Acne affects approximately 650 million people (9.4% of the population) around the globe and ranks among the eight most widespread diseases worldwide. 1,2  The cause of acne is multifactorial, involving hormone imbalance, the body’s own immunity and genetics. 3

The classic view on acne puts excessive oil production from the oil glands in the skin as the starting point of acne, followed by skin thickening, bacterial multiplication, and inflammation.

Recently, acne has been identified as an inflammatory disease, with microinflammation being the root cause that starts the acne cycle. 4,5 Acne is a member of the six chronic diseases (insulin resistance, diabetes, obesity, cancer, increased body mass index, and acne) that are associated with an over-activation of the regulator that controls nutrient/energy/redox sensor and protein synthesis in the human body (mTORC1 protein complex). 6 


  1. Rocha, M. A.; Bagatin, E., Adult-onset acne: prevalence, impact, and management challenges. Clin Cosmet Investig Dermatol 2018, 11, 59-69.
  2. Vos, T. et. al. Years lived with disability (YLDs) for 1160 sequelae of 289 diseases and injuries 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012, 380 (9859), 2163-2196.
  3. Dréno, B. et. al., Nonprescription acne vulgaris treatments: Their role in our treatment armamentarium—An international panel discussion. Journal of Cosmetic Dermatology 2020, 19 (9), 2201-2211.
  4. Dréno, B., What is new in the pathophysiology of acne, an overview. J Eur Acad Dermatol Venereol 2017, 31 Suppl 5, 8-12.
  5. Dreno, B.;  Pecastaings, S.;  Corvec, S.;  Veraldi, S.;  Khammari, A.; Roques, C., Cutibacterium acnes (Propionibacterium acnes) and acne vulgaris: a brief look at the latest updates. Journal of the European Academy of Dermatology and Venereology 2018, 32, 5-14.
  6. Melnik, B. C., Acne vulgaris: The metabolic syndrome of the pilosebaceous follicle. Clinics in Dermatology 2018, 36 (1), 29-40.

Sciences of Acne