Sun Protection: What you need to know

What are UVA, UVB, and UVC?
Some people ask me what’s the difference between these UV rays. Then follows the question, “…so which is the bad one?” Well, I always try to give brief and concise answers so here it goes.

Light Spectrum

To answer the first question, UVA (320-400 nm) is associated with photosensitivity and much of photoaging. Photoaging refers to wrinkle formation, skin atrophy, skin fragility, and loss of elasticity. UVB (280-320 nm) causes sunburn and is associated with skin cancers. It is important to note that these adverse effects are not completely or exclusively caused by one type of UV ray. On the other hand, UVC (200-280) is absorbed by the ozone and is not able to reach us. So the answer to the second question is that both UVA and UVB are bad.


How should I protect my skin against UV rays?
The easiest way is to avoid the sun. Walk in the shade, use an umbrella, or wear clothes that cover more.

But if you don’t want to look weird, just wear a sunscreen or sunblock. Sunscreen contains chemicals that absorb the UV rays; these include oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate. Sunblocks contain ‘physical’ agents and block off the UV rays; these include zinc oxide and titanium dioxide.

Like all other drugs or chemicals, adverse effects may occur. One noteworthy adverse effect is hormone disruption seen with some sunscreens with oxybenzone and octylmethoxycinnamate. I suggest sticking to the physical sunblock agents for now.

While on this topic, I have to mention one popular misconception about sun protection. Some people think ‘if the weather is cold, then there’s not much sun, then I don’t need to wear my sunblock.’ This is absolutely not true. Some of you might go hiking, skiing or spend some time up in a mountain cabin during winter and this is the time that you have to wear a sunscreen or sunblock. This is because you’re high up in a mountain, which is closer to the sun and snow reflects up to 85% of UVB. You might also stay out longer because you can’t feel the ‘real’ heat from the sun. This spells out a bad combination of longer and more intense sun exposure for your skin.

Winter sun

What should I look for in a sunscreen or sunblock?
You’ve probably seen many products (other than sunscreen and sunblock) with SPF written on it, including BB and CC creams, foundations, primers, and even lip care products. SPF refers to Sun Protection Factor which mainly reflects the protection against UVB; the number that follows that acronym is derived from a formula. It’s the “minimum erythema dose (MED) through a film of sunscreen divided by MED over unprotected skin”. Pretty simple, eh? It just means that if you use a higher number of SPF, your skin can also handle a higher dose of sun exposure without getting red or burnt. It’s related to the time you can spend under the sun before getting burnt. However, this doesn’t mean you should maximize your sun exposure at the beach. Avoiding sun exposure is still the best way to prevent skin aging and cancer.


Besides checking the SPF number in your products, you should also look for the words ‘broad spectrum’ or ‘PA‘. Broad spectrum means that it protects against both UVA and UVB while PA refers to the Protection Grade of UVA. This system is based on persistent pigment darkening rather than on the redness or erythema on which the SPF is based. The more plus signs you see after it (PA+++), the better.

You should also consider the type of activities you’ll be doing while wearing the product. Are you swimming? Surfing? Will you sweat a lot? Or do you need sun protection only for daily commutes to your office? Whatever your reasons are, keep in mind that some products lasts longer than others and you need to reapply them depending on how long they’ll last. There are water resistant and waterproof types. Water resistant sunscreen or sunblock retains its SPF about 40 min of water immersion while the waterproof one retains its SPF for a whopping 80 minutes of water immersion. Perfect for water sports fanatics!

Other things to consider
Always try out the product in store whenever possible. Check the scent, the consistency, and the color. You don’t want to buy a really expensive cream which leaves a horrible white cast; that would render the product totally unusable for the face. The product should also say “non-sticky” and you should check if it’s actually non-sticky.


So the last but not the least question that probably entered your minds at the start of reading this article is…”what is the best sunscreen or sunblock brand”? All I can say is that I have tried several products in the past and so far I haven’t found the perfect product. There are some close ones though and I’ll write reviews for those so make sure to watch out for my next articles. In the meantime, keep protecting your skin from the sun. ‘Til next time!

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