Sun Protection 101
The need-to-know basics of SPF and sunscreen (yes, you need it every day)
Sun protection is a complicated subject. It’s one of the most important parts of any skincare routine but even a small investigation into the topic can leave the mind boggling as you try to interpret labels, ingredients, claims and scientific jargon. Which factor? What about spectrums? Should I be protecting against UVA or UVB rays? (Answer: both!)
Adding to the confusion, in 2020 the American FDA called for further industry research into the safety of some of the active ingredients found in some sunscreens. Worth mentioning: only zinc oxide and titanium dioxide are currently recognised by the FDA as safe (they’re the ones we use!).
So how do you choose the right sunscreen for your skin? Below, we break down the basic need-to-know facts about UV rays, sun exposure and SPF so that you can safely enjoy the sun this summer and beyond.
What’s the Difference Between UVA and UVB Radiation?
When we’re in the sun, we are exposed to two types of ultraviolet (UV) radiation: UVA and UVB. The difference, in a nutshell, is that UVA rays are known as the “ageing” rays and UVB as the “burning” rays. Together, they’re responsible for around 80% of skin ageing.
UVB is only able to penetrate the skin's surface layer (epidermis), causing painful, visible sunburns and dangerous mutations to your DNA. It also damages elastin and collagen, resulting in superficial wrinkling of the skin, changes in pigmentation like dark spots and freckles through melanin-producing melanocytes.
On the other hand, UVA rays may be less powerful than UVB but they’re more prevalent and are more damaging to skin’s appearance.
UVA rays penetrate to the deeper layers of skin, harming both the epidermis and the underlying dermis, the thicker structural support system of the skin, causing pronounced lines, and diminished texture, moisture and firmness. And, because the dermis contains blood vessels, UVA rays can lead to the broken blood vessels often seen on the nose and cheeks.
Plus, UVA radiation also generates reactive oxygen species (both free radical and non-free radical oxygen molecules) that cause oxidative stress, damage cellular DNA as well as impair lipids and proteins.
To summarise: protect your skin from both; they’re bad news.
What on earth is SPF?
Sun Protection Factor (SPF) refers to the capacity of a sunscreen to block UVB radiation, the main cause of sunburn.
The SPF rating system was developed in 1962 and still only applies UVB rays only. The system measures how long a sunscreen will protect your skin from reddening in the sun’s UVB rays, compared to how long it would take for you to burn without any sun protection.
SPF 15 means that only 1/15 of the UVB rays will get through to your skin. So if you’re wearing sunscreen with SPF 15, it will take 15 times longer for skin to redden than it would without it.
SPF ONLY Applies to UVB Radiation
Slapping on any old sunscreen will not necessarily protect you from both kinds of the sun's harmful rays. Only ‘broad-spectrum’ sunscreen protects from both UVA and UVB rays.
In our Exhale Daily Hydrating Nectar SPF30, we use both zinc oxide and titanium dioxide, which form a physical barrier on the skin, acting as a mirror to deflect and scatter the sun’s rays. Together, they provide the toughest broad-spectrum protection against both UVA and UVB rays. And they’re both very gentle on the skin.
SPF 30 is not twice as strong as SPF 15
This one’s a bit tricky to wrap your head around but bear with us…
SPF ratings are based on the proportion of UVA radiation getting through to your skin. So for an SPF 15, 1/15 (7%) of the UVB rays will get through to your skin, meaning that 93% will be blocked. In an SPF 30 sunscreen, 1/30 (3%) of the UVB rays get through to your skin – blocking about 97%.
Here’s a quick reference guide for you:
Yes, You CAN Burn Through Cloud
Don’t let out of sight mean out of mind.
Even on overcast days, 80% of the sun’s rays can pass through clouds, resulting in extensive diffused and reflected UV rays. In fact, you could wind up sunburnt if you neglect to use sun protection just because the sun isn’t playing a starring role in the sky.
Plus, water, sand and snow reflect the sun’s rays onto your skin. So, it's important to apply your sunscreen every two hours or so.
If The Sun Is Up, You Need To Wear Sun Protection. Even Inside.
Most standard glass windows will block UVB light but not the ageing UVA rays. Because of this, it’s important to wear SPF inside your home to prevent premature ageing, as well as inside your car, where your hands are most vulnerable.
Help Your Skin Fight Back
Give your skin the nourishing ingredients it needs to help protect itself from sun damage with a healthy skin barrier. To help mitigate the damage caused by sun exposure, use products that boost moisture and increase hydration, as well as those that are rich in antioxidants that fight free radical damage from UVA and UVB rays.