BACKGROUND: Acne vulgaris is one of the main reasons for dermatological 
consultations. Severity and response to treatment may be impacted by various 
external factors or exposome.
AIM: To assess the impact of environmental factors on acne and to provide a 
comprehensive overview of the acne exposome.
METHODS: Two consensus meetings of five European dermatologists and a 
comprehensive literature search on exposome factors triggering acne served as a 
basis for this review.
RESULTS: Acne exposome was defined as the sum of all environmental factors 
influencing the occurrence, duration and severity of acne. Exposome factors 
impact on the response and the frequency of relapse to treatments by interacting 
with the skin barrier, sebaceous gland, innate immunity and cutaneous 
microbiota. They may be classified into the following six main categories: 
nutrition, psychological and lifestyle factors, occupational factors including 
cosmetics, as well as pollutants, medication and climatic factors. Moreover, 
practical considerations for the dermatologist's clinical practice are proposed.
CONCLUSION: Exposome factors including nutrition, medication, occupational 
factors, pollutants, climatic factors, and psychosocial and lifestyle factors 
may impact on the course and severity of acne and on treatment efficacy. 
Identifying and reducing the impact of exposome is important for an adequate 
acne disease management.