Guide · skin conditions

Seborrheic dermatitis isn’t just dandruff. It’s a balance between skin oil, the microbiome and your skin barrier

Name: Seborrheic dermatitis: when oily skin loses water
Creator: Chicatella Editorial Team
Published: 2026-07-30

On the surface there’s oil. Underneath, there’s skin that loses too much water, plus a yeast that lives on almost everyone’s skin. Seborrheic dermatitis isn’t a story about one culprit. It’s about a balance that’s been thrown off.

Three things worth knowing up front

“Chronic, but manageable. Not contagious. Not caused by poor hygiene.”

Seborrheic dermatitis on the scalp before and after – red, flaky skin along a man’s hairline — Scalp before and after care. The photo shows how the skin looks and is not a diagnosis.

Reading time

≈ 21 min

Published

July 30, 2026

Medically reviewed

July 30, 2026

Author

Chicatella Editorial Team

Medically reviewed by

prim. Jasna Cuk Rupnik, MD

How we put this article together

We base our articles on clinical guidelines, systematic reviews and peer-reviewed research. Every number links to its source, both in the text and in the list at the bottom of the page. This content is educational and doesn’t diagnose anything. Chicatella publishes this article and sells the products shown near the end.

The basics

Start with the short answer

What is seborrheic dermatitis?

A long-lasting inflammatory skin condition in areas with lots of oil glands: the scalp, eyebrows, sides of the nose, behind the ears and the chest. It shows up as redness, itching and white or yellowish flakes that can be greasy or dry. It comes and goes in flare-ups and calm stretches. It’s very manageable, even though it tends to come back, and that doesn’t mean you did anything wrong.DermNet↗︎

Is seborrheic dermatitis a fungal infection?

Not a classic fungal infection. Yeasts called Malassezia normally live on almost everyone’s skin, including yours, even if you have no skin problems at all. Seborrheic dermatitis comes from four things working together: skin oil (sebum), how these yeasts break it down, your own inflammatory response and the state of your skin barrier. So having Malassezia on your skin isn’t a diagnosis on its own.

What’s the difference between dandruff and seborrheic dermatitis?

Dandruff is the milder end of the same spectrum: a flaky scalp with little or no visible redness. Seborrheic dermatitis adds redness, inflammation and often itching, and it can also affect the face, eyebrows, the area behind the ears and the chest. It works the other way too: not all dandruff is seborrheic dermatitis.

Is seborrheic dermatitis contagious?

It isn’t contagious, and it isn’t caused by poor hygiene. You can’t pass it on by touching, hugging or sharing a towel. That’s worth saying out loud, because visible flakes make a lot of people feel embarrassed or guilty, and there’s no reason to.

What actually helps with seborrheic dermatitis?

When seborrheic dermatitis is confirmed, doctors often recommend medicated antifungal shampoos, for example with ketoconazole or ciclopirox, and sometimes a short course of anti-inflammatory treatment. Washing gently and often enough also helps, along with less extra irritation and some patience: calming a flare-up and keeping things calm are two different jobs.Cochrane↗︎

Can it show up on the face, eyebrows and around the nose?

Yes, and it often does. Besides the scalp, typical spots are between and on the eyebrows, the creases beside the nose, behind the ears and in the ear canal, the beard and mustache, the edges of the eyelids, the breastbone and the upper back. The area around the eyes needs extra care, so don’t experiment there on your own. Talk to a doctor.

What it looks like

Seborrheic dermatitis has more than one face

Eight cards: where it shows up, how to recognize it and what makes it worse. Greasy, yellowish flakes on red skin in the areas with the most oil glands are what they all have in common. The sketches are simplified; only a doctor can diagnose it.

Browse→

Where it likes to show up

Scalp, hairline, eyebrows, creases beside the nose, behind the ears and the center of the chest. All of these places have lots of oil glands.

What it looks like up close

Pink or red skin with greasy, yellowish flakes on top. The edge is soft, not sharp. It often itches or stings a little.

Dandruff, or already dermatitis?

Dandruff: small, dry flakes with no redness. Seborrheic dermatitis: red skin and larger, greasy flakes. Same spectrum, different degree.

On the face, it follows the T-zone

Between the eyebrows, in the creases beside the nose and on the chin. The same on both sides, often with flaking in the eyebrows and mustache.

Behind the ears, where it’s easy to miss

The crease behind the ear and the outer ear canal turn red and flaky. A painful crack can form in the crease.

It isn’t always red

On darker skin, the patches are often lighter or darker than the surrounding skin, not red. The flakes and the location tell you more than the color.

It comes and goes

Calm stretches alternate with flare-ups. These are often set off by stress, cold, dry indoor heating and tiredness.

Cradle cap in babies

Thick, yellowish crusts on top of the head that don’t bother the baby. They usually go away on their own in the first year. Oil softens them, and there’s no need to pick at them.

The key finding

Skin can be oily on the surface and still lose water

This is the biggest misunderstanding. When we see an oily scalp, we assume the skin is well hydrated. But those are two completely different measurements.

Skin lipids (sebum)

Oil on the surface of the skin. This is what you can feel and see.

Water in the outer layer

Moisture inside the top layer of skin. You can’t see this.

Water loss (TEWL)

How much water vapor escapes through the skin into the air.

Ability to hold water

How well the barrier keeps water in the skin.

Two separate gauges in the same person

Amount of surface lipids

HIGHER

Ability to hold water

LOWER

A diagram of the direction of the difference, not of measured values.

Oiliness and hydration aren’t the same measurement. Skin can be oily on the surface while its barrier is worse at holding on to water.

A 2019 study compared 42 people with seborrheic dermatitis of the scalp with 40 people without it. The seborrheic dermatitis group had more surface lipids, higher water loss and less water in the outer skin layer.2019 study↗︎ It was a cross-sectional study: it shows a link, not cause and effect. So we can’t conclude from it that skin makes more oil to make up for missing water. The study doesn’t prove that.

Four players

It comes from a relationship, not a single cause

Tap each player. None of them explains the condition alone. It’s how they interact that creates it.

01 · SEBUM AND WHAT IT’S MADE OF

Oil glands on the scalp, face and chest release sebum. It’s not just how much there is that matters, but also what it’s made of, because that decides what’s available on the surface for microorganisms.

A cycle that keeps itself going

Sebum

lots of lipids available on the surface

Microbial byproducts

Malassezia breaks them down, leaving irritating leftovers

Inflammatory response

redness, flakes, itching

Barrier changes

skin holds water less well

Higher sensitivity

every irritant now leaves a bigger mark

↺ 5 → 1 · THE CYCLE CLOSES

A simplified model, not a fully proven step-by-step sequence. In reality, these factors act at the same time and feed each other.

A surprising finding

It isn’t only the yeast. Dry, leaky skin plays a part too.

Researchers compared two patches of skin on the same person in 37 people: one with a rash and one without. What was different?Exp Dermatol 2024↗︎

Healthy patch

Patch with a rash

Skin holds water

skin barrier function

The “mortar” between cells is intact

ceramide makeup, the fats that hold skin together

Bacteria are in balance

on the rash, more Staphylococcus, less Cutibacterium

Amount of yeast Malassezia

no meaningful difference

The length of the lines shows the direction of the difference, not measured values.

In plain words

There was just as much yeast on the rash as on healthy skin. The difference was in the skin itself: where the rash was, the skin held water less well.

What this means for you

That’s why an antifungal shampoo alone isn’t enough for many people. Your skin also needs help to hold on to water: gentle washing and regular care that protects the surface.

One study with 37 people isn’t final proof. But it’s a good hint, and it matches what we see in real life.

How common it is

You’re not alone, and it’s not “just cosmetic”

Two large analyses pulled together data from more than a hundred studies worldwide. Here are two numbers worth knowing.

How often

4 in 100

people have seborrheic dermatitis. In a class of 25 kids, that’s one.

An estimate of 4.38% from a review of 121 studies with more than 1.26 million people. It varies a lot between countries.2024 meta-analysis↗︎

How much it gets in the way

Moderately

On a quality-of-life questionnaire, people scored 7 out of 30 points on average. At that level, the problem noticeably affects how you feel every day, but not yet every part of your life.

DLQI questionnaire, average 7.2 in 3,812 people.2026 meta-analysis↗︎

So: a common condition that really bothers people. It deserves proper care, not a shrug.

Where it shows up

A map of the areas rich in oil glands

Where it appears isn’t random. It follows the areas with the most oil glands.

scalp and hairline
between the eyebrows and on the eyebrows
creases beside the nose
behind the ears and the outer ear canal
beard and mustache
edges of the eyelids
breastbone and upper back
larger skin folds

You may see white or yellowish flakes, redness, itching and a tight feeling. Dandruff can be a milder, less inflamed part of the same spectrum, but not all dandruff is the same as seborrheic dermatitis.

Telling them apart

What it can be mistaken for

Condition	What can set it apart	Common areas	Read more
Dandruff	Flaking with little or no visible redness.	Scalp	Part of the same spectrum, covered on this page
Seborrheic dermatitis: why it keeps coming back	Redness, itching and greasy or dry flakes.	Scalp, eyebrows, nose, ears, chest	This page
Psoriasis (sebopsoriasis)	Thicker plaques with sharper edges.	Scalp, behind the ears, elbows	More about psoriasis →
Contact dermatitis	Linked to a new product or contact with something.	Where the product was applied or touched the skin	Irritation and allergy from contact →
Atopic dermatitis (eczema)	Very dry skin, strong itching and a different pattern.	Face or skin folds, depending on age	Barrier, inflammation and microbiome →
Tinea (fungal infection)	Ring-shaped patches, breaking hair or hair loss in one spot.	Skin or scalp	Needs a doctor’s opinion

Why it comes back

A flare-up isn’t proof you’re doing something wrong

It helps to separate three things: causes (why someone develops the condition), associated factors (what often shows up alongside it) and flare-up triggers (what ends a calm stretch). The list below belongs to the third group.

colder, dry air

stress and lack of sleep

sweating, hats and helmets

irritating products

scratching and picking at flakes

a change in routine

illness or a demanding time

None of these triggers applies to everyone. That’s exactly why a simple flare-up diary is useful: area, weather, products, stress, itching and time until the flare-up. After a few weeks, your own pattern usually shows up, and that’s more useful than any general list.

What actually helps

Calming a flare-up and keeping it calm aren’t the same job

Active flare-up

Calm the inflammation

When seborrheic dermatitis is confirmed, doctors often recommend antifungal medicines or medicated shampoos, for example with ketoconazole or ciclopirox. With strong inflammation, a doctor may suggest a short course of anti-inflammatory treatment.

Follow the directions for the specific product, or from your pharmacist or doctor, especially for the face, eyelids, children and long-lasting problems. We don’t give doses here.

Maintenance

Make the calm stretch last longer

wash your scalp often enough that oil, flakes and product residue don’t build up
how often isn’t the same for everyone: some people need every day, others twice a week
a medicated shampoo and a regular shampoo don’t do the same job
very hot water, scratching and harsh scrubbing increase irritation
if flare-ups keep coming back, a doctor or pharmacist may suggest using a medicated product for maintenance

Washing less often isn’t automatically gentler, and washing every day isn’t automatically harmful.

What the Cochrane review found

with ketoconazole, the chance that symptoms were still there after four weeks was 31% lower than with a placebo;
in the studies analyzed, ketoconazole worked about as well as topical corticosteroids, but with fewer reported side effects;
ciclopirox led to more clinical improvement than a placebo.Cochrane↗︎

An important limit: the quality of the included studies varied, and many were short and small. So here too, there’s no single recipe that works the same for everyone.

Different areas

Scalp, face and cradle cap need different approaches

Scalp

With a medicated shampoo, what matters is that it reaches your scalp, not just your hair, and that you leave it on as long as the directions say.

We don’t recommend putting a thick layer of greasy ointment over an adult’s whole scalp and leaving it on overnight.

Face and the sides of the nose

Gentle cleansing, no fragrance or irritating actives during a flare-up, and care that’s light enough. Fewer steps are often better here.

The area around the eyes needs extra care and a doctor’s opinion.

Cradle cap in babies

Cradle cap usually runs a different, milder course than chronic seborrheic dermatitis in adults. Gentle washing helps, along with carefully softening the flakes and removing them with a soft brush. No picking.

If there’s spreading redness, oozing, a bad smell, your baby seems unwell, or it keeps spreading, have a pediatrician take a look. More: baby eczema.

Occlusion

Occlusion isn’t the enemy. The wrong timing is.

An occlusive layer can reduce water loss through the skin. That’s why it can help on small, flat, very dry or cracked areas. At the same time, it isn’t antifungal and doesn’t treat the underlying inflammation.

A thick occlusive layer isn’t automatically right for oily, actively inflamed, yellow-flaky or bumpy skin around hair follicles. On those areas, a heavy ointment can feel unpleasant, and for some people it can even make things worse.

Dry, flat and cracked

A thin protective layer can make sense.

Oily, yellow-flaky, inflamed

Proper treatment first, and a lighter routine.

Small bumps or pustules

No heavy occlusion; see a doctor if needed.

The diagnosis isn’t clear

Don’t judge from a photo alone.

Two oversimplifications we won’t repeat: that every oil or ointment “feeds Malassezia,” and that occlusion suits every flare-up. Both are too black-and-white.

Microbiome

Probiotic skin care is interesting. The evidence isn’t as big as the promises yet.

A small 2024 study

25 people took part;
for one week, they used an oil suspension with two selected bacterial strains;
signs of seborrheic dermatitis improved;
the relative share of Malassezia in the sample dropped for a while, then moved back toward the starting level after they stopped;
the study didn’t have a proper control group and was short.Sci Rep 2024↗︎

AT THE START

96,5 %

AFTER USE

74,8 %

LATER

93,0 %

This is the relative share in a microbiological sample, not the absolute number of yeasts on the skin. After they stopped, the value went almost back to where it started.

The results are interesting, but they don’t yet prove that “probiotic cosmetics” can treat seborrheic dermatitis.

Diet

A signal, not a recipe

A 2024 systematic review covered 13 studies and 13,906 participants. They looked at eating patterns, body weight, alcohol, vitamins and minerals. The results were mixed and mostly observational.2024 review↗︎

A link doesn’t prove a cause.

There isn’t enough evidence for a one-size-fits-all “seborrheic dermatitis diet.”

We don’t recommend supplements unless a deficiency has been found.

We don’t encourage restrictive diets. But you can keep track of your own triggers.

When to see a doctor

When to get help

Pain, swelling, oozing, pus or honey-yellow crusts.

Changes on the eyelids or problems with your eyes.

Hair loss or breaking hair in one spot, and sharply outlined patches.

A sudden, very widespread or unusually severe flare-up.

Symptoms that don’t improve even though you’re using the recommended treatment correctly.

A baby whose skin changes are spreading or who seems unwell.

The diagnosis isn’t clear.

Practical questions

What people ask most

Do I have to wash my hair every day?

There’s no one rule for everyone. What matters is that oil, flakes and product residue don’t build up on your scalp. For some people that means every day, for others twice a week. The myth that washing less is always gentler isn’t true, and neither is the idea that washing every day is automatically harmful. What counts is how your skin responds.

Can I use oil on my scalp?

During an active, greasy, inflamed flare-up, a thick layer of oil usually isn’t the best first choice, because it can make things feel and look worse. On small, flat, cracked areas, like behind the ear, a thin protective layer can make sense. But the idea that every oil “feeds” the yeast is an oversimplification.

Does seborrheic dermatitis cause hair loss?

The condition itself usually doesn’t damage hair follicles. During a flare-up you may notice more shedding from inflammation, scratching and pulling off flakes, and that’s mostly temporary. But if you have hair loss in one spot, breaking hair or a lot of hair loss, see a doctor. It can be a sign of a different condition.

Does sun help?

Some people say it calms down in summer, others don’t notice a difference. But sun isn’t a treatment, and it’s no excuse to go without sun protection. For some people, sweat and heat can even set off a flare-up.

Are seborrheic and seborrhoeic dermatitis the same thing?

Yes, it’s the same condition. On this page we use the US spelling seborrheic dermatitis, while the British spelling seborrhoeic dermatitis often shows up in UK and international sources and in searches.

Why does it come back after treatment?

Because it’s chronic, and treatment calms a flare-up without taking away the tendency. Your skin keeps making oil, Malassezia stays part of the normal microbiome, and your inflammatory response doesn’t change. That’s exactly why calming a flare-up and keeping things calm are two separate jobs, and why it coming back isn’t your fault.

Chicatella care

A calm scalp and skin without flaking: every day, not just during treatment

A medicated shampoo calms a flare-up. But what about the days in between? Chicatella takes care of the days between washes: it cleanses gently, locks in moisture and protects your skin to help the calm stretch last longer.

SOS Shampoo – shampoo for a flaky, itchy scalp prone to seborrheic dermatitis

For the scalp · every day

MAIN STEP

SOS Shampoo

Cleanses without drying. Your scalp feels comfortable.

A gentle wash for the days between medicated shampoos. It washes away flakes and product residue and leaves your scalp calm and comfortable, without that tight feeling.

✓Gentle enough for daily washing

✓No fragrance or irritating ingredients

✓Fewer flakes on your shoulders, a more comfortable scalp all day

Meet SOS Shampoo →

For face, chest and back

SOS Body Wash

Clean, but not tight.

Regular body washes strip away the protective layer, and your skin feels tight after a shower. This one cleanses the oily areas on your chest, back and face without drying them out.

✓One product for face and body

✓No fragrance, no stinging

✓Skin stays soft after a shower

Meet SOS Body Wash →

For cracks behind the ears and beside the nose

SOS Ointment

Protects a sore crack overnight.

A thin layer on a cracked crease behind the ear or a dry edge beside the nose. The protective film locks in moisture, so the skin softens and feels less tight.

✓Spot use, very thin, only on dry areas

✓Petrolatum and lanolin, ingredients we trust

✓One tube lasts for months

Meet SOS Ointment →

✓ Free shipping on 2 or more✓ Microbiome-friendly care✓ Fragrance-free

Chicatella is cosmetic skin care. It doesn’t treat seborrheic dermatitis and doesn’t replace antifungal or anti-inflammatory treatment. Don’t apply the ointment to your whole scalp.

Before & after

When supportive care helps flaky, irritated skin

The same skin before and after care. Customer photos, shared with permission.

Browse→

Seborrheic dermatitis on the upper back and neck before and after – small red bumps

Seborrheic dermatitis on the face before and after – red, scaly forehead and eyebrows of a man

Seborrheic dermatitis in babies before and after – red, patchy skin on the forehead

These photos show individual experiences with cosmetic care for flaky or irritated skin. Chicatella isn’t a medicine for seborrheic dermatitis, the photo doesn’t confirm a diagnosis, and individual results may vary.

Tell similar conditions apart

Dermatitis as an umbrella term

Why dermatitis isn’t one single condition.

Read →

Atopic dermatitis (eczema)

Barrier, inflammation and microbiome in one cycle.

Read →

Contact dermatitis

When contact with a specific substance is to blame.

Read →

Eczema on the face

Sensitive spots and care without overload.

Read →

Baby eczema

Cradle cap and care for the littlest ones.

Read →

Psoriasis

Thicker plaques with sharper edges.

Read →

Rosacea

Lasting facial redness and visible blood vessels.

Read →

Dry skin

Why moisturizing isn’t always enough.

Read →

Eczema

How the term connects to dermatitis.

Read →

Help me choose

Find the right care for your skin in three steps

No guesswork. Answer three quick questions and we’ll tell you what your skin needs.

This content is for information only and doesn’t replace a doctor’s exam, diagnosis or treatment. Similar skin conditions can need different care. Chicatella products are cosmetic skin care products, not medicines.

Sources & references

Seborrheic dermatitis isn’t just dandruff. It’s a balance between skin oil, the microbiome and your skin barrier

Start with the short answer

Seborrheic dermatitis has more than one face

Skin can be oily on the surface and still lose water

Be the first to know

It comes from a relationship, not a single cause

It isn’t only the yeast. Dry, leaky skin plays a part too.

You’re not alone, and it’s not “just cosmetic”

A map of the areas rich in oil glands

What it can be mistaken for

A flare-up isn’t proof you’re doing something wrong

Calming a flare-up and keeping it calm aren’t the same job

Scalp, face and cradle cap need different approaches

Occlusion isn’t the enemy. The wrong timing is.

Probiotic skin care is interesting. The evidence isn’t as big as the promises yet.

A signal, not a recipe

When to get help

What people ask most

A calm scalp and skin without flaking: every day, not just during treatment

When supportive care helps flaky, irritated skin

Tell similar conditions apart

Find the right care for your skin in three steps

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