FROM HEAD TO TOE
SUNSCREEN USAGE AND PHOTOAGING
Jyoti Burruss, MD
S
unscreen usage is highly recom-
mended by all dermatologists for
their patients for many reasons. The
benefits include the prevention of
cosmetic changes to exposed skin
as well as medical concerns.
The cosmetic benefits include de-
creasing damage to skin by ultraviolet (UV)
rays that cause changes that most individuals attribute to “aging.”
It is notable that certain areas of the skin “age” differently. This is
directly related to the amount of UV exposure that has occurred
over the years and not specifically to one’s age. For example, when
sun-exposed skin on the tops of the forearms is compared to non-
sun-exposed skin on the inner forearms, there are usually prominent
variations including more brown spots and texture change as well as
pre-cancers and skin cancers on the sun-exposed areas. These areas
of skin are the exact same age. Other notable changes may include
wrinkles, thinning of the skin and increased fragility (which plays a
role in eventual bruising and easy tearing) of the skin. The bruising
is one of the most bothersome changes to most individuals because
they are highly visible and a reminder of the “extra birthdays” which
have accumulated. Accumulating these birthdays while enjoying life
and one’s favorite outdoor activities is possible without excessively
damaging the skin. But this requires the use of photo-protective
measures including sunscreen and protective clothing.
One medical benefit of protection from the sun includes decreas-
ing painful sunburns which can also increase the risk of common
skin cancers (basal cell and squamous cell carcinoma) and the
potentially deadly cancer known as malignant melanoma. Other
benefits include helping individuals on medications that cause them
to be sensitive to UV exposure or who have underlying diseases
causing increased UV sensitivity.
With the concerns associated with the safety of sunscreens, a
review of the known information is important.
A report released by the Food and Drug Administration in May
2019 1 with a follow-up in January 2020 2 evaluated four UV filters,
(avobenzone, oxybenzone, octocrylene and ecamsule) in three
vehicles (two spray products, a lotion and a cream). In this random-
ized trial, 48 healthy volunteers applied four sunscreen products
containing three of these four chemicals in a manner mimicking
real-life usage. Systemic absorption of avobenzone, oxybenzone and
octocrylene with plasma concentration >0.5 ng/mL was confirmed.
There was also absorption of three additional active ingredients
(homosalate, octisalate and octinoxate) beyond the recommended
limit. Pending further data, dermatologists continue to advise that
patients use sunscreen but emphasize that this use should occur
along with other sun-protection measures (e.g., seeking shade and
wearing Ultraviolet Protection Factor (UPF) rated (see nex page)
clothing, hats and sunglasses). By using other protective measures
and less sunscreen, the ability to enjoy outdoor activity while still
protecting the skin and minimizing excessive exposure to harmful
UV rays is possible. Those who wish to avoid systemic absorption
of chemical sunscreen ingredients may also use sunscreens that
contain only mineral ingredients (e.g., zinc oxide or titanium di-
oxide) which are readily available.
Recommendations for the appropriate use of sunscreens include
the use of a minimum of an SPF 30 sunscreen. Most individuals do
not use this amount of sunscreen, and therefore using a sunscreen
with a higher sun protection factor is appropriate for optimal benefit.
Sunscreens must be applied liberally, repeatedly and to all sun-ex-
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APRIL 2020
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