You’re getting dressed, and you notice them:
tiny white dots scattered on your arms or legs—more visible now that your summer tan is fading.
At first, you wonder: Is it a fungus? A vitamin deficiency? Something serious?
Take a breath.
In most cases, these spots are harmless, common, and completely normal—especially as you age.
Here’s what’s really going on—and when (if ever) you should see a doctor.
🌞 What Are These White Spots?
They’re likely Idiopathic Guttate Hypomelanosis (IGH)—a mouthful of a name for a simple, benign condition.
“Idiopathic” = unknown cause (though we know sun plays a big role)
“Guttate” = drop-like (they’re small and round)
“Hypomelanosis” = reduced pigment (melanin)
✅ Key facts:
Flat, smooth, 1–5 mm in size
Most common on sun-exposed areas: arms, legs, shoulders, face
Appear in 50–80% of people over 40
More noticeable on tanned or olive skin—but occur in all skin tones
☀️ Why Do They Appear? The Sun Is the Main Culprit
Over time, UV radiation damages melanocytes—the cells that produce skin pigment.
In small areas, these cells stop working or disappear entirely, leaving behind patches with no melanin.
Think of it like “sunburn scars” for your pigment system—not dangerous, but a sign of cumulative sun exposure.
📌 Note: Genetics also play a role—some people are just more prone to IGH.
