Heredity

One of the biggest causes of cheek acne is heredity. Which is unfortunate, since you can't exactly control who your parents are. That being said, just because your parents had acne, does not mean you will as well. It just means that your likelihood of developing breakouts is increased.

Oily Skin

If you naturally have oily skin, you are much more likely to suffer from acne on your cheeks. And this can be troublesome, especially if it feels like you're already washing your face all the time. Even so, there are treatments that can help modify the oil-content of your skin and bring it more into balance, such as various cleansers and creams. Just don't overdo it. Washing your face too much can actually encourage the production of more oil.

Stress

Stress is another big cause of acne on any part of your body, including the cheeks. Even if you think you have a handle on your stress level, those breakouts might tell a different story. Work to take time for yourself and for relaxing. Your skin will thank you for it.

Hormone Fluctuations

Hormones play a major role in whether you'll suffer from acne. This is why women tend to break out right before or during their periods. However, men can also suffer from hormone-related acne, though this usually subsides by the end of puberty.

Cosmetics

Some cosmetics can actually cause acne or make it worse. Avoid products that contain oils and instead opt for noncomedogenic and hypoallergenic formulations.

Nutrition and Medication

For some people, the lack of certain nutrients can cause acne flare-ups. Failing to drink enough water can place the skin at an imbalance and encourage acne. Likewise, some prescription drugs can make acne worse. Birth control pills have been known to both help and harm when it comes to acne, so your specific prescription may need to be evaluated for effectiveness.