Your makeup

Even if your makeup is labelled non-comedogenic, it could still be breaking you out. While some people are sensitive to certain ingredients, Dr. Lamees Hamdan, founder and CEO of skin care brand Shiffa [2], said you should only try new ingredients one at a time. Once you start to figure out which products are causing your acne, you can look at ingredients labels and try to find a pattern.

Your pillows

When's the last time you changed your pillowcase? If it's been a while, that might be the source of the breakout on your cheek, especially if you sleep on your side. We all sweat a little in our sleep, creating a moist environment for bacteria to grow. Make sure to swap your pillowcases regular to prevent breakouts.

Your cell phone

According to a study at Arizona State University [3], your cell phone contains up to 10 times the amount of bacteria as a toilet seat. If you're constantly talking on the phone, or even texting and then touching your face, you're transmitting a lot of bacteria onto your skin and potentially causing some zits. It might be time to invest in a phone sanitizer.

Your diet

You may have heard that junk food can make you break out, but it's not that simple. Different foods make different individuals break out and there are a variety of food groups that might be breaking you out. "Too much sugar and white carbs can be a problem," Dr. Hamdam said. "Diary can also be a causing factor."

Your hair products

While you're in the shower, make sure to wash your face with cleanser after shampooing your hair. Any leftover shampoo or conditioner residue can lead to breakouts. If you're breaking out around your hairline, consider the styling products you're using and make sure not to spray them too close to your face.

Your birth control

Dr. Hamdan explains that while some birth control can help get rid of acne, some can make it worse. "Generally speaking, birth control helps alleviate acne for the majority of women," he said. "However, androgenic pills — meaning those that contain testosterone or androsterone — can actually promote acne."

There's good news, though. If you're using a pill that contains both progesterone and estrogen, it can actually decrease the severity and frequency of your pimples. "These pills help decrease the amount of androgen (the male sex hormones) in the body. The less androgens, the less sebum is produced by the body. The less sebum produced, the less chance of it combining with bacteria and dead cells from the skin and causing a pimple," Dr. Hamdan said.