The Science behind the Sun.
Many of us are stepping happily into Summer, brighter days filled with glorious sunshine ahead.
While we all relish the warmth of the sun’s rays on our skin, we are increasingly mindful of the harmful effects of the sun on our skin. We are bombarded with messages, shelves are full of products and there’s so much reference to ….broad spectrum ….mineral or physical protection...Vitamin D deficiencies….%ages….SPF ratings….
…it’s enough to make your head spin.
But it is essential that we understand what we should be aware of and why, helps make smart sun-safe decisions.
The Science:
Sunlight is made up of different types of ultraviolet radiation that can reach the skin's surface. This includes ultraviolet A (UVA) and ultraviolet B (UVB). UVA rays have a longer wavelength and can penetrate the skin deeper, while UVB tend to affect the more superficial layers of the skin.
When it comes to damaging the skin, both UVA and UVB can contribute to types of sun damage and we are now understanding far more about the reach of the different types of UV light from the sun.
UVB typically is responsible for sunburns. Think B for BURN.
UVA is typically the biggest contributor to ageing skin. Think A for AGEING.
The more powerful UVA can penetrate through clouds, glass and as a result, affects the skin more deeply – if it’s daylight hours, whether you can see the sun or not…it is there and UVA potential for damage is ever present. With UVB it is more variable in strength according to geographical location, season, time of day etc.
We all experience some signs of sun damage right? Photo-ageing It is well documented as a primary contributor to most people’s experience of the signs of age in their skin, whether this is in the form of pigmentation, structural compromise through collagen degradation, dehydration, wrinkles and fine lines or all the above. In worst cases, it can contribute to the formation of skin cancers as well.
SPF
Transparency is at the heart of all we do. We are straight talking about how things work and feel it’s imperative to get more detailed about skin protection.
SPF refers to the amount of protection a product has been measured to achieve against specifically UVB rays.
The number relates to the extension of time you have over your unprotected skin reddening, in other words – if your skin reddens in 20 minutes without protection – SPF 15, would give you 15x longer before reddening occurs. Seems simple enough right?
It is recommended to use a broad-spectrum sunscreen, which refers to protection against UVA and UVB. In terms of whether higher is better, this depends on the amount of product you are applying.
Choosing the right option that suits your need and skin tolerance will determine whether you may prefer a synthetic sunscreen or physical and how to apply it in relation to sun exposure.
Synthetic Protection.
Chemical sunscreen ingredients, absorb UV rays and convert the sun’s radiation into heat energy, synthetic sunscreens absorb the radiation into your skin, which means they need to be applied 20 minutes prior to sun exposure.
Mineral Protection.
Reflect the sun’s rays so work straight away, best for more sensitive skins.
Physical sunscreens (such as zinc oxide and titanium dioxide) deflect and scatter the rays before they penetrate your skin.
But what about the need for Vitamin D?
It is true; the sun provides a source of Vitamin D. However, due to the risks associated with unprotected exposure to the sun’s rays, the American Academy of Dermatology recommends getting Vitamin D from your diet and/or specialist supplements. The recommended dietary allowance for Vitamin D is based on a person receiving little to no sun exposure since the amount of Vitamin D a person receives from the sun is inconsistent.
So, now we know… SPF cannot filter 100% of harmful UV. SPF15 will filter out around 93% of the suns harmful UV, SPF 30 around 97% and SPF 50 around 98% – only 1% difference from SPF30. With so little difference, the key take is:
Use SPF. Everyday.
Use enough.
Re-apply every 2 hours regardless.
It is also important to wear protective clothing that will support your sun protection efforts, avoiding peak hours of sun exposure and seeking shade in the middle of the day.
Go in the sun, enjoy the sun, feel that warmth, breathe fresh air. But be safe a moments risk, a lifetime of regret. Don’t risk it.