Natural skin surface pH is on average below 5, which is beneficial for its resident flora

@article{Lambers2006NaturalSS,
  title={Natural skin surface pH is on average below 5, which is beneficial for its resident flora},
  author={Hans Lambers and Sofie Piessens and Anna Bloem and H Pronk and Peter Finkel},
  journal={International Journal of Cosmetic Science},
  year={2006},
  volume={28}
}
Variable skin pH values are being reported in literature, all in the acidic range but with a broad range from pH 4.0 to 7.0. In a multicentre study (N = 330), we have assessed the skin surface pH of the volar forearm before and after refraining from showering and cosmetic product application for 24 h. The average pH dropped from 5.12 ± 0.56 to 4.93 ± 0.45. On the basis of this pH drop, it is estimated that the ‘natural’ skin surface pH is on average 4.7, i.e. below 5. This is in line with… 

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