The physiological skin surface pH is just below 5. With age the skin surface pH increases up to 6. An increased pH correlates with reduced barrier integrity/cohesion. The present pilot study assesses possible normalization of an increased skin surface pH of the elderly and improvement of barrier function via application of ≈pH 4.0 skin care products. Baseline skin surface pH was determined in elderly (80+ years old; n = 15) compared to middle aged adults (31 - 50 years old; n = 15). The effect of o/w emulsions at pH-values of 3.5, 4.0, 4.5 and 5.5 on the skin surface pH was determined in both groups. Further, the effect of a 4-week treatment with a pH 4.0 skin care product on the skin surface pH, skin hydration and barrier integrity was assessed. Thirteen elderly females were involved in this home-in-use test. Increased baseline skin surface pH of the elderly normalizes to the physiological pH of 4.5 - 5.0 over 7 hours after single application of o/w-emulsions with a given pH of 3.5 or 4.0. A 4 week treatment employing the pH 4.0 skin care product improves the epidermal barrier integrity of the elderly significantly (p = 0.005). Reduction of the increased baseline skin surface pH of the elderly is accompanied by improved epidermal barrier integrity. Skin care products for the elderly have to be adjusted in the pH range of 3.5 to 4.0.
KeywordsSkin AgingSkin CareSkin Surface pHEpidermal Barrier Function
O. B. Falco and H. C. Korting, “Der Normale pH-Wert der Menschlichen Haut,” Der Hautarzt, Vol. 37, No. 3, 1986, pp. 126-129.
H. Lambers, S. Piessens, A. Bloem, H. Pronk and P. Finkel, “Natural Skin Surface pH is on Average below 5, which is Beneficial for Its Resident Flora,” International Journal of Cosmetic Science, Vol. 28, No. 5, 2006, pp. 359-370. doi:10.1111/j.1467-2494.2006.00344.x
D. Segger, U. A?mus, M. Brock, J. Erasmy, P. Finkel, A. Fitz-ner, H. Heuss, U. Kortemeier, S. Munke, T. Rheinl?nder, H. Schmidt-Lewerkühne, W. Schneider and G. Weser, “Multicenter Study on Measurement of the Natural pH of the Skin Surface,” IFSCC Magazine, Vol. 10, No. 2, 2007, pp. 107-110.
H. Schade and A. Marchionini, “Der S?uremantel der Haut (nach Gaskettenmessung),” Klinische Wochenschrift, Vol. 7, No. 1, 1928, pp. 12-14. doi:10.1007/BF01711684
H. ?hman and A. Vahlquist, “In Vivo Studies Concerning a pH Gradient in Human Stratum Corneum and Upper Epidermis,” Acta Dermato-Venereologica, Vol. 74, No. 5, 1994, pp. 375-379.
P. M. Elias, “Stratum Corneum Defensive Functions: An Inte-grated View,” Journal of Investigative Dermatology, Vol. 125, No. 2, 2005, pp. 183-200.
K. T. Holland, W. J. Cunliffe and C. D. Roberts, “The Role of Bacteria in Acne Vulgaris: A New Approach,” Clinical and Experimental Dermatology, Vol. 3, No. 3, 1978, pp. 253-257.
H. C. Korting, “Das S?uremantelkonzept von Marchioni und die Beeinflussung der Resident-Flora der Haut durch Waschungen in Abh?ngigkeit vom pH-Wert,” In: O. Braun-Falco and H. C. Korting, Ed., Hautreinigung mit Syndets, Springer Verlag, Berlin, 1990, pp. 93-103.
H. Kurabayashi, K. Tamura, I. Machida and K. Kubota, “Inhi-biting Bacteria and Skin pH in Hemiplegia: Effects of Washing Hands with Acidic Mineral Water,” American Journal of Phys-ical Medicine and Rehabilitation, Vol. 81, No. 1, 2002, pp. 40-46. doi:10.1097/00002060-200201000-00007
H. C. Korting, A. Lukacs, N. Vogt, J. Urban, W. Ehret and G. Ruckdeschel, “Influence of the pH-Value on the Growth of Staphylococcus epidermidis, Staphylococcus aureus and Pro-pionibacterium acnes in Continuous Culture,” Zentrallblatt für Hygiene und Umweltmedizin, Vol. 193, No. 1, 1992, pp. 78-90.
T. Mauro, W. M. Holleran, S. Grayson, W. N. Gao, M. Q. Man, E. Kriehuber, M. Behne, K. R. Feingold and P. M. Elias, “Barrier Recovery is Impeded at Neutral pH, Independent of Ionic Effects: Implications for Extracellular Lipid Processing,” Archives of Dermatological Research, Vol. 290, No. 4, 1998, pp. 215-222. doi:10.1007/s004030050293
J. P. Hachem, D. Cumrine, J. Fluhr, B. E. Brown, K. R. Fein-gold and P. M. Elias, “pH Directly Regulates Epidermal Per-meability Homeostasis, and Stratum Corneum Integri-ty/Cohesion,” Journal of Investigative Dermatology, Vol. 121, No. 2, 2003, pp. 345-353. doi:10.1046/j.1523-1747.2003.12365.x
W. M. Holleran, Y. Takagi, G. Imokawa, S. Jackson, J. M. Lee and P. M. Elias, “Beta-Glucocerebrosidase Activity in Murine Epidermis: Characterization and Localization in Relation to Differentiation,” Journal of Lipid Research, Vol. 33, No. 8, 1992, pp. 1201-1209.
J. M. Jensen, S. Schutze, M. Forl, M. Kronke and E. Proksch, “Roles for Tumor Necrosis Factor Receptor p55 and Sphingo-myelinase in Repairing the Cutaneous Permeability Barrier,” Journal of Clinical Investigation, Vol. 104, No. 12, 1999, pp. 1761-1770. doi:10.1172/JCI5307
M. Schmuth, M. Q. Man, F. Weber, W. Gao, K. R. Feingold, P. Fritsch, P. M. Elias and W. M. Holleran, “Permeability Barrier Disorder in Niemann-Pick Disease: Sphingomyelin-Ceramide Processing Required for Normal Barrier Homeostasis,” Journal of Investigative Dermatology, Vol. 115, No. 3, 2000, pp. 459-466. doi:10.1046/j.1523-1747.2000.00081.x
Y. Takagi, E. Kriehuber, G. Imokawa, P. M. Elias and W. M. Holleran, “Beta-Glucocerebrosidase Activity in Mammalian Stratum Corneum,” Journal of Lipid Research, Vol. 40, No. 5, 1999, pp. 861-869.
P. Ovaere, S. Lippens, P. Vandenabeele and W. Declercq, “The Emerging roles of Serine Protease Cascades in the Epidermis,” Trends in Biochemical Science, Vol. 34, No. 9, 2009, pp. 453-463. doi:10.1016/j.tibs.2009.08.001
M. Brattsand and T. Egelrud, “Purification, Molecular Cloning, and Expression of a Human Stratum Corneum Trypsin-Like Serine Protease with Possible Function in Desquamation,” The Journal of Biological Chemistry, Vol. 274, No. 42, 1999, pp. 30033-30040. doi:10.1074/jbc.274.42.30033
E. Ekholm and T. Egelrud, “Expression of Stratum Corneum Chymotryptic Enzyme in Relation to Other Markers of Epi-dermal Differentiation in a Skin Explant Model,” Experimental Dermatology, Vol. 9, No. 1, 2000, pp. 65-70. doi:10.1034/j.1600-0625.2000.009001065.x
C. Caubet, N. Jonca, M. Brattsand, M. Guerrin, D. Bernard, R. Schmidt, T. Egelrud, M. Simon and G. Serre, “Degradation of Corneodesmosome Proteins by Two Serine Proteases of the Kallikrein Family, SCTE/KLK5/hK5 and SCCE/KLK7/hK7,” Journal of Investigative Dermatology, Vol. 122, No. 5, 2004, pp. 1235-1244. doi:10.1111/j.0022-202X.2004.22512.x
A. Zlotogorski, “Distribution of Skin Surface pH on the Fore-head and Cheek of Adults,” Archives of Dermatological Re-search, Vol. 279, No. 6, 1987, pp. 398-401. doi:10.1007/BF00412626
P. Thune, T. Nilsen, I. K. Hanstad, T. Gustavsen and H. Lovig Dahl, “The Water Barrier Function of the Skin in Relation to the Water Content of Stratum Corneum, pH and Skin Lipids. The Effect of Alkaline Soap and Syndet on Dry Skin in Elderly, Non-atopic Patients,” Acta Dermato-Venereologica, Vol. 68, No. 4, 1988, pp. 277-283.
K. P. Wilhelm, A. B. Cua and H. I. Maibach, “Skin Aging. Effect on Transepidermal Water Loss, Stratum Corneum Hy-dration, Skin Surface pH, and Casual Sebum Content,” Archives of Dermatology, Vol. 127, No. 12, 1991, pp. 1806-1809.
M. Q. Man, S. J. Xin, S. P. Song, S. Y. Cho, X. J. Zhang, C. X. Tu, K. R. Feingold and P. M. Elias, “Variation of Skin Surface pH, Sebum Content and Stratum Corneum Hydration with Age and Gender in a Large Chinese Population,” Skin Pharmacology and Physiology, Vol. 22, No. 4, 2009, pp. 190-199. doi:10.1159/000231524
E. H. Choi, M. Q. Man, P. Xu, S. Xin, Z. Liu, D. A. Crumrine, Y. J. Jiang, J. W. Fluhr, K. R. Feingold, P. M. Elias and T. M. Mauro, “Stratum Corneum Acidification Is Impaired in Mod-erately Aged Human and Murine Skin,” Journal of Investigative Dermatology, Vol. 127, No. 12, 2007, pp. 2847-2856. doi:10.1038/sj.jid.5700913
J. W. Fluhr, J. Kao, M. Jain, S. K. Ahn, K. R. Feingold, and P. M. Elias, “Generation of Free Fatty Acids from Phospholipids Regulates Stratum Corneum Acidification and Integrity,” Journal of Investigative Dermatology, Vol. 117, No. 1, 2001, pp. 44-51. doi:10.1046/j.0022-202x.2001.01399.x
R. Ghadially, B. E. Brown, S. M. Sequeira-Martin, K. R. Fein-gold and P. M. Elias, “The Aged Epidermal Permeability Barrier. Structural, Functional, and lipid Biochemical Abnormalities in Humans and a Senescent Murine Model,” Journal of Clinical Investigation, Vol. 95, No. 5, 1995, pp. 2281-2290. doi:10.1172/JCI117919
J. Blaak, D. Lüttje, S. M. John and N. Y. Schürer, “Irritability of the Skin Barrier: A Comparison of Chronologically Aged and Photoaged Skin in Elderly and Young Adults,” European Geriatric Medicine, Vol. 2, No. 4, 2011, pp. 208-211. doi:10.1016/j.eurger.2011.05.011
R. Gunathilake, N. Y. Schurer, B. A. Shoo, A. Celli, J. P. Ha-chem, D. Crumrine, G. Sirimanna, K. R. Feingold, T. M. Mauro and P. M. Elias, “pH-Regulated Mechanisms Account for Pigment-Type Differences in Epidermal Barrier Function,” Journal of Investigative Dermatology, Vol. 129, No. 7, 2009, pp. 1719-1729. doi:10.1038/jid.2008.442
H. Dickel, T. M. Bruckner, S. M. Erdmann, J. W. Fluhr, P. J. Frosch, J. Grabbe, H. Loffler, H. F. Merk, C. Pirker, H. J. Schwanitz, E. Weisshaar and J. Brasch, “The ‘Strip’ Patch Test: Results of a Multicentre Study towards a Standardization,” Archives of Dermatological Research, Vol. 296, No. 5, 2004, pp. 212-219. doi:10.1007/s00403-004-0496-x
M. Kober, “Bestimmung des Hautoberfl?chen-pH bei Probanden: Methodik und Ergebnisse im Rahmen klinischer Studien,” In: O. Braun-Falco and H. C. Korting, Ed., Hautreinigung mit Syndets, Springer Verlag, Berlin, 1990, pp. 57-66.
R. Gfatter, P. Hackl and F. Braun, “Effects of Soap and Deter-gents on Skin Surface pH, Stratum Corneum Hydration and Fat Content in Infants,” Dermatology, Vol. 195, No. 3, 1997, pp. 258-262.
A. O. Barel, R. Lambrecht, P. Clarys, B. M. Morrison Jr. and M. Paye, “A Comparative Study of the Effects on the Skin of a Classical Bar Soap and a Syndet Cleansing Bar in Normal Use Conditions and in the Soap Chamber Test,” Skin Research and Technology, Vol. 7, No. 2, 2001, pp. 98-104. doi:10.1034/j.1600-0846.2001.70208.x
H. M. Gunathilake, G. M. Sirimanna, and N. Y. Schurer, “The pH of Commercially Available Rinse-off Products in Sri Lanka and Their Effect on Skin pH,” Ceylon Medical Journal, Vol. 52, No. 4, 2007, pp. 125-129.
H. C. Korting, K. Hubner, K. Greiner, G. Hamm and O. Braun-Falco, “Differences in the Skin Surface pH and Bacterial Microflora due to the Long-Term Application of Synthetic Detergent Preparations of pH 5.5 and pH 7.0. Results of a Crossover Trial in Healthy Volunteers,” Acta Derma-to-Venereologica, Vol. 70, No. 5, 1990, pp. 429-431.
E. Kim, S. Kim, G. W. Nam, H. Lee, S. Moon and I. Chang, “The Alkaline pH-Adapted Skin Barrier is Disrupted Severely by SLS-Induced Irritation,” International Journal of Cosmetic Science, Vol. 31, No. 4, 2009, pp. 263-269. doi:10.1111/j.1468-2494.2009.00491.x
S. Stenzaly-Achtert, A. Sch?lermann, J. Schreiber, K. H. Diec, R. Rippke and S. Bielefeldt, “Axillary pH and Influence of Deodorants,” Skin Research and Technology, Vol. 6, No. 2, 2000, pp. 87-91. doi:10.1034/j.1600-0846.2000.006002087.x
R. R. Wickett and C. M. Trobaugh, “Personal Care Products,” Cosmetics & Toiletries, Vol. 105, No. 7, 1990, pp. 41-46.
A. Post, M. Gloor and W. Gehring, “über den Einfluss der Hautwaschung auf den Haut-pH-Wert,” Dermatologische Monatsschrift, Vol. 178, No. 5, 1992, pp. 216-222.
J. W. Fluhr, M. Mao-Qiang, B. E. Brown, J. P. Hachem, D. G. Moskowitz, M. Demerijan, M. Haftek, G. Serre, D. Crumrine, T. M. Mauro, P. M. Elias and K. R. Feingold, “Functional Consequences of a Neutral pH in Neonatal Rat Stratum Cor-neum,” Journal of Investigative Dermatology, Vol. 123, No. 1, 2004, pp. 140-151. doi:10.1111/j.0022-202X.2004.22726.x
I. Buraczewska and M. Lodén, “Treatment of Surfac-tant-Damaged Skin in Humans with Creams of Different pH Values,” Pharmacology, Vol. 73, No. 1, 2005, pp. 1-7.
S. Beauregard and B. A. Gilchrest, “A Survey of Skin Problems and Skin Care Regimens in the Elderly,” Archives of Derma-tology, Vol. 123, No. 12, 1987, pp. 1638-1643. doi:10.1001/archderm.123.12.1638
S. Ward, “Eczema and Dry Skin in Older People: Identification and Management,” British Journal of Community Nursing, Vol. 10, No. 10, 2005, pp. 453-456.
K. Weismann, R. Krakauer and B. Wanscher, “Prevalence of Skin Diseases in Old Age,” Acta Dermato- Venereologica, Vol. 60, No. 4, 1980, pp. 352-353.
R. A. Norman, “Geriatric Dermatology,” Dermatologic Therapy, Vol. 16, No. 3, 2003, pp. 260-268. doi:10.1046/j.1529-8019.2003.01636.x
C. O. Barland, P. M. Elias and R. Ghadially, “The Aged Epi-dermal Permeability Barrier: Basis for Functional Abnormali-ties,” In: P. M. Elias and K. R. Feingold, Ed., Skin Barrier, Taylor & Francis, New York, 2005, pp. 535-552.
Treatment of Aged Skin with a pH 4 Skin Care Product Normalizes Increased Skin Surface pH and Improves Barrier Function: Results of a Pilot Study — Oak Academic Publishing