Dear Dr. Universe
Why do you get acne?
— Joey, Illinois
Whether we call them pimples, spots or zits, acne is something most people experience. As many as 95% of people have some acne sometime. That’s nearly everybody.
I talked about acne with my friend Sarah Fincham. She has a clinical doctorate in nursing. She’s a nurse and a professor in the College of Nursing at Washington State University.
If you look at your skin, you’ll see tiny openings called pores. These pores connect to oil-producing glands under our skin. They’re called sebaceous glands, and the oil they make is called sebum.
“Sebum does good things,” Fincham said. “It keeps the skin soft because the oil prevents moisture loss. It keeps the hair from becoming too brittle and breaking. It even contains some antibacterial chemicals. It’s supposed to help keep our skin healthy.”
Another way skin stays healthy is by shedding old cells. We shed millions of skin cells every day.
During puberty, our bodies produce lots of chemical messengers called hormones. These zoom around telling our cells what changes need to happen to transition from a kid body to an adult body. Some hormones also tell the body to crank up sebum production.
That extra oil mixes with the old skin cells as they shed. They can become sticky and clog the pores. A partly clogged pore is called a blackhead. A completely clogged pore can cause a tiny skin infection that makes a red bump. This infection sometimes makes a whitehead. Sometimes it makes a tender swollen bump under the surface of the skin.
That’s because there are bacteria that live on our skin and in our pores. They eat sebum. Normally, our relationship with these bacteria is commensal. That means they don’t help us or hurt us. They just hang out and gobble up oil.
But when there are too many of them — like inside a clogged pore — our immune systems send white blood cells to fight the bacteria and keep them in check. That immune response causes inflammation. That’s why acne can be red or look swollen.
There are lots of things we don’t know about acne. Like, why do some people get mild acne while others have more?
We do know that nothing we do causes acne. It can’t make us sick. It’s just a thing that happens — to nearly everybody.
Acne can show up anywhere except the palms of our hands and soles of our feet. That’s because we don’t have oil-producing glands there.
A healthcare provider like Fincham can prescribe medicine to help clear up acne.
“There are lots of products and medicines that truly are awesome treatments for acne,” she said. “They are mostly prescription based, so you’d have to see a health care provider. But there are so many good treatments that are safe to use.”
Other than that, Fincham recommends using a gentle skin cleanser, avoiding products that seem to clog your pores and trying not to pick at it.
Even though acne is super common and affects nearly everyone at some point, it bothers some people more than others. Your feelings matter. If you’re concerned about acne or any other part of puberty, talk to a grownup you trust.
Have a science question? Ask Dr. Wendy Sue Universe, WSU’s resident science cat and writer, by email at Dr.Universe@wsu.edu, on her website at askDrUniverse.wsu.edu, via Twitter at @AskDrUniverse or at facebook.com/AskDrUniverse.