Is your sunscreen doing its job?
We’ve all been told to wear sunscreen. So as to prevent photo-pigmentation, premature aging, sun damage, etc.
But have you ever wondered whether your sunscreen actually does protect your skin? Or what SPF really means and how your should be applying sunscreen?
Scroll down to discover all that and more!
So what is Ultraviolet (UV) Radiation?
The sun emits energy over a large spectrum of different wavelengths. This includes visible light which you see, infrared radiation which you feel as heat, and ultraviolet (UV) radiation which you could neither see nor feel. UV radiation has a shorter wavelength and higher energy than visible light.
Sunlight is the main source of UV rays. Tanning lamps and beds are also sources of UV rays.
UV rays actually only make up a very small portion of the sun’s rays. But they are the main cause of the sun’s damaging effects on your skin! Over-exposure might cause your skin to age prematurely, eye damage (including cataracts) and skin cancers.
What are the different types of UV rays?
UVA – Think “A” for Aging
Did you know: UVA rays account for up to 95% of the radiation that reach Earth’s surface.
And hence you might have guessed it, you’re exposed to large amounts of UVA throughout your lifetime!
UVA also penetrates your skin more deeply than UVB. And it plays a major role in causing you premature skin aging, wrinkles, pigmentation, sunspots, etc.
UVA rays also goes through clouds and glass – hence its best to have your sunscreen on, even if you’re in your car or behind glass window.
UVB – Think “B” for Burning
UVB is the chief cause of your skin reddening and getting sunburnt. And as it does not penetrate as deeply as UVA, it tends to damage your skin’s more superficial epidermal layers. It also plays a contributory role in skin darkening (tanning) and photoaging.
Unlike UVA rays though, UVB rays do not significantly penetrate glass.
It is the strongest and most deadly of solar rays. Thankfully however, they’re mostly if not all being absorbed by the ozone layer and the atmosphere. So they don’t usually make it to the surface of earth.
What's SPF and what does it mean for your skin?
When it comes to choosing sunscreen, you might have opt for ones with higher SPFs (of up to 130) thinking that it will give you better protection.
But what does the SPF number actually tell you and more importantly, what doesn’t it tell you?
SPF stands for “Sun Protection Factor”. It is a multiplier which tells you how much longer you can remain in the sun without burning when wearing the particular sunscreen.
Basically, an SPF of 30 means that technically, you could be out in the sun 30 times longer before you get sunburned compared to if you went out without sunscreen (as long as you are applying and reapplying it appropriately).
Notice that I only mentioned sunburn and not anything about premature skin aging, wrinkles, sunspots, etc.
Here’s the thing, SPF only tells you about a sunscreens efficacy in filtering out UVB rays.
Essentially, SPF 15 filters about 93% of UVB rays; SPF 30 filters about 97% of UVB rays; and SPF 50 filters about 98% of UV-B rays. The difference between SPF 30 and SPF 50 is only a 1% filtering improvement.
So as you go higher and higher in SPF, the difference in efficacy is actually negligible!
What about protection for UVA rays then?
Your best bet to find out whether your sunscreen provides UVA coverage is to look for the words “broad spectrum“. There isn’t any other metric on the packaging for UVA coverage. Without the words “broad spectrum” your sunscreen likely doesn’t offer coverage from UVA.
What's the right way to apply sunscreen?
Did you know: If you apply too little sunscreen, you would be getting between 50-80% less sun protection than that specified on the product!
So how much is enough?
The standard rule accepted by most dermatologists is to use about 30ml of sunscreen for head-to-toe coverage. This assumes that you’re wearing minimal clothing, (think beach attire, etc). The more of your skin that’s covered by opaque clothing, the less sunscreen you’ll need to apply.
If it’s only for your face, you’ll need about 1/4 teaspoon (3-5 pumps).
Do you have to re-apply every couple of hours?
In short, it depends.
If you’re mostly indoors and out of the sun for the majority of the day, then you don’t really have to re-apply so often. Unless of course if you sweat profusely or washed it off.
On the other hand, if you spend the majority of your day outdoors, then the recommendation is to reapply every two hours, particularly if you’re perspiring or swimming.
What to look for in your sunscreen?
Opt for sunscreens that are at least SPF 15. SPF 30 is however preferable especially in a tropical country like ours. Also don’t forget to look out for the words “broad spectrum“, so that it’ll provide you coverage from both UVA and UVB!
Check out Medik8’s Hydr8 Day 360 Ultra – day moisturiser with broad spectrum sunprotection (SPF 30 and 5 star UVA protection)!
Also contains Vitamin C to enhance UV protection and protects your skin from glycation. Glycation is the largest cause of skin ageing after oxidation.