These bacteria produce chemicals and enzymes that can cause inflammation. It's also often referred to as a microcomedo because it cannot be seen by the naked eye. A comedo or lesion that reaches the surface of the skin and opens up is called a blackhead because it looks black on the skin's surface. This black discoloration is not because of dirt. Another factor is heredity or genetics.
Researchers believe that the tendency to develop acne can be inherited from parents.
Stress also appears to aggravate acne. Friction caused by leaning on or rubbing the skin or the pressure from bike helmets, backpacks, or tight collars can contribute to or worsen acne. Chocolate and greasy foods are often blamed for the problem, but research has shown that foods seem to have little effect on the development and course of acne in most people. Additional goals are to reduce the number of painful lesions and to minimize the psychological stress and embarrassment caused by this disease. Most doctors recommend that people with acne gently wash their skin with a mild cleanser, once in the morning and once in the evening.