How Sunscreens Protect your Skin: Understanding UVA and UVB Rays
We all need protection from the sun’s ultraviolet radiation (UV). This includes UVA and UVB wavelengths.
Prolonged exposure can damage DNA, cause premature skin aging (the leading cause of wrinkles, fine lines, rubbery skin, loss of skin elasticity, degeneration of collagen, etc.), and promote the development of potentially deadly skin cancer. The scariest thing about this is you usually don’t see any of this until it’s too late.
When it comes to skin protection, prevention is the key.
It is recommended to use sunscreen daily because unless you live in a cave, you’re always at risk. Pay special attention as well when you’re exposed for prolonged periods like at the beach or among snow when the reflectivity of water and ice amplifies the sun’s rays.
These types are categorized according to the depth of penetration of their wavelength.
- UVA – Long length UVA rays that penetrates deep into the skin. Contributes to the development of skin cancer. Accelerates photoaging. Blocked by Broad Spectrum Protection.
- UVB – Medium length rays that reach the skin’s superficial layers. The primary cause of sunburn and skin redness. Contributes to hyperpigmentation and signs of photoaging. Blocked by SPF (Sun Protection Factor).
Types of Sun Protection: Chemical Sunscreen vs. Physical Sunblock
There’s always been a continuous debate on which type of sunscreen is the best. Do you use a physical sunblock or a chemical sunscreen? Which one should you choose? What are the pros and cons?
When people look at sunscreens, most people zero in on the SPF rating and assume that the higher it is, the more effective it will be. Because surely, an SPF 60 is twice as better than an SPF 30 right? The answer: Not necessarily.
SPF is only a measure of UVB burn time. It is a non-linear scale of how much UVB radiation is needed to give protected skin sunburn. It does not measure UVA.
While the premise that higher is better, the minimum requirement of SPF 15 already blocks 93% of UVB rays. You get a slight increase as you jump to SPF 30 blocking 97% of UVB, and SPF 50 blocking 98%.
SPF is based on the quality of sun exposure. So how much time you have before you start to burn really depends on a long list of factors including genetics, and where/where/how you spend time under the sun. (PSA: Children under 6 months should have almost no sun exposure as their protective mechanisms have not developed yet and will only likely absorb the sunscreen.)
To help you decide which one is most suited for your skin, let’s take a step back and understand the two types of sunscreens:
- Mineral or Physical Sunscreens – deflects UV rays with inorganic blockers like zinc oxide or titanium dioxide acting as a physical barrier
- PROS: Once you put it on, it will start to take effect immediately. Usually has higher UVA protection, which also protects your collagen. As it only sits on the skin and is not absorbed, there are fewer chances of skin irritation and potentially harmful effects. If you plan on swimming in the ocean, this is better for the environment as they don’t damage coral reefs.
- CONS: More expensive. Usually harder to apply and leaves a telltale sheen of white on the skin.
- Chemical Sunscreens – uses carbon-based compounds to absorb UV photons that are then harmlessly dissipated as heat.
- PROS: Cheaper alternative. More transparent when applied.
- CONS: 95% of products have less UVA protection compared to physical sunscreens. You need to wait at least 15-20 minutes for the sunscreen to absorb and start to take effect. Higher potential for skin irritation or allergic reactions. Carbon chemicals can harm marine life and coral reefs. Photosensitive—they deteriorate more quickly as their ability to absorb the sun’s rays diminishes.
- Hybrid Sunscreens – formulations that combine both physical and chemical compounds.
Natural Aging vs. Premature Skin Aging from Sun Damage
A picture paints a thousand words. So instead of waxing lectures about the importance of using sunscreen (a PSA which I’m sure you’ve heard a million times), I’ll let the results speak for themselves. These are visual examples of accelerated skin aging as a result of long-term sun damage.
For 28 years, this truck driver has had his left side exposed to UVA rays through his window glass–whereas his right side was relatively normal. He has photodamage on the left side of this face, resulting in abnormal thickening and wrinkling of the skin, destruction of elastic fibers, multiple open comedones, and nodular elastosis (cysts and comedone formation).
Choosing the Right Sunscreens for Oily and Acne-Prone Skin: What to Look For
Remember, skincare is as individualized as you are. We all have different needs depending on our lifestyle and skin conditions.
Right now, there are thousands of options in the market. Finding not only the best performing sunscreen but one that is also the right fit for you can be a challenge.
And with your skin health on the line, you should expect only the best.
These are what you should consider when choosing sunscreens for oily and acne-prone skin:
- Application method – this can impact the amount of coverage and actual protection you get, as well as the likelihood that you’ll use it.
- Lotions – Cheaper than sprays. Better chances of getting enough product per application as you can actually measure it. Can be more time consuming to work into the skin.
- Sprays – Very convenient to put on, especially when you’re wet. The biggest issue is that most people don’t apply a thick enough layer to get full protection. You’ll need several coats to get enough every time. There’s also the possible health risks of inhaling some of the spray cloud.
- Key Sun Protection – it should have broad spectrum coverage and have minimum SPF 30 for full UVA and UVB protection.
- Active Ingredients – This determines the type of sunscreen it is. Physical or mineral sunscreens are top tier, while hybrid and chemical sunscreens are your more affordable options.
- Cosmetic Elegance – It is crucial that you like the feel, consistency, texture, tint, and finish of the product on your skin.
You should like your sunscreen enough that putting it on would be an
enjoyable experience—not a task. No one wants to put on a product that
feels off–even if it’s for our own protection! Loving a product is one of the keys to a fully effective skincare regimen.
For oily skin that may be acne-prone, dermatologists recommend using a non-comedogenic sunscreen with fluid, lightweight formulas that have a matte finish so they control oil and don’t clog the pores. If you also have sensitive skin, it should be hypoallergenic and fragrance-free as well.Another technical factor in cosmetic elegance is: the smaller the particles are, the less reflection of light you get (white cast). A great sunscreen should blend flawlessly into your skin for an invisible protection.
How To Make Sunscreen Work Under Makeup
No one wants to look like a melted geisha in the middle of summer. One of the seemingly more difficult tasks of working with sunscreen is how to make it blend flawlessly with your makeup (and stay there!). Mishaps may include: a white cast that ends up looking like an irl insta filter gone wrong, the sunscreen making your makeup slide off, etc.
Here are a few tips and tricks to applying sunscreen like a pro.
The Skin Cancer Foundation’s Seal of Recommendation
Granted to brands that have been tested by and have met the rigorous standards of the Skin Cancer Foundation’s photobiology experts. Having this seal means the product has solid scientific data showing that it can sufficiently and safely prevent sun damage to the skin.
The Seal of Recommendation for sunscreens has two categories:
- Daily Use Seal – for sunscreens that are used to protect the skin from incidental exposures over short periods of time.
- Active Seal – intended to protect the skin from extended sun exposure, e.g. sports, outdoor activities. Products under this seal have higher SPFs, UVA protection, and requires it to be water-resistant.
Regarding which sunscreen is ultimately better–once you’ve ticked all the boxes above, it all comes down to its compatibility to your skin.