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INTERVIEW
Meeting the leading scientists
in the field of dermatology, skin cancer prevention,
sun protection and sunscreen formulation
According to leading dermatologists and skin cancer experts, sunscreens are the best protection against skin cancer
after sun avoidance and adequate protective clothing. To obtain a full prevention, however, sunscreens must be used
according to certain criteria: the highest possible sun protection factor (SPF) should be used and they must be
employed correctly by applying them at least 30 minutes prior to exposure, in generous amounts and by frequently
re-applying them.
According to literature, skin cancer is the most common cancer form in the USA. In Europe other cancer forms are
more prevalent, but also here skin cancer has been clearly identified as one form of cancer that will become more
important in public health terms in the coming decades.
H&PC Today decided to have a word with the leading specialists in this field in order to get an overview of a state of
the art in sun protection and prevention of skin cancer in the population also form the sociological and common sun
exposure habits point of view.
Florian Weighardt, H&PC Today, TKS Publisher
Uli Osterwalder
BASF, Marketing Manager and Scientific Adviser for Sun Care on sun protection and sunscreens
Uli Osterwalder, Marketing Manager and Scientific Adviser for Sun Care at BASF, studied Chemical Engineering at ETH
Zurich in Switzerland and at the University of Houston in Texas, USA. He started his career at Basel-based Ciba-Geigy
in 1979, where he first developed a phosgene generator in central process development. He went on to build on his
leadership skills in project management and process analytics. Later, at Ciba Specialty Chemicals, Osterwalder helped
establish new business development in Fabric Care and Personal Care. In his current position at BASF, he is Marketing
Manager and Scientific Adviser for Sun Care. He also participates in an ISO working group focusing on developing UV
protection assessment methods, and has authored and co-authored a number of articles for scientific journals as well
as book chapters on sun protection.
In Europe, skin cancer is expected to become increasingly
prevalent over the coming decades, while in the US, it
is already one of the most common types of cancers.
Exposure to ultraviolet (UV) radiation, which can also cause
premature ageing of the skin, has been identified as the most
preventable risk factor. How important is the use of sunscreen
in this context?
In recent years, studies have demonstrated that broadspectrum sunscreens, when applied correctly and used along
with other protective measures, are effective in preventing
the harmful effects of UV radiation on the skin – including skin
cancer and ageing.
This is important because it’s true that skin cancer is the
most common cancer. It is already one in every three
cancers diagnosed, and its global incidence continues to
rise. According to the World Health Organization (WHO),
between two and three million cases of non-melanoma skin
cancers (BCC and SCC) and 132,000 cases of melanoma
occur globally each year. Although malignant melanoma is
by far the rarest of the three types of skin cancer, it accounts
for 75% of skin cancer deaths. WHO is also estimating that a
further 10% decrease in ozone levels will lead to an additional
300,000 cases of non-melanoma and 4,500 cases of
melanoma skin cancer each year. In the US, one in every five
Americans will develop skin cancer in their lifetime according
to statistics from the Skin Care Foundation.
Broad-spectrum sunscreen protects the skin against both UVB
and UVA rays. Although UVA is less likely than UVB to cause
sunburn, it penetrates the skin more deeply and is considered
to be the chief culprit behind wrinkling and leathering of the
skin, as well as other aspects of premature ageing. This is why
an increasing number of daily skincare products already
contains the same UV filters as used in sunscreens.
Monographic special issue: Sun care - H&PC Today - Household and Personal Care Today - vol. 10(4) - July/August 2015
25
What are the benefits of sunscreen, and does it have any
limitations?
Sunscreens contain organic or inorganic UV filters that absorb
the radiation on the surface of the skin. The sun protection
factor (SPF) indicates the protection against erythema –
reddening of the skin –compared to the self-protection by the
natural skin pigmentation. For example, if it takes the skin 20
minutes to start reddening without sun protection, using an
SPF 15 sunscreen should protect the skin from reddening for
15 times longer – so for about five hours. Sunscreen has long
been effective at filtering UVB, but until recently it provided
little UVA protection. New ingredients have improved
sunscreen’s defenses, but there are still many sunscreens and
especially day creams with insufficient UVA protection.
When it comes to product performance and claims, there is
a definite need for global standards and tough regulations
so that consumers can trust the efficacy of sunscreen. There
has been a lot of debate about how effective sunscreen
really is and, in some regions, lower standards and the wide
range of sun care products available on the market result in
differences in quality and performance.
The most critical factor in sun protection is ensuring consumers
apply sunscreen correctly and frequently – yet this remains a
major challenge. Educated consumers are more likely to be
aware of their skin type and to choose the right sunscreen
for them. However, lots of people are still using products that
don’t offer them adequate protection. This, in turn, leads to a
false sense of security and puts them at even greater risk.
Both government and industry have made a concerted effort
to educate the public and encourage people to adopt
behaviors that protect them from the sun: These include using
sunscreen, seeking shade, wearing appropriate clothing, or
even avoiding going out in the sun altogether.
Is there such a thing as “safe” tanning?
Above all, safe tanning involves limiting the amount of time
spent in the sun, especially between the hours of 10 a.m.
and 2 p.m., when the sun’s rays are strongest. Sunbathers
are also advised to apply a broad-spectrum sunscreen of at
least SPF 15.
This should be applied evenly, in recommended amounts, 30
minutes before going out in the sun – as full sun protection
requires some time to develop. After that, the sunscreen
should be reapplied every two hours, or after swimming,
playing, exercising or working outdoors.
A tan indicates that the skin is either redistributing the
pigment already available in the skin, or that it’s producing
more melanin granules and spreading them out. But as
dermatologists continue to emphasize, tanning is actually a
sign of skin damage and should not be encouraged.
What are the most important requirements for a sunscreen?
The four basic requirements from the manufacturer point
of view are efficacy, safety, registration, and patent
freedom. For a sun care product to succeed on the
market, it needs to meet strict performance requirements,
including high SPF value and UVA protection. Standards
have become more stringent over the years and there
are now special criteria that have to be fulfilled, including
26
the European Union recommendation that the UVA
protection factor must be at least one-third of the sun
protection factor’s value (UVA-PF ≥ 1/3 SPF). So, from a
market perspective, providing the right combination of
filters, photo-stability, water resistance and certain sensory
properties is the most crucial thing.
Furthermore, the product must satisfy consumers. It has to
be gentle on the skin, have a light texture, absorb quickly,
and possess an attractive sensory profile. The current trend
is for lighter formulation textures – products that feel nice
on the skin during and after application, and that are
visually appealing and smell good. There’s also increasing
demand for quick and easy-to-use solutions, which is a
clear reflection of the “convenience” megatrend. And
we’re increasingly seeing daily-use skincare products that
incorporate UV protection.
Ideally, how should sunscreen be formulated to ensure that it’s
a really reliable tool for sun protection?
When formulating the ideal sunscreen, two things should be
considered:
•
First, it should offer uniform protection across the entire
UVB/UVA range (290–400 nm) – which is similar to the
protection provided when avoiding the sun completely
or covering up. Experiments have demonstrated how well
this can be achieved by combining UVB, UVA and
broad-spectrum filters. With the help of particulate UV
filters, sunscreens can protect to the limit of UVA-I and up
to short visible light wavelengths of less than 400 nm.
•
Secondly, as compliant application remains a problem,
the ideal sunscreen should be as attractive as possible to
consumers. Creating pleasing formulations that offer
popular sensory and tactile profiles should be considered
just as important as achieving a specific protection profile
or fulfilling a certain SPF or UVA category.
How is the efficacy of sun protection formulations currently
assessed?
Methods for testing the efficacy of a sunscreen, or its UVA
protection, have been adopted by regulatory bodies in
Japan, the European Union, Australia and the United States –
but they vary from country to country.
We believe that the assessment of UVA protection should
be linked with the SPF value, as recommended by the
European Commission, which states that UVA-PF/SPF ≥ 1/3.
Other UVA standards, such as the Boots star rating system
used in the UK and Ireland – which adopts a UVA/UVB ratio >
0.9 – go beyond EU recommendations and are more similar
to uniform UVB/UVA protection, which could be regarded as
ideal sunscreen performance.
Along with the development of testing and labelling
guidelines, assessment methods for measuring sun protection
efficacy have also been further improved. In-silico models
to calculate SPF and UVA protection metrics cannot
replace in-vivo testing of the final product – but they do
help formulators to evaluate combinations of different UV
filters. For instance, the BASF Sunscreen Simulator can help
manufacturers plan the composition of active ingredients in
a sunscreen formulation.
Monographic special issue: Sun care - H&PC Today - Household and Personal Care Today - vol. 10(4) - July/August 2015
What about assessing the performance of sunscreen products
in real-life conditions?
There are ways to assess performance of sunscreen under
real-life conditions. Besides measuring the SPF and UVA-PF
under laboratory conditions the spreading of the product
on the skin can be taken into account. Products that
spread easily and form a more or less uniform film on the
skin will rather provide the nominal SPF than products that
are difficult to distribute on the skin. The SPF achieved
is referred to as SPF in vivo veritas after a publication of
Pissavini and Diffey.
When it comes to sunscreen safety and regulatory
compliance, what’s the current status? How can nano
ingredients help?
UV filters are the best investigated ingredients in personal
care. They go through the scrutiny of a pre-marketing
assessment by the scientific committee for consumer safety
(SCCS) and approval by the EU commission (positive list in
Annex VI of the Cosmetics regulation). The safety of each
ingredient has to be assessed separately. There is no general
rule about whole classes of cosmetic ingredients.
Microfine particles that normally include some particles in
the nano range, i.e < 100nm) contribute to both efficacy
and safety of sunscreens as follows. With the help of
particulate UV filters, sunscreens can protect to the limit of
UVA-I and up to short visible light wavelengths of less than 400
nm, because particles provide a broader absorption spectrum
than soluble UV filters. Furthermore there is some scattering that
helps protecting. Regarding safety any nano particle is of a
much larger size than any soluble UV filter molecule; they thus
can practically not penetrate the skin. We can conclude for
sunscreens; if we see the nano declaration on the Ingredient
list, this means big, i.e. particles that do not penetrate the skin.
What are the latest trends in sunscreen formulation and to what
extent do these trends vary worldwide?
Looking at recent product launches, we can see a number
of different but also some similar trends across various regions.
When it comes to the types of products available, lotions,
creams and gels remain the most popular: Regardless of
region, they represent around 60% of the products recently
introduced to the market.
In North America, where almost 25% of new products
are launched, sprays – including emulsion sprays and,
increasingly, lipo-alcoholic clear continuous sprays – have
a significant market share. In Europe, emulsion sprays in
particular remain very popular. “Shake well before use”
products are popular in the Asia Pacific region, accounting
for 22% of products launched there compared with only 2% in
other major regions.
But looking beyond sunscreens alone, we are seeing the
introduction of more and more skincare products that offer
UV protection. Face care and foundation products, especially
blemish balm creams, made up around 20% of new sun
protection products launched last year in North America and
Europe, and about 10% in Latin America and Asia Pacific.
Unfortunately the consumer is not guaranteed that these
products provide sufficient UVA protection for lack of UVA
standards in these categories.
Anthony J. Alberg
Medical University of South Carolina, Charleston, SC on skin cancer prevention and sun protection
Anthony J. Alberg, Ph.D., M.P.H. is a cancer epidemiologist who is currently the Interim Director of the Hollings Cancer
Center of the Medical University of South Carolina (MUSC) in Charleston, South Carolina. He is a Professor in the Department
of Public Health Sciences and holds the Blatt Ness Endowed Chair in Oncology. He matriculated to MUSC from the Johns
Hopkins University Bloomberg School of Public Health. A central research focus for Dr. Alberg is on the epidemiology and
prevention of skin cancer. He and his colleagues have helped to characterize non-melanoma skin cancer as a marker
of increased risk of subsequent non-cutaneous malignancies and have been investigating potential mechanisms for this
association. Dr. Alberg has authored or co-authored more than 130 peer-reviewed publications related to these and other
topics in cancer epidemiology and cancer prevention.
What are the major forms of skin cancer?
The term “skin cancer” is commonly used to refer to all types
of cutaneous malignancies, but it is important to make some
key distinctions among the different types of skin cancer. The
broadest grouping is to distinguish malignant melanoma, or
cancer of the melanocyte, and keratinocyte carcinoma, or
cancer of keratinocytes, which is commonly referred to as
non-melanoma skin cancer. Another important distinction
is that keratinocyte carcinoma is comprised of two primary
histologic types, basal cell carcinoma (BCC) and squamous
cell carcinoma (SCC), with BCC more common than SCC by
a ratio of about 2:1.
Keratinocyte carcinoma is rarely fatal. Malignant
melanoma, on the other hand, is a much less common
form of skin cancer but accounts for the vast majority of
deaths from skin cancer. Each of these three types of skin
cancer-melanoma, BCC, and SCC--have unique features
to their distribution in populations, etiology, and clinical
characteristics.
In Europe, skin cancer has been identified as one form of
cancer that will become more important in public health
terms in the coming decades and in the USA it represents one
of the most frequent forms of cancer.
First and foremost, it is important to emphasize that
keratinocyte carcinoma is the type of cancer that is by far
the most common malignancy in the world, period. No other
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27
type of cancer comes close. To give an idea of how common
keratinocyte carcinoma is, in the US the number of patients
diagnosed with keratinocyte carcinoma in an average year
is 33% greater than all other cancers combined! We are
talking about a public health and medical care problem of
enormous proportions.
In terms of trends, the incidence and prevalence of both
melanoma and keratinocyte carcinoma are increasing in the
United States and globally.
What are the main causes of skin cancer? How important is
exposure to ultraviolet radiation in causing skin cancer?
The major environmental cause of skin cancer is exposure
to ultraviolet radiation. This is mostly from solar ultraviolet
radiation (sunlight). However, because of increasing trends
in the prevalence of usage, tanning bed use is of growing
concern as a source of exposure to ultraviolet radiation.
There is such a strong link between sunlight exposure and
skin cancer that this correlation can even be seen at
the population level, providing strong evidence that the
increasing trends in the occurrence of skin cancer are
primarily due to increased sun exposure.
It is important to note the strong dose-dependent relationship
between sun exposure and keratinocyte carcinoma.
As cumulative exposure to sunlight increases, there is
a commensurate increase in the risk for keratinocyte
carcinoma. Thus, even skin cancer diagnosed in elderly
persons is the end result of sun exposure that began during
childhood and adolescence.
Sun exposure has its pros and cons. Recent
epidemiological data suggest that in temperate latitudes
sunlight dose-dependently increases lifespan both due to
the induction of vitamin D synthesis and the UV induced
mobilisation of nitric oxide from skin stores which may be
responsible for the observed cardiovascular benefits of
sunshine. What do you think? Are we in front of a question
of balance?
The public health dilemma is that sun avoidance
to prevent skin cancer may compromise vitamin D
sufficiency, leading some to speculate that the benefits of
unprotected exposure to sunlight to increase cutaneous
vitamin D synthesis may outweigh the risks of skin cancer.
This is clearly a controversial stance. Also, rest assured
there is an industry with a vested interest in this topic: the
tanning bed industry. Further complicating matters, the
public is aware of the potential health benefits of vitamin
D as reports touting the health benefits of the “sunshine
vitamin” have received extensive media coverage.
Developing a policy based on advocating for
unprotected sun exposure is further complicated by the
fact that the level of sun exposure required to achieve
optimal concentrations of vitamin D is uncertain. The
relationship between sun exposure and vitamin D
synthesis in the skin is complex, as individuals produce
different amounts of vitamin D for a given dose of
sunlight, and the dose of sunlight depends on factors such
as the season of year, time of day, and latitude.
The heightened awareness of vitamin D in the general
population accentuates the public health importance of
28
resolving this controversy. The public needs clear guidance
on how best to navigate the challenging terrain between
the mixed medical and media messages that range from
sun avoidance for skin cancer prevention to the sunseeking, pro-vitamin D message.
A prudent public health strategy is to use vitamin D
supplements to maintain optimal vitamin D levels. This is a
“win-win” strategy by avoiding advocating for exposure to
the predominant cause of skin cancer while still enabling
the health-enhancing levels of vitamin D supplementation
to be achieved. This is also an increasingly viable
strategy, as more is learned about the high supplemental
vitamin D doses that humans can tolerate. Vitamin D
supplementation represents a path forward that allows
patients and the public to benefit from vitamin D’s health
enhancing effects—both known and yet to be proven-while remaining vigilant in preventing skin cancer.
Are there population subgroups who are more susceptible to
skin cancer than the general population?
Yes, clearly those most prone to developing skin cancer
have what is referred to as a “sun-sensitive phenotype”
that is comprised of a propensity to experience sunburn
upon exposure to sunlight. There is a spectrum of skin
types and the occurrence of skin cancer tends to be
concentrated among those whose skin is most sensitive
to the sun. The most sun-sensitive skin types tend to be
correlated with fair complexion, freckling, red hair, and
blue eye color.
Conversely, the populations with the lowest risk of skin
cancer tend to be those with darker skin pigmentation.
Even though people of color have lower risk of skin cancer
than fair-skinned Caucasians, it is important to note that
the risk is not zero.
What are the best preventive strategies one can adopt to
reduce skin cancer incidence?
Skin cancer prevention strategies focus on ways to
minimize unprotected sun exposure, particularly among
the high-risk groups of the population, namely those
with sun-sensitive phenotypes. Minimizing unprotected
sun exposure entails either sun avoidance strategies or
engaging in sun protective behaviors, such as use of
sunscreens on sun-exposed skin and use of sun-protective
clothing, hats, and sunglasses. Further, prevention
strategies need to minimize exposure to ultraviolet
radiation via tanning beds.
Policy-level preventive strategies at the population
level include the regulation of tanning beds and media
campaigns. The built environment is important, such as
ensuring that playgrounds and school yards have shaded
areas where children can be out of the sun. Further,
educational interventions are needed at the individual
level. For all ages, the physician-patient interaction
represents an important opportunity to address skin
cancer prevention behaviors. Because of the dosedependent relationship between sun exposure and skin
cancer risk, skin cancer prevention behaviors are relevant
to all age groups, but most important for children and
adolescents. This amplifies the importance of pediatric
Monographic special issue: Sun care - H&PC Today - Household and Personal Care Today - vol. 10(4) - July/August 2015
visits as an opportunity to educate new parents about
sun-protection behaviors for their children. Further, schoolbased interventions offer an important opportunity to
educate young people about the causes of skin cancer
and immediate steps they can take to prevent it.
In Australia and in other southern hemisphere countries
education-campaigns at school represent an important tool
in raising the conscience of the risks of sun exposure. Is this a
model which should be adopted elsewhere?
The combination of being situated at latitudes with high
intensity solar ultraviolet radiation and with a high proportion
of the population whose ancestry traces back to the United
Kingdom and hence with sun-sensitive phenotypes has led to
Australia having the highest skin cancer rates in the world and
tremendous challenges for skin cancer control efforts. Within
this challenging milieu, Australia has been a model for how
to respond to a striking epidemic of skin cancer. As a society,
they have addressed this problem with innovative intervention
approaches at the levels of policy, population, and individual,
and as a society they are reaping the benefits of this
investment. Thus, this is a model for other nations to follow.
To what extent can sunscreens be considered as efficient
preventive tools against skin cancer? How important is the
correct use of sunscreens?
Sunscreens are an important element of strategies for skin
cancer prevention. However, to realize the full prevention
potential of sunscreens, certain criteria need to be met. First, it
is important to use the highest possible accurately measured
sun protection factor (SPF), and second, it is critical to correctly
use the sunscreen by applying it in generous quantities on all
sun-exposed skin and then frequently re-applying sunscreen.
Far too often these criteria are not met, leading people into a
false sense of assurance and overexposure to sunlight.
Exposure to ultraviolet (UV) radiation is the most preventable
risk factor for skin cancer. Does a “safe” skin-tanning
behaviour exist?
I would be hesitant to say that there is a safe “skin-tanning”
behavior that exists, because for certain subgroups of the
population, there is clearly no safe level. This is particularly
true for fair-skinned individuals with skin that is most sensitive
to sunburn upon exposure to ultraviolet radiation.
Indoor skin tanning by means of UV-emitting devices
represents an important risk factor in the development of
skin cancer. Brazil fully banned the use of these devices for
cosmetic purposes followed by several Australian territories.
In Europe an increasing number of countries, starting from
France, have banned indoor tanning among minors. What do
you think about these measures?
Intentional exposure to indoor skin tanning from UVemitting devices causes skin cancer. From the public
health perspective, when the cause of a disease has
been identified in this way, any policy intervention that
either eliminates or reduces exposure is a step in a positive
direction toward reducing the population burden of skin
cancer. Greater reductions in the exposure to ultraviolet
radiation will have a greater impact on lowering skin
cancer rates.
Borrowing from tobacco control, which also has an industry
that manufactures and promotes a harmful product, this
problem can be addressed with a vast array of policy
levers. The spectrum of policy options includes prohibition,
restricting the minimum age of legal use, taxation,
consumer warnings and beyond. Clearly, the most extreme
policies will yield the greatest public health benefit, but any
steps toward minimizing use will reduce the occurrence
of skin cancer. The goal should thus be to maximize the
regulation of this industry based on what is feasible in a
given political situation.
Carolyn J. Heckman
Fox Chase Cancer Center, Philadelphia, PA on skin cancer prevention and sun protection
Carolyn Heckman, Ph.D.,is an Associate
Professor in the Cancer Prevention and
Control Program at Fox Chase Cancer
Center in Philadelphia, PA. She conducts
research full-time and is a licensed clinical
psychologist.
Q.Skin cancer is the most common cancer form in the USA. In
Europe other cancer forms are more prevalent, but also here
skin cancer has been clearly identified as one form of cancer
that will become more important in public health terms in the
coming decades. Which may be the main causes of these
differences and of the growing incidence of skin cancer?
Differences in rates could be due to differences in skin color,
amounts of UV exposure both due to environmental and
behavioural factors, and longevity (since cancer is more
common in older groups). Skin cancer incidence may be
increasing due to increased indoor tanning, potentially
increases in the “ozone hole”, perhaps increased sun
exposure and decreased skin protection in some places,
and increasing lifespans. I’m not familiar with cancer rates in
Europe compared to the US. Though I’d be surprised if nonmelanomas aren’t also the most common cancers in Europe.
The incidence of skin cancer is particularly high in young
people and, among these, especially young women. Which
other socio-demographic factors have been demonstrated to
be of importance?
Skin cancer incidence is also high among older men.
Additional risk factors are a personal or family history
of skin cancer, Fitzpatrick Type 1 skin (very fair freckled
skin that often burns in the sun), red hair and blue or
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green eyes, familial atypical multiple mole melanoma
syndrome, many moles, actinic keratoses on the head,
history of indoor tanning, a blistering sunburn before
age 18, multiple blistering sunburns ever, history of organ
transplant, or history of working outdoors full-time for
several years
Darker skinned people like African-Americans or Hispanics
have a lower skin cancer risk with respect to Caucasians.
Could this lead to an underestimation of the risk of developing
melanomas among these population groups? Are there
statistics available?
Yes, these groups tend to underestimate their risk of
melanoma. For example, 65% of African Americans living
in sunny climates report never wearing sunscreen, and
more than 60% of minorities erroneously believe they are
not at risk for skin cancer (Battie, Gohara, et al., 2013).
Also, people with darker skin are more likely to present with
advanced disease and die from melanoma. This is probably
due to various socioeconomic, cultural, educational, and
behavioral factors. Research is lacking on issues related to
social injustice, English proficiency, immigrant status, and
health literacy, however.
Indoor skin tanning by means of UV-emitting devices
represents an important risk factor in the development of
skin cancer. Brazil fully banned the use of these devices for
cosmetic purposes followed by several Australian territories.
In Europe an increasing number of countries, starting from
France, have banned indoor tanning among minors. What do
you think about these measures?
I applaud these countries for protecting the public health
and wish the US would do the same, at least for minors, as
we recommended in our policy statement via the Society
of Behavioral Medicine http://www.sbm.org/UserFiles/file/
IndoorTanning_WebsiteVersion_FINAL.pdf. I believe there is
no valid reason for not banning indoor tanning. Increased
regulation would also help, but this would require greater
funding for enforcement.
Excessive sun tanning has been linked by several studies
to a form of psychiatric addiction associated to endorphin
release during UV exposure. How is actual the state of the
knowledge of this phenomenon? Which strategies can be
used to prevent and cure this kind of addiction?
I believe this topic began to get attention in 2005.
Though the research base is relatively small, there is
compelling evidence supporting the existence of tanning
addiction in a small subset of the population (e.g., 5%
of US college students). The mechanism is not wellunderstood, but endorphin release is likely involved.
I am not aware of any research on the treatment of
tanning addiction. However, it is likely that treatments
for other addictions and psychological disorders such
as cognitive-behavioral therapy, antidepressants, and
anxiolytics could prove helpful. Tanning addiction can be
prevented by not tanning, particularly by avoiding indoor
tanning, in my opinion.
30
Sun exposure has its pros and cons. Recent epidemiological
data suggest that in temperate latitudes sunlight dosedependently increases lifespan both due to the induction
of vitamin D synthesis and the UV induced mobilisation of
nitic oxide from skin stores which may be responsible for the
observed cardiovascular benefits of sunshine. What do you
think? Are we in front of a question of balance?
The evidence for the health benefits of vitamin D is strong,
and the sun produces vitamin D efficiently. However, little
UV is needed for vitamin D synthesis, vitamin D is found
in food, and supplements can be taken. Therefore, most
dermatologists would probably not advise tanning to increase
vitamin D levels. There has been controversy lately over what
constitutes vitamin D deficiency, and what proportion of the
population experiences it. Populations more likely to have
vitamin D deficiency are people with darker skin, shut-ins, and
women who wear burqas.
Which are the main preventive strategies one can adopt to
reduce skin cancer risk?
Limit indoor and outdoor UV exposure especially during
mid-day hours, use shade, wear clothing to cover the skin,
use high-SPF broad-spectrum sunscreen. The Environmental
Working Group provides information about the best and
worst sunscreens http://www.ewg.org/2015sunscreen/.
Researchers of the Centers for Disease Control and
Prevention (CDC) in Atlanta recently evidenced in a study
that most Americans, especially males, don’t use at all
sunscreens to protect themselves from UV radiation. What
has been done and what can be done?
The most effective strategies are comprehensive
multicomponent ones like those conducted in Australia
including long-term media and policy interventions. Few
comprehensive strategies have been attempted in the US.
Skin cancer and education in schools. In Australia and other
southern hemisphere countries, where skin cancer also represents
a serious issue, education-campaigns at school represent
an important tool in raising the conscience of the risks of sun
exposure. Is this a model which should be adopted elsewhere?
Monographic special issue: Sun care - H&PC Today - Household and Personal Care Today - vol. 10(4) - July/August 2015
Yes, ideally. Australia has been very successful in modifying
skin cancer risk and protective behaviour, especially
for schoolchildren. However, cultural, political, size, and
financial barriers often exist in other countries.
Sun protection as a worksite-health promotion strategy for
those workers with an occupational sun exposure. How is the
actual situation? Are there programs ongoing?
There have been successful interventions, for example a
program for highway workers in Iowa and Dr. Karen Glanz’s
national Pool Cool program for lifeguards and other poolgoers. However, I’m not aware of what current programs may
be occurring.
Should people be getting screened for skin cancer?
Skin cancer screening has been controversial in recent
years. There has been disagreement over whether people
should be screened at all, who should be screened,
and how often they should be screened. Some prior
recommendations were to examine one’s own skin monthly
and have a healthcare provider examine one’s skin yearly.
More recent recommendations have been for screening
opportunistically unless at high risk for skin cancer. Though
more recent evidence also suggests greater benefits
from skin cancer screening. The more of the previously
mentioned skin cancer risk factors one has, the more one
should consider skin cancer screening, preferably by a
dermatologist if possible.
Jennifer Linder
PCA SKIN®, Scottsdale, AZ on dermatology and sun protection
Dr. Jennifer Linder, M.D. is a dermatologist and Mohs surgeon, serving as Chief Scientific Officer for skin care and chemical
peel company PCA SKIN®, and running a private practice out of Scottsdale, Arizona. She is a graduate of Washington
University School of Medicine; interned at the University of Pennsylvania; performed her residency at Thomas Jefferson
University; and was a Mohs College Fellow. She holds a clinical faculty position in the Department of Dermatology at the
University of California San Francisco. Dr. Linder is a spokesperson for The Skin Cancer Foundation; and a member of the
American Academy of Dermatology, among others.
Ultraviolet (UV) radiation is associated with serious health
effects. Some are acute but usually reversible, such as
erythema and others are chronic and potentially life
threatening, like premature cutaneous aging, eye damage,
immunosuppression and skin cancer. How to best protect
the skin from these effects?
There are several steps to take in order to prevent the more
serious health effects of over-exposure to UV rays. First, is to
apply a broad spectrum sunscreen with an SPF of at least
30 each day 30 minutes prior to initial exposure to the sun.
If extensive hours are spent outdoors, reapplying a broad
spectrum sunscreen should take place every two hours or
after swimming or perspiring to all sun-exposed skin. Using
a water resistant sunscreen is ideal if excessive sweating or
time spent in water is anticipated.
Which are the best preventive strategies one can adopt
to reduce the incidence of serious adverse effects of UV
exposure?
Avoiding the sun during the hours of 10 a.m. and 4 p.m., when
UVB rays are at their strongest, is one preventative strategy
to adopt right away. If sun exposure during those hours is
unavoidable, wearing protective clothing such as a widebrimmed hat, sunglasses, long sleeves and pants with UPF
rating can further protect the skin.
Exposure to UV radiation is the most preventable risk factor for
skin cancer. Does a “safe” skin-tanning behaviour exist?
There is no such thing as a “safe tan”. When the skin is
exposed to UV rays and the melanogenesis process is
triggered, the risk of damaging the DNA of the skin cell
increases immensely. When the DNA is damaged, repair
enzymes begin preserving the delicate DNA which initiates
melanogenesis and results in tanned skin. Tan skin is actually
impaired, damaged skin, therefore, there is no such thing as a
safe tan from UV rays, natural or through tanning bed use.
Are there demographic differences in skin cancer incidence
in the general population? Which population categories are
most at risk?
Those with light skin, hair and eyes are more at risk of
developing cancerous lesions because their melanin content
is not as densely packed as those with dark skin, hair and
eyes. However, those with darker features are at more risk
of late-stage melanoma diagnoses because it is harder to
detect on their darkly pigmented skin.
Darker skinned people like African-Americans or Hispanics
have a lower skin cancer risk with respect to Caucasians.
Could this lead to an underestimation of the risk of developing
melanomas among these population groups?
It could give these particular populations a false sense of
protection. Although they may not be as likely as Caucasians to
develop cancerous lesions, they are also less likely to detect the
suspicious lesion until late-stages, which can be fatal. In darker
skin, squamous cell carcinomas tends to be more aggressive.
Monographic special issue: Sun care - H&PC Today - Household and Personal Care Today - vol. 10(4) - July/August 2015
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Sun exposure has its pro and contra. Among a series
of favourable health effects, recent epidemiological
data suggest that in temperate latitudes sunlight dosedependently increases lifespan both due to the induction of
vitamin D synthesis and the UV induced mobilisation of nitric
oxide from skin stores, which may be responsible for the
observed cardiovascular benefits of sunshine. Are we in front
of a question of balance?
The debate about the need for unprotected exposure to
UV rays, in order to allow the body to produce vitamin D, is
not likely to reach a consensus. Certainly many people are
deficient in vitamin D, yet supplementation through taking
1000 IU of vitamin D orally is quite easy. It is certainly a
safer option than any level of potentially cancer-causing
UV exposure.
To which extent sunscreens can be considered as efficient
preventive tools against skin cancer? How important is a
correct use of sunscreens?
Other than avoiding the sun altogether, sunscreen is the best
line of defense for protection against skin cancer and proper
use is vital. A broad spectrum sunscreen with an SPF of at
least 30 should be applied to all sun-exposed body parts at
least 30 minutes prior to sun exposure.
Data exist in literature demonstrating that UV filters are
cosmetic ingredients that can induce contact dermatitis or
photo-contact dermatitis upon UV exposure. What do you
think about this fact?
In order to receive The Skin Cancer Foundation’s Seal of
Recommendation in the US, a sun protection product must
go through phototoxicity testing as well as pass an repeat
insult patch test (RIPT) that confirm that the ingredients
in the formulation are not irritating on their own or when
exposed to UV rays. Certainly some individuals may have
allergies or sensitivities to some ingredients in any topical
product, not only sun protection products.
How relevant could be the dietary intake of a series of antioxidant
rich foods to prevent adverse health effects of UV exposure?
Ingesting antioxidants in daily supplements and through diet
is essential for overall health. However, topically applied
antioxidants are the ideal delivery method to guard the skin
from UV rays, pollution and other environmental offenders.
L-ascorbic acid, EGCG from green tea, lilac leaf cell extract
and grape fruit cell extract are potent antioxidants that
have strong scientific evidence supporting their effectiveness
against oxidative damage.
Sun protection and occupational sun exposure of specific
worker categories. Which is the state of the art?
Some careers, like being a commercial airline pilot, lead
to increased levels of sun exposure. Especially because
UV rays travel through glass, anyone who drives a vehicle
for a living or works outdoors will be at increased risk of
the negative effects of UV exposure. These individuals
must take sun protection measures seriously, yet there
isn’t a different strategy for them to take. Reapplication
of sunscreen is of the utmost importance, as well as
regular skin checks with a dermatologist. These should
both be stressed in addition to window tinting in cars or
anywhere possible.
Indoor skin tanning by means of UV-emitting devices
represents an important risk factor in the development of
skin cancer. Brazil fully banned the use of these devices for
cosmetic purposes followed by several Australian territories.
In Europe an increasing number of countries, starting from
France, have banned indoor tanning among minors. What do
you think about these measures?
I fully support these measures and am hopeful that the United
States will adopt these restrictions and ban the use of these
devices. Some states in the U.S. have enacted laws that
restrict the use of indoor tanning devices by minors, which is a
start, but I believe they should be banned altogether.
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Monographic special issue: Sun care - H&PC Today - Household and Personal Care Today - vol. 10(4) - July/August 2015