What makes skin dark?

What makes people's skin dark?

People with naturally darker skin produce more melanin. Melanocytes exist in normal skin across skin tones; the difference is not simply whether those cells are present. In darker skin, melanin is also distributed through the outer skin layer, called the epidermis. Skin makes mostly eumelanin, a brown to black pigment, and a smaller amount of another pigment called pheomelanin. The amount and depth of melanin affect the color you see. Melanin also helps protect skin against damage from ultraviolet radiation, so pigment has a job beyond appearing on foundation shade charts. Not every color change is melanin. Blood pigments, carotene and other substances contribute to skin color, and skin thickness can affect its appearance. Naturally dark skin and skin that has become darker than usual are different questions: the second calls for looking at what changed.2

Why has your skin become darker?

Hyperpigmentation means extra darkening from excess melanin. Pigmentation changes can affect a small patch or much of the body. Sun exposure and pregnancy can increase pigmentation; Addison's disease can also cause darkening. Inflammation and friction promote melanin production. Dark marks can remain after a pimple clears or a cut, burn or insect bite heals. Irritating skin or hair products can trigger marks too, which is an awkward result for something bought to improve the situation.34

What causes dark, thick patches in skin folds?

Acanthosis nigricans causes patches that are darker and thicker than the surrounding skin. They often feel dry and velvety, develop gradually and sometimes itch. Small skin tags can appear on the patches. Obesity is the most common cause. Other causes include type 2 diabetes, hormone disorders, an underactive thyroid and certain medicines, including steroids and hormone treatments. Healthy people can develop these patches too, particularly people with black or brown skin. Rarely, acanthosis nigricans is associated with cancer. A doctor can often recognize the condition by examining the skin, but tests can help identify its cause. Treatment focuses on that cause rather than just changing the patch's appearance. Depending on the findings, treatment can involve weight management, medicines affecting hormones or insulin, or a change of medication. The patches should fade over time once the cause is treated. Arrange an appointment for new dark patches or skin changes you are unsure about.67

Can pregnancy or hormones make skin darker?

Pregnancy can trigger melasma, which causes uneven pigmentation. Birth control pills, sunlight and stress can also trigger melasma. Sunlight increases pigment production and can darken existing patches or cause new ones. Melasma sometimes fades after pregnancy ends or another trigger is removed, but it can last for years or a lifetime. Melasma itself does not harm the body. A dermatologist can confirm the diagnosis and assess how deeply the pigment sits, sometimes using a special light or viewing device. Treatment aims to reduce excess pigment and restore the skin's natural color. There is no single best treatment. A plan usually combines sun protection with medication applied to the skin, and sometimes a procedure. Skin tone, pigment depth and triggers help determine the choice. Prescription options include hydroquinone and creams combining hydroquinone, tretinoin and a corticosteroid. A dermatologist can also choose gentler options such as azelaic acid. For melasma, apply prescribed medication first, sunscreen second and camouflage makeup last. Makeup can hide discoloration while treatment works; it is camouflage, not a resignation letter from the pigment. Melasma treatment usually takes 3 to 12 months to show results, and longer when pigmentation has been present for a long time. Chemical peels, microneedling and laser or light treatments require a dermatologist with the expertise to select and perform them safely.5

How can you make dark skin lighter?

For newly darkened areas, treatment depends on the cause. Lightening creams can help some discoloration, but darker skin needs greater care with these preparations. Follow the product or prescription instructions carefully rather than treating every dark patch the same way.1

1. 1First, address the trigger. Treat an ongoing skin condition causing marks and replace irritating skincare with gentler products. If a product burns or stings, stop using it.
2. 2Before going outside, apply tinted sunscreen containing iron oxide to skin clothing will not cover. Choose SPF 30 or higher, broad spectrum protection and water resistance. Iron oxide helps protect against visible light, which can cause dark spots.
3. 3Reapply sunscreen every two hours and after swimming or sweating. Wear a wide brimmed hat outdoors and avoid the strongest sunlight, between 10 a.m. and 2 p.m.
4. 4Once the trigger is controlled and sun protection is in place, consider a dark spot treatment. Ingredients used for fading spots include azelaic acid, glycolic acid, kojic acid, retinoids and vitamin C.

How long do dark marks take to fade?

After the trigger stops, a spot a few shades darker than your natural skin color usually fades within 6 to 12 months. Deeper pigment can take years and often looks slate blue, gray or much darker brown. Treatment can speed fading, but new spots can develop if the trigger returns.4

When should a doctor check darkening skin?

Book an appointment for persistent, unexplained darkening, discoloration that concerns you, or a sore or lesion changing shape, size or color. A changing lesion can be a sign of skin cancer. Medicines including minocycline, some cancer treatments and birth control pills can cause pigmentation changes. Do not stop prescribed medication yourself; ask the prescriber whether darkening is a possible side effect and whether an alternative is appropriate. Tell the doctor when the change started, whether it is spreading, what medicines you take and whether you have other symptoms. Depending on the findings, assessment can include blood iron levels, hormone or thyroid tests, or a skin biopsy.14

Never apply liquid bleach to skin. Some imported lightening products have contained mercury or steroids missing from their labels. Unsupervised, prolonged use of these steroids can leave skin thin, fragile or permanently discolored. Choose a lightening product recommended by a dermatologist.4