You can be doing all the right things and following the strictest of all skincare regimens but your skin will decide not to cooperate with you. You’ll still be breaking out.

If you’re in this boat, here are some reasons why you’re still breaking out that you need to address.

Oil based beauty products

Makeup, moisturizing creams, lotions, and hair products that contain pore-clogging sulfates, mineral oil, coconut and cocoa butter, and silicones can encourage the blocking of your skin’s pores. Look for noncomedogenic, oil-free, and unscented cosmetics, toiletries, and sunscreens. Harsh chemicals in laundry detergent can also irritate sensitive skin.

You’re sleeping on a dirty pillowcase

During the day, dirt, oil, makeup, and grime build up on the skin. If you don’t wash your face before you go to sleep, all of that garbage then gets transferred to your pillowcase, which gets transferred back to your face again. Long-term exposure of your skin to this type of soiling, along with the friction of the face rubbing against the pillowcase, may promote inflammation and acne breakouts. But that’s not all! An oily environment may be a breeding ground for bacteria that can infect the skin if there are any raw or open areas—one of the many acne causes.

Water

You know the joke when a bunch of women are pregnant: Must be something in the water. That may actually be true about pimples. Hard water (i.e., with a high concentration of minerals) doesn’t rinse away soap as effectively, and the leftover residue can clog pores.

Sun

Sun, heat and humidity can cause oil glands to become overactive, which can lead to acne breakouts. You need to apply sunscreen and when choosing one, choose an oil-free, non-comedogenic sunscreen.

Hormones

When androgens rise in both boys and girls during puberty, the sebaceous glands under the skin enlarge and produce more sebum, or oil. Too much sebum damages the pore’s cellular walls and allows bacteria to grow. Hormonal changes during menstruation, pregnancy, and the use of oral contraceptives can all affect sebum production and cause acne to develop or recur.

You’re not getting enough sleep

Sleep is a time of rest and repair, and cortisol levels decrease. Not getting enough sleep means that our body is exposed to continuously high levels of cortisol, which can trigger breakouts.

Sleeping in your makeup

Not removing your makeup before bedtime—now that’s a cardinal sin! Makeup left overnight hinders skin renewal and clogs pores. And when your pores are clogged, bacteria build up and cause inflammation. Pollution and grime also build up on makeup throughout the day. The layers of dirt and bacteria, which are mixed with the oil on your skin, can occlude pores and lead to acne.

Which of these describes you?