Causes of vitiligo

Vitiligo happens when the cells that make skin pigment (melanocytes) are destroyed or stop working - and the strongest evidence points to an autoimmune process, not to food, infection or anything contagious.

The core mechanism - autoimmune. In most people with vitiligo, the immune system mistakenly attacks melanocytes. Why this starts is not fully understood; genes play a role (vitiligo can run in families), and it is associated with other autoimmune conditions, especially autoimmune thyroid disease. Checking thyroid function is a routine part of a new vitiligo workup for this reason.

Other contributing ideas. Oxidative stress in pigment cells, nerve-related factors (especially in segmental vitiligo), and a trigger event - a sunburn, skin injury (new patches can appear at injury sites, called the Koebner phenomenon), or major emotional stress - are all thought to contribute in susceptible people.

What does NOT cause vitiligo: it is not an infection and cannot spread by touch, sharing food, or living together. It is not caused by eating specific food combinations - the popular belief that milk with fish (or curd, citrus, or 'sour' foods) causes white patches has no scientific basis. It is not leprosy, not a sign of internal poisoning, and not caused by cosmetics in the usual sense (though certain harsh chemicals, like some phenolic compounds in industrial products, can trigger depigmentation).

Who gets it: all skin types, all ages, roughly equal in men and women; it is simply more visible - and more socially distressing - on darker skin, which is part of why it is so prominent a concern in India.

Ayurvedic view (interpretive): classical texts describe white-patch disease as shwitra or kilasa, attributed to dosha imbalance and incompatible-food theories. This is a traditional interpretive framework with limited evidence; modern understanding identifies autoimmunity as central. The incompatible-food explanations in classical texts are a cultural source of the milk-and-fish myth - they should not be read as proven causes.

Remember: vitiligo is an autoimmune loss of pigment cells - not contagious, not an infection, and not caused by milk, fish or food combinations. Family history and thyroid autoimmunity are the real associations to know.