title: Variation of biophysical parameters of the skin with age, gender, and body region.
abstract: BACKGROUND
  Understanding the physiological, chemical, and biophysical characteristics of the skin helps us to arrange a proper approach to the management of skin diseases.
  
  
  OBJECTIVE
  The aim of this study was to measure 6 biophysical characteristics of normal skin (sebum content, hydration, transepidermal water loss (TEWL), erythema index, melanin index, and elasticity) in a normal population and assess the effect of sex, age, and body location on them.
  
  
  METHODS
  Fifty healthy volunteers in 5 age groups (5 males and females in each) were enrolled in this study. A multifunctional skin physiology monitor (Courage & Khazaka electronic GmbH, Germany) was used to measure skin sebum content, hydration, TEWL, erythema index, melanin index, and elasticity in 8 different locations of the body.
  
  
  RESULTS
  There were significant differences between the hydration, melanin index, and elasticity of different age groups. Regarding the locations, forehead had the highest melanin index, where as palm had the lowest value. The mean values of erythema index and melanin index and TEWL were significantly higher in males and anatomic location was a significant independent factor for all of 6 measured parameters.
  
  
  CONCLUSIONS
  Several biophysical properties of the skin vary among different gender, age groups, and body locations.
authors.affiliation: Center for Research and Training in Skin Diseases and Leprosy, Tehran University of Medical Sciences, 415 Taleghani Avenue, Tehran 14166 13675, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Firooz
authors.forename: Bardia
authors.initials: B
authors.lastname: Sadr
authors.forename: Shahab
authors.initials: S
authors.lastname: Babakoohi
authors.forename: Maryam
authors.initials: M
authors.lastname: Sarraf-Yazdy
authors.forename: Ferial
authors.initials: F
authors.lastname: Fanian
authors.forename: Ali
authors.initials: A
authors.lastname: Kazerouni-Timsar
authors.forename: Mansour
authors.initials: M
authors.lastname: Nassiri-Kashani
authors.forename: Mohammad Mehdi
authors.initials: MM
authors.lastname: Naghizadeh
authors.forename: Yahya
authors.initials: Y
authors.lastname: Dowlati
mesh_terms: D000293:Adolescent; D000328:Adult; D001703:Biophysics; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012879:Skin Physiological Phenomena; D055815:Young Adult