Original article
High-SPF sunscreens (SPF ≥ 70) may provide ultraviolet protection above minimal recommended levels by adequately compensating for lower sunscreen user application amounts

Previously presented as a poster at the 69th American Academy of Dermatology Annual Meeting, New Orleans, Feb. 4-8, 2011.
https://doi.org/10.1016/j.jaad.2012.02.029Get rights and content

Background

The manner in which consumers apply sunscreens is often inadequate for ultraviolet protection according to the labeled sun protection factor (SPF). Although sunscreen SPFs are labeled by testing at an application density of 2 mg/cm2, the actual protection received is often substantially less because of consumer application densities ranging from 0.5 to 1 mg/cm2. High-SPF sunscreens may provide more adequate protection even when applied by consumers at inadequate amounts.

Objective

We sought to measure the actual SPF values of various sunscreens (labeled SPF 30-100) applied in amounts typical of those used by consumers.

Methods

Actual SPF values were measured on human volunteers for 6 sunscreen products with labeled SPF values ranging from 30 to 100, applied at 0.5, 1.0, 1.5, and 2.0 mg/cm2.

Results

There was a linear relationship between application density and the actual SPF; sunscreens with labeled SPF values of 70 and above provided significant protection, even at the low application densities typically applied by consumers. Sunscreens labeled SPF 70 and 100 applied at 0.5 mg/cm2 provided an actual SPF value of, respectively, 19 and 27.

Limitations

The study was conducted in a laboratory setting under standardized conditions and results are extrapolated to actual in-use situations.

Conclusion

Sunscreens with SPF 70 and above add additional clinical benefits when applied by consumers at typically used amounts, by delivering an actual SPF that meets the minimum SPF levels recommended for skin cancer and photodamage prevention. In contrast, sunscreens with SPF 30 or 50 may not produce sufficient protection at actual consumer usage levels.

Section snippets

Methods

This study evaluated the effects of various application densities on the actual SPF values of 6 sunscreen products, with labeled SPFs ranging from 30 to 100. The investigation was designed with a 2-step approach. An initial study (study A) was conducted on 251 volunteers to determine the SPF value of 6 sunscreens (labeled SPF from 30-100) at 4 different application densities (0.5, 1.0, 1.5, and 2.0 mg/cm2). The second study (study B), conducted on 76 volunteers after the results of study A were

Study A

A total of 237 subjects completed the study and 233 were included in SPF calculations. Data for 4 subjects were excluded because of protocol violations.

Mean SPF values and statistical information for each test product and application density are presented in Table II. For all 6 test sunscreens, the mean SPF value was progressively lower with lower application densities. However, reduced application densities yielded proportionately higher mean SPF values for products with higher labeled SPFs.

Discussion

In recent years, advancements in sunscreen formulations and access to photostabilized UV filter technology have allowed companies to manufacture products with SPF value up to 100. The marketing of very high–SPF products (SPF >50) has spurred an ongoing debate questioning their added clinical benefits. Indeed, comparative investigations on very high–SPF sunscreens are scant. Russak et al25 conducted a split-face, double-blind, randomized study comparing an SPF 50 with an SPF 85 product. A total

References (31)

  • D.R. English et al.

    Case-control study of sun exposure and squamous cell carcinoma of the skin

    Int J Cancer

    (1998)
  • R.M. van Dam et al.

    Risk factors for basal cell carcinoma of the skin in men: results from the health professionals follow-up study

    Am J Epidemiol

    (1999)
  • J.P. Ortonne

    Photobiology and genetics of malignant melanoma

    Br J Dermatol

    (2002)
  • American Academy of Dermatology. Melanoma. Available from:...
  • L.K. Roberts et al.

    Sunscreen lotions prevent ultraviolet radiation-induced suppression of antitumor immune responses

    Int J Cancer

    (1997)
  • Cited by (0)

    Funded in full by Neutrogena Corp; the preparation of this manuscript was sponsored in full by Johnson and Johnson Consumer Companies.

    Disclosure: Drs Ou-Yang and Appa are employees of Neutrogena Corp, the manufacturer of two of the sunscreens tested. Dr Cole is an employee of Johnson and Johnson Consumer Companies, a sister company of Neutrogena Corp. Mr Stanfield is an employee of Suncare Research Laboratories, the independent testing laboratory that received compensation for conducting this study, and he is currently a consultant to Galderma Laboratories LP. Dr Rigel is a consultant for Neutrogena Corp, Johnson and Johnson Consumer Companies, Beiersdorf, and P&G.

    View full text