Back to business protecting the consumer via daily photoprotection PJ Matts PhD and JF Nash PhD The Procter & Gamble Company London and Cincinnati
WHY USE A SUNSCREEN? 4 June 2013 Sun Protection for the 21st Century 2
Sunscreen Concerns Environmental Working Group 2013 Surprising facts about sunscreen!! (5 of the 9 listed) There s no proof that sunscreens prevent most skin cancer. Sunscreen does not protect skin from all types of sun damage. Some sunscreen ingredients disrupt hormones and cause skin allergies. Mineral sunscreens contain nanoparticles. If you avoid sun, check your vitamin D levels.
Sunscreen Concerns Other frequently-voiced concerns: SPF is misleading because users do not apply the dose, i.e., 2 mg/cm 2 used in clinical testing; Use of sunscreen encourages greater sun exposure (i.e., compensatory hypothesis); Sunscreen ingredients are photo-unstable; No or not enough UVA protection;
New Enquiry: Did sunscreens cause the 7-1 Brazilian defeat to Germany?? 4 June 2013 Sun Protection for the 21st Century 5
Do you know what s easier than putting on sunscreen? Not going outside Jim Gaffigan
WHY USE A SUNSCREEN?
... because The scientific evidence linking solar ultraviolet radiation (UVR) to acute, e.g., sunburn, and chronic, e.g., skin cancer and photoageing, skin damage is indisputable. AND Sunscreens decrease the rate / dose of solar UVR thereby reducing the risk of such damage.
Epidemiological Evidence: Methods Green et al. (1994) The Nambour skin cancer and actinic eye disease prevention trial: design and baseline characteristics of participants. Controlled Clinical Trials 15:512-522. Working hypothesis:... photodamage to skin is cumulative and progressive; that continuing exposure to UVR promotes skin cancer; and, thus, that primary prevention is possible in adults despite degenerative and premalignant changes that may have already arisen from past exposure 4 June 2013 Sun Protection for the 21st Century 9
Epidemiological Evidence: Methods
Epidemiological evidence: Methods 1621 randomly chosen residents of Nambour township between the ages of 20 69 yrs participated in this study. Design: 2 x 2 factorial; subjects assigned to 1 of 2 main treatment groups: daily use of SPF16 broad-spectrum sunscreen Cream: 8% 2-ethylhexyl-p-methoxycinnamate + 2% 4-tert-butyl-4 -methoxy-4- dibenzoylmethane, water resistant; apply layer to all exposed sites on the head, neck, arms, and hands every morning with reapplication after sweating, bathing or long sun exposure. comparison group continued sunscreen of any SPF as usual, including not at all. The authors state: Allocation of a placebo sunscreen to the control group was unethical, given the subtropical location. Those not in sunscreen group asked to continue application of sunscreen, any SPF, at their discretion, usually recreational.
Epidemiological evidence: Methods taken from: Green et al. 2011
Epidemiological evidence: Results (1) The results of the Nambour skin cancer and actinic eye disease prevention trial: Reduction in actinic / solar keratosis, the suspected precursor of squamous cell carcinoma Darlington et al. (2003) A randomized controlled trial to assess sunscreen application and beta carotene supplementation in the prevention of solar keratoses. Archives of Dermatology 139: 51-455. Reduction in squamous cell carcinoma (SCC) Green et al. (1999) Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial. The Lancet 354: 723-729 van der Pols et al. (2006) Prolonged prevention of squamous cell carcinoma of the skin by regular sunscreen use. Cancer Epidemiology Biomarkers and Prevention. 15: 2546-2548
Epidemiological evidence: Results (2) No statistically sig reduction in basal cell carcinoma (BCC) Green et al. (1999) Daily sunscreen application and beta-carotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial. The Lancet 354: 723-729 Time to subsequent BCC using multiple-failure event model analysis found a lower estimated hazard among reinforced sunscreen user group, although not statistically significant. Pandeya et al. (2005) Repeated occurrence of basal cell carcinoma of the skin and multifailure survival analysis: follow-up data from the Nambour Skin Cancer Prevention Trial. American Journal of Epidemiology 161: 748-754. 4 June 2013 Sun Protection for the 21st Century 14
Epidemiological evidence: Results (3) Long-term follow-up of this randomized trial showed that, among adults age 25-57 years, regular application of SPF 15+ sunscreen in a 5-year period appeared to reduce the incidence of new primary melanomas for up to 10 years after trial cessation. Green et al. (2011) Reduced melanoma after regular sunscreen use: randomized trial follow-up. Journal of Clinical Oncology 29: 257-263.
Epidemiological evidence: Results (5) Wearing a hat, long sleeves, sunglasses and use of sunscreen or umbrella were not associated with vitamin D status after adjustments, including after stratification by time outdoors. people who stayed in the shade had lower vit D then those who did not, which remained in those who spent less than 50% of their time outdoors. Jayaratne et al. (2012) Sun protection and vitamin D status in an Australian subtropical community. 4 June 2013 Sun Protection for the 21st Century 16
Epidemiological evidence: Results (6) Compliance Regular application of sunscreen to the face, head and neck can be maintained at a high frequency of use (3-4 times / week). Non-users were converted to regular application after 4.5 yr of daily use. van der Pols, et al. (2006) Long-term increase in sunscreen use in an Australian community after a skin cancer prevention trial. Preventive Medicine 42: 171-176
Epidemiological evidence: Results (7) Compliance: Daily application of a sunscreen reduced skin damage produced by solarsimulated UVR exposure compared to intermittent use of higher SPF products Phillips, TJ, Bhawan, J., Yaar, M., Bello, Y, LoPiccolo, D and Nash JF, (2000) Effect of daily versus intermittent sunscreen application on solar simulated UV radiation induced skin response in humans,, J Am Acad Dermatol., 43(4):610-8
Summary and Conclusions (1) Prospective (4.5 yr+), randomised population-based study in a genetically-sensitive population residing in subtropical region found daily use of SPF 16 broadspectrum sunscreen significantly reduced the incidence and number of SCC and melanoma after 20 years compared to intermittent sunscreen users. Trend toward reducing the appearance of BCC. Use of sunscreen can be learned. Sun protection behavior can be maintained without affecting vitamin D. 4 June 2013 Sun Protection for the 21st Century 19
Summary and Conclusions (2) Using principles of evidence-based medicine and the strength of the Nambour study, the daily application of an SPF16 broad spectrum sunscreen to the face, neck, forearms and hands will reduce the risk of non-melanoma and melanoma skin cancers.
SO If sunscreen use reduces solar UVR and the risk of skin cancer, why do so few people use sunscreens? AND What can be done to get more people to use sun protection strategies including sunscreens earlier and more frequently?
Green s Nambour studies represent a 14 year experiment But what about the 1,000,000 year experiment called Evolution...?
The photoprotective effect of hair Solar Zenith Angle From: Parisi et al., 2009
Wrinkle Area Fraction (image analysis) Facial Wrinkling by Race and Age Group (Los Angeles) 0.10 0.08 Caucasian (n=439) Hispanic (n=435) African American (n=310) 0.06 0.04 0.02 0.00 Teens 20s 30s 40s 50s 60s Age Group Data courtesy of GG Hillebrand
Wrinkle Area Fraction Facial wrinkling vs age by skin lightness 0.10 0.08 0.06 0.04 L* range n 61-70 305 52-61 602 43-52 254 34-43 240 25-34 34 0.02 0.00 0 10 20 30 40 50 60 70 80 Age
Wrinkle area fraction The relationship between age and the detection of wrinkles in dorsal hand and facial images by algorithm (Caucasian skin) 0.4 0.35 Hand Wrinkle Area Frac. Face Wrinkle Area Frac. 0.3 0.25 0.2 0.15 0.1 0.05 0 10 20 30 40 50 60 70 Age (years) Data P Matts on file
The Contact SIAscope ( SIA = Spectrophotometric Intracutaneous Analysis) Developed by Cambridge (UK)-based medical imaging company, Astron Clinica Contact scanner, placed on the skin surface Rapid (<5sec), non-invasive and highly portable Maps concentration and spatial distribution of melanin, haemoglobin and collagen Utilises 4 discreet wavebands (3 in the visible, 1 in near-ir) IP lies in unique, patented optical de-convolution algorithms 12mm acquisition area
Visible white light images Young Aged Note: images selected randomly from 400 base; imaged area approx 12mm diameter
Melanin maps (same images) Young Aged Note: darker gray scale = more melanin
Haemoglobin maps (same images) Young Aged Note: darker gray scale = more haemoglobin
Close-up of melanin map from young subject
Close-up of melanin map from aged subject
Close-up of haemoglobin map from young subject
Close-up of haemoglobin map from aged subject
Total melanin (arbitrary units) Total melanin concentration by age Means and standard errors 146 136 126 116 106 96 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups n=400, data collected in Reading, UK
Melanin SD (internal image) Melanin heterogeneity by age Means and standard errors 16.7 14.7 12.7 10.7 8.7 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups n=400, data collected in Reading, UK
Melanin spot total area (pixels x10 3 ) Melanin total spot area by age Means and standard errors 42 37 32 27 22 17 12 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups n=400, data collected in Reading, UK
Melanin spot number (per image) Melanin spot number by age 13 12 11 10 9 8 7 Means and standard errors 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups n=400, data collected in Reading, UK
Total haemoglobin (arbitrary units) Total haemoglobin concentration by age 34 Means and standard errors 31 28 25 22 19 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups n=400, data collected in Reading, UK
Haemoglobin SD (internal image) Haemoglobin heterogeneity by age 7.2 6.7 6.2 5.7 5.2 4.7 4.2 Means and standard errors 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups n=400, data collected in Reading, UK
Pareidolia
The beauty obsession Evolution has shaped our minds to help us survive Our ancestors have adapted to environmental conditions and social situations and have developed mental capacity to deal with complex interactions Mate selection, i.e. finding a perfect partner, is probably the most important social task that humans have to master in life wrong decisions are very costly...!
Mate selection relies upon rapid (<0.5sec) assessments of age and health because, ultimately, these are linked intrinsically to fertility and reproductive potential......and facial skin is a pivotal component of this process
Visible Skin Colour Distribution Plays a Major Role in the Perception of Age, Attractiveness and Health in Female Faces, Fink, B., Grammer, K. and Matts, P.J., Evolution and Human Behaviour, 27(6), 433-442, 2006 Colour homogeneity and visual perception of age, health and attractiveness of female facial skin, Matts, P.J, Fink, B., Grammer, K. and Burquest, M., J. Am. Acad. Dermatol., 57(6), 977-984, 2007 The effects of skin colour distribution and topography cues on the perception of female facial age and health, Fink, B. and Matts, P.J., Euro. J. Dermatol. Venereol., 493-498, 2008 Visual Attention to Variation in Female Facial Skin Colour Distribution, Fink, B., Matts, P.J., Klingenberg, H., Kuntze1, S., Weege, B. and Grammer, K., J. Cosmet. Derm., 7(2), 155-161, 2008 Visible skin condition and perception of human facial appearance, Samson, N., Fink, B. Matts, P.J., Int J Cosmet Sci., 32(3):167-84, 2010 Chronic sun damage and perception of age, health and attractiveness, Matts, P.J. Fink, B., Photochem. Photobiol. Sci., 9(4):421-31, 2010 Visible changes of female facial skin surface topography in relation to age and attractiveness perception, Samson, N., Fink, B., Matts, P.J., Dawes, N.C. and Weitz, S.M., J. Cosmet. Dermatol., 9, 79 88, 2010 Differences in visual perception of age and attractiveness of female facial and body skin, Fink, B., Röder, S., Burquest, M., Johnson, R., and Matts, P.J., Int. J. Cosmet. Sci, 33(2):126-31, 2011 Interaction of skin colour distribution and skin surface topography cues in the perception of female facial age and health, Samson, N., Fink, B. and Matts, P.J., J. Cosmet. Dermatol., 10(1):78-84, 2011 Does a woman s skin colour indicate her fertility level? Preliminary findings, Samson, N., Fink, B. and Matts, P.J., Swiss Journal of Psychology, 70 (4), 2011 Visible skin colouration predicts perception of male facial age, health and attractiveness, Fink, B., Bunse, L., Matts, P.J. and D Emiliano, D., Int. J. Cosmet. Sci., 34(4):307-10, 2012 Colour homogeneity and visual perception of age, health and attractiveness of male facial skin, Fink, B., Matts, P.J., D Emiliano, D., Bunse, L., Weege, B. and Röder, S., Euro. J. Dermatol. Venereol., 26(12):1486-92, 2013 Visual attention to and perception of undamaged and damaged versions of natural and coloured female hair, Fink, B., Neuser, F., Deloux, G., Röder, S. and Matts, P.J., J. Cosmet. Derm., 12(1):78-84, 2013
The role of skin chromophores in perception of age, health and attractiveness 170 rendered stimuli using original colour distribution from subjects aged 10-70 years 430 members of the public (198 males and 232 females) aged 13 76 judged the stimuli for perceived age, health and attractiveness
Perceived Age Chronological vs Perceived Age 30 28 26 24 22 20 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50 50-55 55-60 60-65 65-70 Chronological Age (5 year groups) rho = 0.72, p<0.0001, perceived age range: 17 37 years
The effects of skin colour distribution and topography cues on the perception of female facial age and health, Fink, B. and Matts, P.J., Euro. J. Dermatol. Venereol., 22(4), 493-498, 2008 Visual Attention to Variation in Female Facial Skin Colour Distribution, Fink, B., Matts, P.J., Klingenberg, H., Kuntze, S., Weege, B. and Grammer, K., J. Cosmet. Derm. 7(2), 155-161, 2008 We pay greater visual attention to faces with more even colouration and less to those with uneven colouration There is a relative weighting of perception of wrinkles and uneven colouration where: wrinkling codes more for perception of age, whereas colour evenness codes more for perception of health
Cropped cheek image from older subject Cropped cheek image from younger subject Original
200 people judged 170 cropped cheek images We do not need facial context to make profound judgements of age, health and attractiveness from skin Matts, P.J. et al., JAAD, 2007
Colour Homogeneity Chronological age vs colour evenness (mathematical measurement of original image) 930 890 850 810 770 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50 50-55 55-60 60-65 65-70 Age Group Matts, P.J. et al., JAAD, 2007
Colour Homogeneity Colour homogeneity (original image) vs self-assessed lifetime sun exposure 900 880 860 840 820 800 Low Medium High Self-assessed lifetime sun exposure
Melanin SD (internal image) Pregnancy rate (%)* Melanin heterogeneity and fertility by age 16.7 100 90 14.7 12.7 80 70 60 50 10.7 8.7 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-55 56-59 60-64 65-70 Age Groups 40 30 20 10 * Data from Carcio, 1998
Daily cutaneous photodamage by sub-erythemal doses of UVR matters...
...we make profound judgements of age and health and, therefore, of attractiveness based on resulting skin quality...
Because of daily exposure to solar UVR: <0.2% of the UK population develop a skin cancer annually 100% of the UK population is judged older, less healthy and less attractive in daily life
Original Eumelanin Oxyhaemoglobin
Summary Compelling evidence that long-term daily use of sunscreens reduces the risk of skin cancer and photoageing Compelling evidence that chronic photodamage effects profound judgement of age, health and attractiveness, that can be moderated by daily photoprotection Protection can be moderate, aesthetics can drive compliance Despite this evidence, the majority still do not take advantage of these benefits First principles of Evolutionary Psychology may prove useful in influencing behaviour change through positive messages promoting youth, health and attractiveness