SkincareSafety Guide

Skin

Understand your skin type, tone, and what your skin is doing.

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Skin typesThe main skin types and how they differ.Find your skin typeA practical identification guide.What different skin types look likeVisual differences between common skin types.

Common skin questions

Oily skinWhat oily skin means and how to read it.Skin type changesHow skin type can shift over time.Skin type and ageHow visible aging differs by skin type.
Not sure where to start?Use the skin-type guide before choosing routines or ingredients.

Concerns

Start from a skin problem or visible change.

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Oil and acne

Why oily skin happensThe main drivers behind excess oil.Oily skin and acneHow oil can contribute to breakouts.Can oily skin cause acne?A direct answer to the oil-acne link.

Changes and warning signs

Stress and oily skinHow stress may affect oiliness.Dehydration and oilinessWhy skin can feel oily and dehydrated.Skin cancer signsVisual signs that need professional attention.
Looking for a solution?Start with what oily skin actually needs before adding stronger products.

Ingredients

Understand what ingredients do and whether they fit your skin.

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Explore ingredients

NiacinamideA practical ingredient overview.Vitamin C serumWho can use vitamin C and when to be careful.RetinolHow retinol fits different skin types.

Use safely

Salicylic acidWhere this acne-focused ingredient fits.Niacinamide for all skin typesSuitability across skin types.Ingredient comparisonsUse comparisons to avoid mismatched decisions.
Can my skin use this?Browse compatibility questions before adding a new active.

Routines

Turn skin information into daily decisions.

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Daily basics

Does every skin type need moisturizer?A basic routine decision.Does every skin type need sunscreen?Where SPF fits in daily care.What oily skin needsA simple care direction for oily skin.

Adjust over time

Skin changes with ageWhen your routine may need to change.Seasonal skin changesHow weather affects skin behavior.Korean skincare approachWhat is useful beneath the trend.
Starting from scratch?Begin with moisturizer, sunscreen, and one skin-specific need.

Products

A small selection of skincare products recommended by OuterDerm for simple, effective everyday routines.

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Recommended picks

Daily SunscreenDaily UV protection that has to be wearable enough to stick with.Azelaic AcidA focused 10% azelaic acid when uneven tone or blemish marks are the concern.Gentle CleanserComfortable cleansing when tight or squeaky skin is a warning sign.
Not sure where to start?Browse three carefully selected essentials, then ask on WhatsApp before you order.

Learn

Go deeper into skin science, myths, evidence, and safety.

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Hazardous ingredients

Safety hubStart with mercury, steroids, PPD and other hazardous substances.Ingredient safety indexBrowse Phase 1 and Phase 2 hazardous ingredients.Mercury in whitening creamsLabel names, Punjab alerts, and what to do now.

Product literacy

Product literacy hubHow to read labels, claims, and INCI lists before you buy.How to read an ingredient labelINCI order, Parfum, and missing-list red flags.Fragrance-free vs unscentedHow to verify a fragrance-free claim on the ingredient list.How to choose sunscreenBroad spectrum, wearability, and a readable pack — not a fairness claim.

Skin science

Skin color geneticsHow inherited traits shape skin color.Skin color typesHow skin tone is commonly grouped.Are skin types genetic?What genetics can and cannot explain.

Evidence and myths

Can all skin types tan?Tanning, risk, and skin type.Is oily skin good or bad?A balanced view of oily skin.Why Korean skin looks flawlessTrend claims translated into practical basics.
Want the evidence layer?Use why-guides when you want causes, mechanisms, and context.

Skin Conditions

Why Does Melasma Occur on the Face?

Melasma has a favorite location, and it's not random. The face is the most common site for a variety of reasons, each rooted in skin biology and environmental exposure.

The sun has a favorite canvas, and it's your face. It's the part of your body that catches the most UV rays, but that's only half the story.

Why, out of all the sun-exposed skin on your body, is your face the main stage for melasma?

The answer lies in a perfect storm of skin biology.

Think of your face as prime real estate for melasma. It has the highest property value (lots of pigment cells and hormone receptors) and gets the most wear-and-tear from the sun.

Quick answerMelasma occurs on the face for several reasons.

Medically reviewed by Dermatology reviewer · Updated Jul 19, 2026 · 7 min read

A woman with melasma on her cheeks, forehead, and upper lip
Primary LocationFace (cheeks, forehead, upper lip)
Reason 1High UV Exposure
Reason 2More Hormone Receptors
Reason 3High Concentration of Melanocytes
Other LocationsNeck, forearms (less common)

Key answer

Well explained

Melasma occurs on the face because it's the most sun-exposed, sensitive, and biologically primed area of the body for this type of pigmentation.

Evidence
Moderate - Well explained
Best for
Anyone who has melasma and wants to understand why it's on their face; Those looking to understand the science behind their specific pigmentation pattern

See what the evidence shows

Short version

Story in brief

Melasma is a condition of contrast - it shows up on some parts of the skin and not others, and its primary stage is the face. This isn't random. The face is a special case in skin biology. It's the part of the body that is most consistently exposed to the sun and has a unique distribution of cells and receptors.

The face has a higher density of melanocytes, the pigment-producing cells, than many other areas. It also has a greater number of receptors for hormones like estrogen and progesterone. This means that when the sun's UV radiation hits the face, and when hormones are fluctuating, the reaction in the facial skin is stronger and more sustained than in other areas.

The results are predictable: melasma tends to appear on the cheeks, forehead, and upper lip - the areas that catch the most sun and are most sensitive to hormonal changes. This is why it's sometimes called the "mask of pregnancy" - it follows the contours of a face, forming a distinctive pattern.

Mental model

Visual explanation

Evidence

What the evidence shows

Melasma's preference for the face is not a coincidence. The face is a hotspot for all three triggers: it gets the most sun, it has the most pigment cells, and it is the most sensitive to the hormonal signals that drive the condition.

Use this section to decide

Does this advice apply to me?

Find the concern or goal closest to yours, then use the fit signal to decide how much weight to give this guide.
Strong fit means the advice is central to that goal.Depends means formula, tolerance, or context matters more.Use caution means do not treat it as the main answer.

  • If your goal is

    Primary SiteUse caution
    Fit signal
    Limited evidence

    Face

  • If your goal is

    Key FactorsDepends
    Fit signal
    Possible fit

    UV, Hormones, Melanocyte Density

  • If your goal is

    Common AreasUse caution
    Fit signal
    Limited evidence

    Cheeks, Forehead, Upper Lip

  • If your goal is

    Why the Face?Use caution
    Fit signal
    Limited evidence

    It's the most sensitive and exposed area.

Research notes already in this guide

  • Clinical observations consistently show melasma affecting the face in over 90% of cases.
  • The condition often follows a mask-like distribution, specifically targeting the cheeks, forehead, and upper lip.
  • The pattern of melasma often mirrors the areas of the face that receive the most UV exposure.

Explanation

How it works

This diagram shows the confluence of factors that make the face the primary location for melasma.

  1. High UV Exposure

    The face is the most sun-exposed area, providing the initial trigger for melanin production.

  2. High Melanocyte Density

    More pigment cells mean more potential for overproduction in response to the UV trigger.

  3. Sensitivity to Hormones

    Facial melanocytes are more responsive to hormonal signals, making the overproduction more persistent.

  4. Thinner Skin

    The facial skin's thinner layers make the deposited pigment more visible, leading to the characteristic dark patches.

Practical use

How to use it

  1. Face-Specific Sun Protection

    Apply a high-SPF, broad-spectrum sunscreen to your face every day, and reapply every two hours. Consider a sunscreen with iron oxides for protection against visible light.

  2. Use a Targeted, Gentle Routine

    Avoid harsh scrubs or cleansers on your face that can cause irritation and worsen pigmentation. Stick to gentle, barrier-supporting products.

  3. Consult a Dermatologist for Facial Treatments

    A dermatologist can offer prescription topicals or in-office procedures (like peels or lasers) that are specifically designed for the delicate and sensitive skin of the face.

Safety

Side effects and cautions

  • Applying sunscreen only to the body and not the face

    The face is the most common site for melasma, so it requires the most diligent sun protection.

  • Thinking that melasma on the face is caused by poor facial hygiene

    Melasma is not caused by hygiene but by internal and external factors like UV and hormones.

  • Focusing on body pigmentation treatments and ignoring the face

    The face has a different biology from the body and requires a targeted approach to treatment.

Worth noting

Small details that can change the answer

  • The Face Gets the Most Sun. It's the most frequently exposed part of the body, making it the primary target for UV-induced melasma.
  • A Hub of Hormonal Activity. Facial skin is particularly responsive to hormonal changes, which is why melasma can flare during menstrual cycles.
  • Melanocyte Concentration. Certain areas of the face, like the cheeks and forehead, have a higher density of melanocytes than other body parts.
  • Thinner Skin, Bigger Impact. The skin on the face is thinner than many other areas, making pigment changes more visible.

Melasma occurs primarily on the face due to high UV exposure and the face's unique biology.

The face has a higher density of melanocytes and more hormone receptors than other body parts.

This makes facial skin more sensitive to the UV and hormonal triggers of melasma.

The condition typically appears on the cheeks, forehead, and upper lip.

A targeted, face-specific approach to sun protection and treatment is essential.

Explanation

Why the Face is the Main Stage

Melasma primarily occurs on the face because of the interplay of three key factors that are more pronounced there. The first is UV exposure: the face is the most consistently sun-exposed area of the body. The second is the biological makeup: facial skin has a higher density of pigment-producing cells (melanocytes) and is more sensitive to hormonal signals. The third is the skin's architecture, which makes it more susceptible to pigmentation. All of these factors make the face the primary location for melasma development.

Science

The Biology of Facial Skin

The skin on your face is not the same as the skin on your arms or legs. It's thinner, has more sebaceous glands, and crucially, has a higher number of melanocytes per square inch. These cells are also more sensitive to stimulation from UV radiation and hormones. This is why a small amount of sun exposure or a minor hormonal shift can produce a visible pigment change on the face, while the same stimulation might not have any effect on the skin of your back.

Melanocyte Density
The number of pigment-producing cells in a given area of skin. This is higher on the face.
Hormone Receptors
Proteins on the surface of cells that allow hormones to bind and exert an effect. There are more of these on the face.

Questions

Frequently asked questions

Why does melasma only occur on my face?

While it can occur elsewhere, the face is the most common site due to its high UV exposure and biological makeup. If you only have it on your face, you're in the majority.

Why does melasma occur on my cheeks and forehead?

These are the most sun-exposed areas of the face, with a high concentration of melanocytes and hormone receptors. They are the most sensitive to triggers.

Can melasma occur on the upper lip?

Yes, the upper lip is a classic location, often referred to as a "sun mustache." It's a highly sun-exposed area.

Why is my melasma worse on one side of my face?

This is often due to uneven sun exposure, such as from driving in a car, where the side of your face facing the window gets more UV damage.

References

Sources

The notes below are drawn from the evidence already cited in this guide. They are not a complete bibliography.

  1. Clinical observations consistently show melasma affecting the face in over 90% of cases.
  2. The condition often follows a mask-like distribution, specifically targeting the cheeks, forehead, and upper lip.
  3. The pattern of melasma often mirrors the areas of the face that receive the most UV exposure.