant in men. Treatment approaches are identical.