How does stress cause acne?

Stress causes acne as per the number of studies. Acne is purely a physical condition and it is affected or aggravated by a psychological factor stress. This shows how our mind body are closely linked. Stress triggers adrenal glands to produce certain hormones which is responsible for stimulating the sebaceous glands which produces sebum. Sebum is an oily substance that is produced by the body to lubricate our skin but when this oily substance is blocked inside the pores of the skin it reacts with the harmless bacteria that resides inside the skin and the mixture of sebum and bacteria form acne. So when we are stressed excessive sebum is secreted which increases the chances of getting acne. Moreover when we are stressed our immunity level comes down and the acne lesions do not heal because of this. Thus stress aggravates acne.