Beneath the skin’s surface lie tiny glands that create sebum, an oily substance that helps lubricate the skin. Sebaceous filaments are structures that allow sebum to flow to the surface of the skin.
When the body overproduces sebum, the sebaceous filaments can fill up. They may become visible and resemble very enlarged pores.
People often confuse sebaceous filaments with blackheads. Blackheads are a form of acne.
Sebaceous filaments are not a type of acne, they are normal structures within the skin.
However, the overproduction of sebum that causes sebaceous filaments to fill up and become noticeable can also cause whiteheads or blackheads.
In this article, we look at how sebaceous filaments become visible. We also describe the differences between sebaceous filaments and blackheads, treatments for each, and when it might be a good idea to consult a doctor.
When sebaceous filaments are noticeable, they can look like enlarged, darkened pores. A person might easily confuse them for blackheads.
The key differences between blackheads and sebaceous filaments involve their:
A blackhead is a blockage or plug at the top of a pore. The plug prevents oil from escaping through the pore.
A sebaceous filament is a thin, hair-like structure that lines the inside of the pore and helps sebum travel to the skin’s surface. It has no plug.
Appearance and color
A noticeable sebaceous filament may look like a dark dot on the skin. The dot may resemble the head of a pin, and it may be yellow, gray, or clear.
A blackhead is a very dark plug at the top of a pore. The dark color develops when the plug is oxidized through contact with the air.
If a person squeezes, or “extracts,” a sebaceous filament, a white or yellow worm-like structure may ooze out. Or, the filament may not produce anything.
Trying to extract sebaceous filaments can injure the skin and cause scarring. It can also damage and stretch the pore, making it appear bigger.
When a person extracts a blackhead, the dark plug may come off. Beneath it, there may be white or yellow sebum and skin cells.
The American Academy of Dermatology advise against squeezing or popping acne of any kind.
The skin’s normal process of producing sebum can cause sebaceous filaments to become noticeable.
This is more likely to occur in people with more oily skin or larger pores, compared with people who have drier skin and smaller pores.
Several factors can determine pore size, including:
- having thicker hair follicles
- sun exposure
Visible sebaceous filaments are not a sign that the skin is dirty.
Controlling the amount of oil on the skin and using exfoliating skin care products can help keep the pores clear. This may minimize the appearance of sebaceous filaments.
Use gentle products that cleanse the skin to prevent overdrying and irritation. The best product will depend on the person’s skin type.
No skin care product can completely get rid of noticeable sebaceous filaments. However, the following ingredients and approaches can help reduce their appearance:
Salicylic acid, also known as beta hydroxy acid, is an ingredient in many facial cleansers and acne creams. These products may contain 0.5% to 2.0% percent salicylic acid.
This type of acid may help reduce the amount of oil on the skin and the size of sebaceous filaments. Salicylic acid is oil-soluble, which means that it can penetrate sebum and help clear pores.
If a person has not used a product with salicylic acid before, it may be a good idea to start with one application every day or every other day. If dryness or peeling occurs, use the product less often.
Dermatologists can apply salicylic acid peels that are stronger than over-the-counter products. These peels may provide a more dramatic difference in pore size and appearance. They contain 15–50% salicylic acid.
Salicylic acid is a derivative of aspirin, so anyone who is allergic to aspirin should not use it.
Benzoyl peroxide is a common ingredient in acne products. It can help dry the skin and limit the amount of oil, and it may reduce the size of pores.
Benzoyl peroxide can cause excessive dryness and peeling, however, especially at higher concentrations. Anyone who experiences this should use products containing benzoyl peroxide less frequently. Or, switch to products with lower concentrations of the ingredient.
Tea tree oil
It can, however, cause irritation and allergic reactions. Tea tree oil has the most reported allergic reactions of any essential oil.
Anyone who is applying tea tree oil directly to the skin should dilute it to a strength of 5%.
Seek immediate medical care if signs of an allergic reaction occur, such as hives, swelling, or trouble breathing.
A 2015 study suggests that long-term sun exposure can make the pores larger, which may lead to more noticeable sebaceous filaments. Sun exposure also increases the risk of skin damage and skin cancer.
Using sunscreen every day can help minimize the adverse effects of exposure and help keep the skin healthy.
People with oily skin and large pores may prefer to use sunscreen that is oil-free and noncomedogenic, meaning that it does not clog pores. Using greasy or heavy sunscreen could make large pores more noticeable.
Also, it is a good idea to wear a protective hat and clothing that covers the skin when spending extended periods in the sun.
The AAD say it is important to strike the right balance between having too much oil on the skin and maintaining the skin’s natural moisture.
It offers the following tips for controlling oily skin:
- wash the face every morning, evening, and after exercise
- avoid scrubbing, which will irritate the skin and can make it look worse
- use skincare products, such as cleansers, moisturizers, and make-up, labeled “oil-free” or “non-comedogenic,” which are less likely to clog pores
- moisturize every day to keep the skin hydrated
- opt for a gentle, foaming face wash, as harsh products dry out the skin prompting it to produce more oil
- avoid oil- or alcohol-based cleansers as these can irritate the skin
In extremely rare cases, some people can develop sebaceous gland carcinoma.
This rare type of cancer can occur anywhere on the body, including the head, neck, trunk, or genitals but tends to appear on the upper eyelid or around the eye.
The carcinomas look like firm, yellowish lumps, and they do not hurt. The condition is more common in older people and those who have had previous radiotherapy on the face.
Doctors will usually use surgery to remove the lumps. People may also need radiotherapy.
If over-the-counter products and a good skin care routine are not giving satisfactory results, a person may wish to see a dermatologist.
Dermatologists can prescribe more powerful medications for reducing oil production, leading to fewer noticeable sebaceous filaments.
Unlike blackheads and whiteheads, sebaceous filaments do not block pores.
Sebaceous glands are oil-producing glands in the skin. This oil, called sebum, travels to the outer layer of skin, or the epidermis, through the hair follicles. Sebum keeps the skin moist and healthy.
The resulting hair-like cylinders of a yellowish substance are harmless, though many people do not like the way they look.
By controlling oily skin, people can prevent or reduce the occurrence of sebaceous glands.