Vitiligo shows up as smooth, well-defined patches of skin that have lost their color, turning lighter or completely white. These patches most commonly appear first on the hands, face, and areas around body openings like the mouth, nostrils, and genitals. If you’ve noticed one or more pale spots with distinct edges that don’t fade or change with moisturizing, sun exposure, or time, vitiligo is a real possibility, especially if the patches are spreading.
What the Patches Look Like
The earliest sign is usually a single area of skin that looks noticeably lighter than the surrounding skin. Over time, it may become completely white. Unlike a rash or dry patch, vitiligo patches are flat and smooth. They don’t itch, flake, or feel different in texture. The edges tend to be sharply defined, creating a clear border between pigmented and depigmented skin. On lighter skin tones, the contrast can be subtle at first and more obvious after sun exposure, when surrounding skin tans but the affected area stays pale or burns easily.
Vitiligo doesn’t only affect exposed skin. White patches can develop inside the mouth, on the lips, and on the genitals. You may also notice premature graying or whitening of hair on your scalp, eyebrows, eyelashes, or beard. Hair growing within a depigmented patch often turns white as well, since the same pigment-producing cells are affected in the hair follicles.
Where Patches Typically Start
The hands and face are the most common starting points. Areas that experience regular friction or pressure, like the wrists, elbows, knees, and ankles, are also frequent early sites. This is partly due to something called the Koebner phenomenon: skin injury, even minor friction, scratching, or sunburn, can trigger new patches of color loss at the site of damage. These injury-triggered patches tend to appear within 10 to 20 days and often run in a straight line following the shape of the wound or irritation.
This means you might first notice vitiligo at the site of a cut, a tattoo, or an area where clothing rubs against your skin. If you’ve seen new pale spots appear after a sunburn or scrape, that pattern is worth paying attention to.
Patterns That Help Identify the Type
Vitiligo follows a few recognizable patterns, and the one you have affects how it’s likely to behave over time.
Non-segmental vitiligo is the most common form. Patches appear symmetrically on both sides of the body, such as both hands, both knees, or both sides of the face. It tends to spread slowly, with new patches developing on and off over years or even decades.
Segmental vitiligo behaves differently. It affects only one side or one section of the body, like one arm, one leg, or one half of the face. It spreads quickly, usually over 6 to 12 months, then stops. Once it stabilizes, most people with this type don’t develop new patches. Segmental vitiligo is more common in children.
A smaller number of people develop both patterns at once, which is called mixed type vitiligo.
When It Usually Appears
Vitiligo can start at any age, but it often begins before 30. About 30% of all vitiligo cases start during childhood or adolescence. In one large study, roughly 21% of patients first developed vitiligo before age 12, with an average onset around age 6. The condition affects all skin tones and ethnicities equally, though it’s more visually apparent on darker skin.
How Doctors Confirm It
A dermatologist can usually identify vitiligo by examining your skin. One of the most useful tools is a Wood’s lamp, a handheld ultraviolet light used in a darkened room. Under this light, depigmented skin glows bright blue-white, making even subtle patches visible that might be hard to see under normal lighting. This is especially helpful for people with fair skin, where early patches can be easy to miss.
In most cases, the visual exam and Wood’s lamp are enough. If there’s any uncertainty, a small skin biopsy can confirm the diagnosis. Under a microscope, vitiligo skin shows a complete absence of melanocytes, the cells responsible for producing pigment. This distinguishes it from other conditions where melanocytes are still present but underactive.
Your doctor will also likely measure how much of your body is affected. The standard tool for this is the Vitiligo Area Scoring Index, which estimates the percentage of body surface area with color loss. It uses your own fingertip as a measuring unit: the area from your last finger joint to your fingertip equals roughly 0.03% of your total body surface. This measurement helps track whether the condition is stable or progressing.
Conditions That Look Similar
Several other skin conditions cause lighter patches and can be mistaken for vitiligo. Tinea versicolor, a common fungal infection, creates lighter spots but they tend to have a slightly scaly texture and respond to antifungal treatment. Pityriasis alba, especially common in children, causes pale patches with fuzzy edges, usually on the face, that resolve on their own. Post-inflammatory hypopigmentation happens after a skin injury or eczema heals, leaving a lighter area that gradually fades back to normal.
The key differences with vitiligo are the sharp, well-defined borders, the complete loss of color rather than just lightening, the smooth texture, and the tendency to spread symmetrically.
The Autoimmune Connection
Vitiligo is an autoimmune condition. The immune system mistakenly attacks and destroys melanocytes, which is why the color loss is permanent unless treated. Because of this autoimmune mechanism, vitiligo frequently occurs alongside other autoimmune conditions. People with vitiligo are significantly more likely to develop Hashimoto thyroiditis (about 5 times the risk of the general population) and alopecia areata, a condition that causes patchy hair loss (about 9 times the risk).
About 3% of people with vitiligo also have type 1 diabetes. If you’re diagnosed with vitiligo, your doctor will likely check your thyroid function through a blood test, since thyroid problems are the most common associated condition and can be managed easily once detected.
What to Watch For Over Time
Vitiligo patches can remain stable for months or years, then suddenly expand. Stress, skin injuries, and severe sunburns are common triggers for new patches. If you notice white spots spreading to new areas, appearing symmetrically, or developing at sites of recent skin damage, these are strong indicators that the condition is active.
Some people notice a subtle “confetti-like” pattern of tiny white spots at the edges of existing patches. This often signals active spreading. Others see a halo of lighter skin developing around a mole before it turns fully white, known as a halo nevus, which can be an early sign of vitiligo even before larger patches appear.
Keeping a photo record of your patches over time gives you and your dermatologist a clear picture of whether the condition is stable or progressing, which directly affects treatment decisions.