Vitiligo happens when your body stops making melanin in patches of skin

Vitiligo occurs when the cells that produce melanin—the pigment that gives your skin its color—die or stop working in certain areas. The result is flat, white patches that lack pigment. The patches can appear anywhere on your body, though they often show up first on the face, hands, feet, or areas that get sun exposure or experience friction from clothing.

The exact reason melanin-producing cells (called melanocytes) fail is not fully understood, but research points to several overlapping causes working together. It is not contagious, and it is not caused by poor hygiene or diet. What happens is a breakdown in the system that normally keeps melanocytes alive and functioning.

Key Takeaways

  • Vitiligo develops when melanocytes—the cells that make skin pigment—die or stop producing melanin, leaving white patches behind.
  • Your immune system may attack melanocytes by mistake, which is why vitiligo often runs in families and can appear after stress or injury.
  • Genetics play a role: if a parent has vitiligo, the risk is higher, though not everyone with the genetic predisposition will develop it.
  • Triggers like sunburn, skin injury, emotional stress, or certain medications can speed up pigment loss in people already prone to vitiligo.
  • Vitiligo is not caused by infection, poor hygiene, or diet, and it cannot spread from one person to another.

How your immune system may attack melanocytes

The leading theory is that vitiligo is an autoimmune condition, meaning your immune system mistakenly targets and destroys melanocytes. Normally, your immune system protects you by attacking bacteria and viruses. In autoimmune vitiligo, the system loses the ability to distinguish between harmful invaders and your own healthy cells.

Research has found antibodies—proteins your immune system makes to fight threats—circulating in the blood of many people with vitiligo. These antibodies bind to melanocytes and mark them for destruction. Why this happens in some people and not others remains unclear, but it appears to involve both genetics and environmental triggers.

This autoimmune mechanism explains why vitiligo often appears or worsens after physical or emotional stress, injury to the skin, or a viral infection. These events can activate or amplify the immune response against melanocytes.

Genetic factors that increase your risk

Vitiligo tends to run in families. If one or both parents have vitiligo, your risk of developing it is higher than in the general population. Studies suggest that multiple genes are involved, not just one, which means inheritance is complex and unpredictable.

Having the genes associated with vitiligo does not mean you will definitely develop it. Many people carry these genetic variations without ever showing symptoms. This is why identical twins—who share all their DNA—do not always both have vitiligo. Something else must trigger the condition in people who are genetically susceptible.

Researchers have also found that vitiligo shares genetic overlap with other autoimmune conditions like thyroid disease and type 1 diabetes. People with one autoimmune condition have a slightly higher chance of developing another.

Triggers that can speed up pigment loss

Even if you carry genes that make vitiligo possible, a trigger often precedes the appearance of patches. Common triggers include physical injury to the skin (cuts, burns, tattoos, or surgical scars), severe sunburn, and emotional stress. The connection between stress and vitiligo is well documented: some people notice patches appearing weeks or months after a major life event.

Certain medications can also contribute. Drugs that suppress the immune system or affect skin cells—including some blood pressure medications and antibiotics—have been linked to vitiligo in susceptible people. If you take medication and notice new white patches, discuss this with your doctor rather than stopping the medication on your own.

Friction from tight clothing, repeated rubbing, or pressure on the same area of skin can trigger vitiligo patches in that location. This is called the Koebner phenomenon, and it occurs in other skin conditions as well. The exact mechanism is not known, but it suggests that local skin damage activates the immune response against melanocytes.

Why some patches spread and others stay stable

Vitiligo is unpredictable. In some people, patches appear once and remain stable for years. In others, new patches emerge regularly, and existing ones grow larger. The rate and extent of spread vary widely and cannot be predicted based on the initial patch alone.

Early-onset vitiligo (appearing before age 20) tends to spread more rapidly than late-onset vitiligo. Patches on the face and trunk often progress faster than those on the hands and feet. Stress, sun exposure, and ongoing immune activation appear to drive continued spread, though the exact factors that determine whether your vitiligo will remain stable or progress are not yet fully understood.

Oxidative stress and melanocyte damage

Another theory focuses on oxidative stress—an imbalance between harmful molecules called free radicals and the body's ability to neutralize them. Melanocytes appear to be especially vulnerable to oxidative damage. When free radicals accumulate in the skin, they can injure or kill melanocytes directly, independent of immune attack.

This may explain why sun exposure and skin injury worsen vitiligo: both generate free radicals in the skin. It also suggests why antioxidants—substances that neutralize free radicals—are being studied as a potential treatment approach. The oxidative stress theory does not contradict the autoimmune theory; both processes may occur together in vitiligo.

The role of neural factors

Some research suggests that nerves in the skin may play a role in vitiligo. Certain nerve fibers release chemicals that regulate melanocyte function and survival. Damage to these nerve endings, or changes in the chemicals they release, could contribute to melanocyte loss. This neural theory is less established than the autoimmune and oxidative stress models, but it may explain why vitiligo sometimes follows injury or trauma to a specific area.

The fact that vitiligo often appears in a pattern—sometimes following the distribution of nerves or blood vessels—hints that local tissue factors, not just systemic immune dysfunction, play a role in where patches develop.

Frequently Asked Questions

Can vitiligo be caused by poor diet or hygiene?

No. Vitiligo is not caused by diet, hygiene, or lifestyle choices. It is a condition rooted in genetics and immune system function. While good nutrition and sun protection may support skin health, they cannot cause or prevent vitiligo.

Is vitiligo contagious?

No. Vitiligo is not contagious and cannot spread from one person to another through contact, sharing food, or any other means. It is an internal condition involving your immune system and melanocytes, not an infection.

Can stress alone cause vitiligo?

Stress can trigger or worsen vitiligo in people who are genetically predisposed, but it does not cause vitiligo on its own in people without the underlying genetic and immune factors. Stress appears to activate the immune response in susceptible individuals.

Why did vitiligo appear after I got a tattoo or cut my skin?

This is the Koebner phenomenon: skin injury can trigger vitiligo patches in susceptible people. The injury activates the immune system locally, leading to melanocyte loss in that area. Not everyone with vitiligo experiences this, and not all skin injuries lead to patches.

If my parent has vitiligo, will I definitely get it?

No. Having a parent with vitiligo increases your risk, but many people with the genetic predisposition never develop vitiligo. You would need both the genetic factors and an environmental trigger for the condition to appear.