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Cited by 131Skin Protection and Agingmelanin and skin pigmentationNonmelanoma Skin Cancer Studies

Sunscreens used at the beach do not protect against erythema: A new definition of SPF is proposed

Wulf, H.‐C., Stender, I.‐M., Lock‐Andersen, J.·1997·Photodermatology, Photoimmunology & Photomedicine
DOI 10.1111/j.1600-0781.1997.tb00215.x
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Abstract

Since sunscreens are recommended by doctors and used all over the world to protect against sun induced erythema, it is important to evaluate if sunscreens are used as recommended and if the intended effect is achieved. We refer to the findings of several studies performed on people at risk of sun‐burning at beaches in the vicinity of Copenhagen, Denmark. On a sunny day at the beach 65% of the sunbathers used one or more sunscreens. Of these, 46% used the sunscreen all over the body and a median sun protection factor (SPF) of 5–6 was used. The sunbathers used 0.5 mg/cm 2 of sunscreen independent of skin type. Of the sunscreen users, 43%> applied the sunscreen after arriving at the beach and 43% reapplied the sunscreen after swimming. The sun exposure time and the sun exposure dose were almost identical among sunscreen users and non‐users. Self‐assessed redness of the skin demonstrated that more sunscreen users than non‐users reported to be red the day after sun exposure, 42 and 34%, respectively. Theoretical calculations support this finding and show a drastic reduction in the achieved photoprotection if a thinner layer than in the test situation is used. Sunscreens do not protect against erythema if not used as intended. Instead of changing people's habits, we suggest modifying the test method by adjusting the amount of sunscreen to that used in real life situations, 0.5 mg/cm 2.

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Crossref · 10.1111/j.1600-0781.1997.tb00215.x

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  • Sun protection factor is measured at 2 mg per cm2, yet in actual use, sunscreen application is only 0.4-0.5 mg per cm2.

    “Sun protection factor is measured at 2 mg per cm 2 , yet in actual use, sunscreen application is only 0.4-0.5 mg per cm 2 (Wulf et al, 1997;Autier et al, 2001).”

    From Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin (2005) · cites this paper as Wulf et al, 1997

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Authors
Wulf, H. ‐., Stender, I. ‐., & Lock‐Andersen, J.
Affiliations
University of Copenhagen (DK)
Corresponding author
Wulf, H.‐C.
ORCID
Wulf, H.‐C.
Venue
Photodermatology, Photoimmunology & Photomedicine
Publisher
Wiley
Published
1997-08
Volume
13
Issue
4
Pages
129-132
ISSN
  • 0905-4383 (ISSN-L)
  • 1600-0781
DOI
10.1111/j.1600-0781.1997.tb00215.x
OpenAlex
W2031073390
Cited by
131
References
0
Citations by year
2025: 2 · 2024: 1 · 2022: 1 · 2021: 2 · 2020: 2 · 2019: 7 · 2018: 3 · 2017: 6 · 2016: 3 · 2015: 1 · 2014: 1 · 2013: 1 · 2012: 6
FWCI
8.98
Type
journal article
Language
en
Open access
closed
Licence
onlinelibrary.wiley.com/termsAndConditions#vor (vor, 5149 d)
Locations
  • Photodermatology Photoimmunology & Photomedicine (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Dermatology › Skin Protection and Aging
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › melanin and skin pigmentation
  • Health Sciences › Medicine › Epidemiology › Nonmelanoma Skin Cancer Studies
Keywords
sunscreen use, sun protection factor, sunburn, erythema, photoprotection, skin redness
MeSH terms
Administration, Cutaneous, Body Surface Area, Denmark, Erythema, Female, Humans, Male, Radiation Dosage, Risk Factors, Self-Assessment, Self Care, Sunburn, Sunlight, Sunscreening Agents, Swimming, Time Factors, United States, United States Food and Drug Administration

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