1. Stress causes acne Stress has a minimal influence on a persons ability to develop acne through stress. Stress doesn't cause acne, but it can influence re-occurrence of acne as stress levels increase body's creation of a substance called cortisol. Cortisol causes sebaceous glands in skin to produce increased amounts of sebum oil which ultimately blocks pores. 2. Acne is contagious No one can "catch" acne; it is non-communicable.
3.You'll outgrow acne, so just leave it along and it will heal itself. Acne strikes all ages and is treatable, but shouldn't be left alone to worsen. (It should be treated so it doesn't cause scarring)
4. Being out in sun helps acne The sun may appear to help clear up blemishes and redden skin, thus lessening overall effect. However, rays from sun cause skin damage and irritate and worsen existing acne problems clogging more pores as skin cells dry up and slough off quicker than normal. So use caution (and sunscreen).
5. Sweating helps clean out your hair follicle areas Strenuous activity can temporarily increase your body's oil production which can worsen acne problem areas, causing recurrence or intensification.
6. Acne problems are directly proportionate to sexual activity, (Too much or not enough depending on your point of view) Just because teenagers are going through hormonal changes, doesn't mean it has anything to do with acne. Both are separate issues. Same with adult acne and sex; (These are also two entirely different issues.)