Blackheads vs sebaceous filaments: are those dots on your nose really blackheads?

What are sebaceous filaments?

Cleveland Clinic describes sebaceous filaments as thin, thread-like structures that line the oil glands and help carry sebum (skin oil) up to the surface. A dermatology case report in Dermatology Practical & Conceptual describes them as yellowish to off-white collections of sebum and dead cells around hair follicles.

The key point: everyone has them, and they’re healthy. They’re not acne and they don’t need “clearing”. They just become more visible when the pore is large or the skin is oily.

What’s the difference between a blackhead and a sebaceous filament?

	Sebaceous filament	Blackhead (open comedone)
What it is	Normal oil channel lining the pore	A pore blocked by a plug of oil and dead skin
Is it acne?	No	Yes, mild (comedonal) acne
Colour	Grey, light brown, tan or yellowish	Dark brown to black
Shape	Flat, flush with the skin	Often slightly raised
Pattern	Many, evenly spaced, same size	Fewer, scattered, uneven sizes
If squeezed	A thin, waxy, thread-like strand (or nothing)	A dark-topped waxy plug
After removal	Refills within about 30 days	Can come back if pores keep clogging
Where	Nose, forehead, chin, cheeks	Nose, forehead, chin; also back and chest

Sources: Cleveland Clinic, DermNet, NHS.

Why are blackheads black?

Not because of dirt. The NHS explains that the colour comes from pigment produced by the lining of the hair follicle, and DermNet attributes it to surface melanin. That’s why the American Academy of Dermatology (AAD) advises against scrubbing: it won’t remove the colour and can make acne worse.

A quick self-check

1. Look from normal distance, not a magnifying mirror. If the dots disappear at arm’s length and look evenly spread, they’re very likely filaments.
2. Check the colour. Grey, tan or yellowish points to filaments. A clearly black dot that stands out from its neighbours points to a blackhead.
3. Feel the skin. Filaments are flat. Blackheads can feel slightly bumpy.
4. Look elsewhere. Blackheads alongside whiteheads or pimples on the forehead or chin suggest comedonal acne.

Skin Realist check: the “gunk” that comes out of a nose pore when you squeeze it is usually a filament, not a blackhead. Getting it out doesn’t mean you’ve fixed anything. It will be back within weeks.

Do pore strips work?

Pore strips do pull out the top of what’s sitting in your pores, which is why the strip looks satisfying afterwards. But that’s usually mostly filament material. Cleveland Clinic notes that strips can remove sebaceous filaments as well as blackheads, that filaments refill within about 30 days, and that removing them can dry the skin and let in bacteria.

So:

• They don’t prevent anything. Nothing about a strip stops a pore from refilling or clogging again.
• They don’t shrink pores in any lasting way.
• They can irritate, especially if your skin is sensitive, sunburned, or you’re using a retinoid or exfoliating acid.

If you like using them occasionally, follow the pack directions, don’t use them on irritated skin, and don’t expect a lasting result.

Should you squeeze sebaceous filaments or blackheads?

No. Cleveland Clinic points out that your nails are much harder than your skin and squeezing can irritate or seriously damage it. The AAD warns that squeezing blemishes at home often pushes material deeper into the skin, which increases inflammation and can cause scars, more noticeable acne and infection.

If you have stubborn blackheads, a dermatologist can do comedo extraction with sterile instruments. The AAD notes it’s usually offered only when other treatment hasn’t worked, and blackheads can return afterwards, so you’ll still need a routine to prevent new ones.

How to make sebaceous filaments less visible

You can’t remove filaments for good, but Cleveland Clinic lists ways to make them smaller and less noticeable:

• Salicylic acid (a BHA), as a cleanser or leave-on product. It helps clear dead skin cells so follicles are less likely to clog. CeraVe Renewing SA Cleanser is a fragrance-free wash, and COSRX BHA Blackhead Power Liquid is a leave-on using betaine salicylate, a related ingredient.
• A retinoid, such as over-the-counter adapalene or a retinol product. Retinoids help prevent clogged pores. Peeling and redness are common at first; using it every other night or with a moisturiser helps.
• Gentle, regular cleansing once or twice a day with a mild cleanser and lukewarm water.
• Moisturiser. Cleveland Clinic notes that over-drying the skin (too much washing, too much sun) can make oil glands work harder and filaments look bigger.
• Non-comedogenic products, and removing makeup every night.

Clay masks (for example kaolin, or the bentonite in Perricone MD Acne Relief Clay Mask) can soak up surface oil for a few hours, which may make filaments look less obvious for a short time. We couldn’t find good evidence that they change filaments or blackheads long-term.

If filaments still bother you after a couple of months of this, Cleveland Clinic suggests seeing a doctor, who can prescribe stronger treatments that reduce oil production.

How to treat real blackheads

Because blackheads and filaments are made of the same material (oil and dead skin), the treatments overlap. For true blackheads, the AAD recommends:

• A retinoid to unclog pores. Adapalene is available without a prescription in the US.
• A benzoyl peroxide wash, especially if you also get pimples.
• Six to eight weeks of consistent use before judging the result.

The full routine is in how to clear blackheads.

When should you see a dermatologist?

• Blackheads haven’t improved after six to eight weeks of a retinoid or salicylic acid.
• You have lots of whiteheads, pimples or deeper spots as well.
• Squeezing has left marks or scars.
• You’re not sure what the bumps are. Some forehead bumps that look like clogged pores are actually fungal acne or keratosis pilaris.