The most common cause: idiopathic guttate hypomelanosis
The medical name is a bit complicated, but the condition itself is simple: idiopathic guttate hypomelanosis (often called IGH).
Let’s analyze in detail:
Idiopathic – The cause is not entirely clear
Guttata – From the Latin “teardrop-shaped”
Hypomelanosis – Loss of skin pigment
I wait:
Small, flat white spots, usually 1-5 mm
Most common on sun-exposed areas: shins, forearms, shoulders
Smooth texture (not flaky or raised)
More common with increasing age (often starting in your 40s)
What are the causes?
Although the exact cause is unknown, guttate hypomelanosis is strongly associated with:
Sun exposure for many years (it is more common on sun-exposed skin)
Natural aging – spots become more common as we age
Genetics – some people are simply more predisposed
Is it harmful?
No. Guttate hypomelanosis is completely harmless. It doesn’t turn into skin cancer, doesn’t spread to other people, and doesn’t affect overall health. It’s a purely cosmetic issue.
Other possible causes of white spots
Although IGH is the most common explanation, white spots can sometimes indicate other conditions:
1. Tinea Versicolor
This is a fungal infection caused by a yeast that lives naturally on the skin. When it overgrows, it can cause:
White, pink or tan spots
Often on the chest, back and shoulders
They may be slightly scaly
More noticeable in summer (yeast prevents tanning)
Treatment: Over-the-counter antifungal creams or shampoos often solve the problem.
2. Vitiligo
An autoimmune condition in which the immune system attacks the pigment-producing cells (melanocytes):
Larger, irregular patches of complete loss of pigment
They can appear anywhere on the body
Often symmetrical (present on both sides)
They can be hereditary
