Do you slip slop slap every day?
It’s not just pale skins that need daily protection. Whether you are inside or out, your skin is exposed to wavelengths of light that can lead to premature ageing, wrinkles and disordered pigmentation whatever its natural baseline colour.
In this latest blog post our Medical Director, Dr Sarah Boxley, delves into the science behind why you need sun protection even if your skin is naturally dark.
Chances are, if you live in Perth & have one of the lighter skin types, you are probably following the National Guidelines for Sunscreen use and are applying every day, to protect yourself against skin cancer, pigmentation, wrinkles, premature ageing, broken capillaries etc etc. Yay, go you! But, if you are blessed with one of the darker skin types that don’t burn as easily, then it’s possible you don’t bother to use sunscreen on your face everyday. Whilst this is something that I see in my practice all the time, it’s not just me – it’s well documented in the scientific literature that the use of sunscreens and “photoprotective practices” (ie sun avoidance, hats etc) differ a lot between people with light skin (Fitzpatrick types I-II) and those with dark skin (Fitzpatrick types IV-VI)
Many people with the darker skin types (III-IV) don’t regularly use sun protection due to the belief that their naturally dark skin tone is more capable of providing its own protection against sun damage. Whilst it is true that the darker skin types are less likely to experience a red, painful sunburn, this is not the whole story.
There are different sorts of light, and they damage the skin in different ways…..
Different Sorts of Light:
What we know as “sunlight” is the portion of energy emitted by the sun that reaches the Earth’s surface. There are 3 major components: UltraViolet radiation (UVB 290-320nm, UVA 320-400nm), Visible Light (VL 400-700nm) and Infrared radiation.
For decades now we have been well aware of the harmful effects of UV radiation, particularly among those with light skin tones (I-II), whose skin burns with sun exposure. And now more recently, numerous studies have shown the negative impact of Visible Light on skin health, particularly in people with skin of colour (IV-VI)
Visible Light (VL) accounts for 50% of the solar radiation that reaches the earth’s surface, and it can actually cause or exacerbate multiple skin conditions:
- hyperpigmentation
- melasma
- post-inflammatory hyperpigmentation
- uneven skin tone
- photoaging
These effects are seen especially in skin types IV-VI, and whilst patchy/extra pigmentation is not in the same realm of seriousness as skin cancer, it can negatively impact on quality of life and cause real distress over a long period of time.
How does VL effect the skin?
VL generates reactive oxygen and nitrogen species that can contribute to skin damage and pigmentation on the skin. Individuals with dark skin, while naturally better protected against UVB radiation because of the high eumelanin content in their melanocytes, still need additional protection from visible light-induced skin damage. Importantly, for people who have that ability to make excess pigment in places that they don’t necessarily want it, pigment changes caused by VL are more long-lasting and intense than those induced by UVA. There also appears to be a synergy between UV and VL, where VL seems to accentuate the effects of long wavelength UVA. Not good news.
Why have we only just realised this?
The clinical relevance of VL was noticed when studies of women with melasma showed that different types of sunscreen had variable protection from relapse of pigmentation due to differences in their coverage of VL wavelengths. Investigations into LED lights have also shown that the lower range of VL (blue-violet light or approximately 415 nm) is primarily responsible for inducing pigmentation in dark skin types. This wavelength of light is not only found in sunlight but also in the light emitted from computer/phone screens.
So while all skin types should be protected from UV radiation, VL is a concern, especially for individuals with dark skin types. Are you reaching for the sunscreen yet? Hang on – just to make it even more confusing, your sunscreen may not actually be very helpful.
Do sunscreens protect against VL?
Not all of them, no. Why not?
Well, since it is UVB that causes red visible, painful sunburn, the damaging effects of this wavelength was recognised first. This is why sunscreens were originally developed primarily to prevent UVB from penetrating skin. The term “SPF” (Sun Protection Factor) has been used to classify sunscreens since 1978. The SPF of a sunscreen, defined as “the level of sunburn protection” assesses damage caused primarily by UVB and, to a lesser degree, UVA but does not provide information about protective ability against other wavelengths of light.We have known that UVA causes structural damage to skin cells (ie it ages them, rather than burns them) since the late 1960s, but it wasn’t until 2011 that the definition “broad spectrum sunscreen” was changed to incorporate protection against UVA.
So far, nobody has managed to come up with a measure of the protective capacity of sunscreens against VL, and there is no internationally agreed upon rating system for either UVA or VL.
Up to now, photoprotection against VL relies primarily on sun avoidance and use of protective clothing, hats, and glasses.
Chemical UV filters (ie every sunscreen that is not zinc/titanium) do not protect against VL; however, the good news is that barrier sunscreens (zinc or titanium) do. There is also research going on into new ingredients, such as antioxidants and free-radical-quenchers to see if these offer VL protection but there is no definitive proof yet that these are helpful.
So what to do for the best sun protection?
UVA/UVB protection alone is not sufficient for overall skin health, especially in dark skin types. Zinc-based formulas are more effective at protecting against UVA and VL, so particularly for darker skin types these should be used in preference to sunscreens containing only chemical UV filters. The addition of anti-inflammatory agents such as licochalcone A and glycyrrhetinate, may provide additional protection against skin damage.
One major downside to mineral sunscreens, particularly for darker skins, has been their typically opaque, white consistency, which can make them difficult to fully blend in – potentially leaving a white or even purple tone to the skin Thankfully, science has finally caught up with the problem, and the newest generation of mineral sunscreens use micronized technology so that they fully rub into the skin.
Zinc & titanium are also found in mineral makeup, which can be an additional (not alternative) layer of protection against VL. Skincare guru and world renowned dermatologist Dr. Leslie Baumann of @baumanncosmetic has this to say:
Clearly nobody would put that much makeup on! But light coverage of a mineral powder/foundation on top of a broad spectrum sunscreen will give you additional protection. Out personal faves in the clinic? Mineral Whip foundation by @synergieskin or the super handy L brush by @universkin – slip it in your bag and easily touch up during the day.
If you are in front of a computer screen all day, it may be worth fitting the monitor with a simple clip-on blue-light filter.
Sunscreens worth trying for broad spectrum UV + VL protection:
Remember – every skin is different and can tolerate different things. You may need to try a few different ones before you find one that looks, feels and smells right for you. Here are my top five, but there are many more out there: (disclaimer: the first 3 are products we sell in the clinic)
- Uberzinc 50ml RRP $115 An essential daily moisturiser suitable for all skin types, offering broad spectrum protection from sheer 21% zinc in a light natural base with added pure green tea to neutralise free radicals.
- Avocado Zinc 100ml RRP $40 Made locally in Perth, this non-nano zinc oxide formula also contains a blend of skin boosting ingredients including Avocado Oil, Coconut Oil, Vitamin E, Calendula Oil and Kakadu Plum Oil, to soothe & moisturise the skin without weighing it down or leaving it oily. Perfect for sensitive skin types including rosacea, psoriasis and eczema, this natural sunscreen is also suitable for babies, kids and the entire family! Avocado Zinc rubs in clear, goes on sheer and is designed for everyday use on the face, neck and shoulders – it even makes the perfect base for make-up!
- Mother 120ml RRP $42 Mother SPF30 is a hydrating, everyday physical sunscreen using only 9 sustainably sourced and certified organic ingredients. Zinc oxide plus certified organic botanicals, skin loving ingredients including high strength antioxidants to prevent free radical damage
- Dermalogica Invisible Physical Defense 50ml RRP $69 Featuring non-nano Zinc Oxide, this invisible, weightless formula provides added blue light protection and helps soothe away the effects of environmental aggressors. Bio-active Mushroom Complex helps soothe skin, and reduce UV-induced redness and dryness. Antioxidant Green Tea helps defend skin against free radical damage.
- Paula’s Choice Defense Essential Glow 60ml RRP $36 A daytime anti-ageing moisturiser combining all-mineral, broad-spectrum sun protection with licorice, kiwi, argan, niacinamide, vitamin c and other plant and vitamin-derived antioxidants specifically chosen for their ability to defend skin against air pollution and the harmful effects of blue light exposure.
Dr. Sarah Boxley MBBS BSc(hons) MRCGP FRACGP FSCCA FACAM FCPCA
References
Whiteman DC, Neale RE, Aitken J, Gordon L, Green AC, Janda M, Olsen CM, Soyer HP; Sunscreen Summit Policy Group. When to apply sunscreen: a consensus statement for Australia and New Zealand. Aust N Z J Public Health. 2019 Apr;43(2):171-175. doi: 10.1111/1753-6405.12873. Epub 2019 Jan 25. PMID: 30681231.
Rigel DS, Taylor SC, Lim HW, Alexis AF, Armstrong AW, Chiesa Fuxench ZC, Draelos ZD, Hamzavi IH. Photoprotection for skin of all color: Consensus and clinical guidance from an expert panel. J Am Acad Dermatol. 2022 Mar;86(3S):S1-S8. doi: 10.1016/j.jaad.2021.12.019. Epub 2021 Dec 20. PMID: 34942296.
Rigel DS, Lim HW, Draelos ZD, Weber TM, Taylor SC. Photoprotection for all: Current gaps and opportunities. J Am Acad Dermatol. 2022 Mar;86(3S):S18-S26. doi: 10.1016/j.jaad.2021.12.023. Epub 2021 Dec 20. PMID: 34942298.
Mahmoud B.H. Ruvolo E. Hexsel C.L. et al Impact of long-wavelength UVA and visible light on melanocompetent skin. J Invest Dermatol. 2010; 130: 2092-2097
Ma Y. Yoo J History of sunscreen: an updated view. J Cosmet Dermatol. 2021; 20: 1044-1049
Duteil L. Cardot-Leccia N. Queille-Roussel C et al. Differences in visible light-induced pigmentation according to wavelengths: a clinical and histological study in comparison with UVB exposure. Pigment Cell Melanoma Res. 2014; 27: 822-826
Boukari F. Jourdan E. Fontas E et al. Prevention of melasma relapses with sunscreen combining protection against UV and short wavelengths of visible light: a prospective randomized comparative trial. J Am Acad Dermatol. 2015; 72: 189-190.e1