Pimples that pop up long past the teenage years are just, well ... unfair.
"Hormonal changes and using the wrong skin care products are common causes," says Dr Melissa Schwarzschild, a dermatologist with Richmond Dermatology & Laser Specialists in the US.
But you can fight back:
* Wash your face every night: Oil, dirt and sweat build up in skin pores and can lead to pimples. That's true for women - especially those who wear make-up - and men, who naturally produce more oil. Also aim to shower soon after exercise.
* Exfoliate regularly: Remove dead skin cells at the skin's outermost surface once or twice a week. Use a low strength glycolic acid or mild facial scrub.