Causes of Acne

• Hormonal activity, such as menstrual cycles and puberty
• Stress, through increased output of hormones from the adrenal (stress) glands.
• Hyperactive sebaceous glands, secondary to the three hormone sources above.
• Diet ^{[citation needed]}
• Accumulation of dead skin cells.
• Bacteria in the pores, to which the body becomes 'allergic'.
• Skin irritation or scratching of any sort will activate inflammation.
• Use of anabolic steroids.
• Any medication containing halogens (iodides, chlorides, bromides), lithium, barbiturates, or androgens.
• Exposure to high levels of chlorine compounds, particularly chlorinated dioxins, can cause severe, long-lasting acne, known as Chloracne.

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