Decoding Sebum: Why Skin Oil Isn’t Necessarily a Bad Thing
Sebum. Just the words sounds kind of gross. What is this substance we’re constantly in battle with? The oil control patrol is out in full force, with blotting papers, oil-free moisturizers, mattifying foundations, and more in the standard skincare and beauty arsenal. The odds are stacked against sebum on the shelves of Sephora. But why? Let’s get the full story.
What is sebum?
Produced by the sebaceous glands in the skin, sebum is a waxy, oily substance needed to keep skin moisturized. It creates a barrier that both holds moisture in and protects the skin from bacterial and fungal infections.
It’s more complicated than just being oil. Sebum is a combination of triglycerides, free fatty acids, wax esters, squalene, cholesterol esters, and cholesterol. As it’s secreted through hair follicles or pores, it also picks up lipids from skin cells and sweat. Plus, it mixes with environmental material on the surface of the skin. (1)
Yes, there’s a whole lot of stuff all over your face right now, but you want it there! Beyond sebum being necessary for basic skin health, people with lots of oil tend to have thicker skin and less wrinkles because of the moisturizing and protective properties of sebum.
Why does oil cause acne?
Unfortunately, sebum is also one of the main culprits behind acne. When sebum, dead skin cells, and dirt become trapped inside pores, it can lead to a pimple. The likelihood of this is exacerbated when sebum is in excess.
The back, forehead, and chin have the most sebaceous glands (a whopping 400–900 per square centimeter!) and are also areas commonly populated by acne. Plus, sebaceous glands have receptors influenced by hormones, primarily androgens, and this is why oil production picks up during puberty and at certain points in the menstrual cycle to the effect of causing acne. (2, 3)
Balancing skin oil
Too much sebum leads to oily skin, and too little sebum leads to dry skin. Confusingly, even dry skin can present as oily as it overcompensates for a lack of moisture by producing more oil. Oh, and remember there's a difference between dry and dehydrated skin.
Oily and dry are considered “skin types” and treated as permanent states of being. But as hinted at above, the levels of sebum production can and do change—more like skin moods. When considering skin moment to moment, finding balance when it comes to skin oil is key. Though, that’s much easier said than done. Ideally, skin has enough oil to stay moisturized and protected but not so much that pores get clogged.
Surprisingly, adding a facial oil to your routine can work for both sides of the oily/dry spectrum. The right facial oil can help regulate oil production, both making up for a lack in drier skin and signaling to oilier skin that it doesn’t need to keep producing so much.
When you next have the inevitable urge to powder or blot away that midday forehead shine, consider the source. Sebum still isn’t the most enticing thing to think about, but understanding why your skin is producing so much or so little unlocks the real potential to address it.