Sunscreen 101

One of my life regrets is not having a skincare regime until lately. I was never disciplined enough to keep up with any kind of routine and the longest I've ever committed to was for less than 2 weeks! 

Skincare wasn't my priority because I'm didn't have prominent issues (besides the occasional time-of-the-month zits) with my average complexion. Since I have oily to combination skin, toning and moisturizing after cleansing felt negligible as my face doesn't dry out. Hence, owning a sunscreen was the last thing I ever thought of. I was more of a makeup junkie who easily owns more than 20 lipsticks and was obsessed with different shades of nude, red, and pink. 

Being a beach-lover and getting closer to the age of 27, my female friends chided me for neglecting sun protection for years. I didn't budge until now as my persisting comedogenic acne refused to back down despite improving my diet and increasing my daily water intake.  After reading up on skincare facts and ingredients, I realized sunscreen is one of the most important products for skin anti-aging and damage. I believe the lack of sunscreen usage contributed significantly to a few problems I faced over the years. Like most starters, I was stuck with the mind-boggling variety of sunscreens available in the market. So after an entire day of research, here's some essential knowledge I've found: 

1. Sunscreen VS Sunblock

Most of us probably grew up hearing "sunblock lotion" more than sunscreen. However, you might be surprised to be unable to find products with the label "sunblock" these days. Years ago, U.S and Europe authorities have banned the term "sunblock" in product labeling to prevent consumers from overestimating the effectiveness. Instead of comparing sunscreen and sunblocks, I'll talk about the types of sunscreen.

How do they work?

Today, sunscreens are simply classified into two categories: chemical and physical. The main difference between these two products is the primary active ingredients. For physical sunscreen, the filters are made up of mineral zinc oxide and titanium oxide. Whereas for chemical sunscreen, some of the common filters are avobenzone, ecamsule (also known as Mexoryl SX, patented by L'oreal), octocrylene, oxybenzone and more.

These days, there are many sophisticated sunscreen formulas and ingredients that are able to protect against both UVA/UVB. Sometimes, a product may be a hybrid of both chemical and mineral filters too. Sunscreens offering both UVA and UVB protection are commonly called as broad-spectrum protection. The best bet is to check the ingredients list to know what you're getting instead of just relying on what is printed on the front.

2. Types of UV Rays

The three main types of UV rays produced by sunlight are: 

  • UVA: Longest wavelengths, transmitted through the atmosphere, penetrate the middle layer of skin (the dermis)

  • UVB: Short wavelengths, transmitted through the atmosphere, some absorbed by Earth's ozone layer, reaches the outer layer of skin (the epidermis)

  • UVC: Shortest wavelengths, all absorbed by Earth's ozone layer

3. UV Rays and Their Damage:

Mostly, we are in contact with UVA and a small amount of UVB.

  • UVA rays age skin cells and can damage their DNA. This is related to wrinkles, sagginess, photoaging, damage to cells producing collagen and elastin and contribute to skin cancer. Majority of the tanning beds emit a large amount of UVA, which has been found to increase skin cancer risk. 

  • UVB rays have slightly more energy than UVA rays. They stimulate the production of melanin and cells to produce thicker epidermis. It can damage skin cells' DNA directly, and cause sunburns and redness. They are a more potent cause of certain types of skin cancer. 

4. What is SPF:

SPF stands for sun protection factor which is used to indicate how much protection the product offers and how long you can stay under the sun before getting a sunburn. The amount of SPF needed varies for each individual. If you get sunburns quickly and will be outdoors for long, go for higher SPF products.

For example: If you usually get sunburn after 10 minutes, an SPF 20 product will allow prevent you from getting a sunburn for about 200 minutes (SPF x time to get sunburned). Of course, that depends on your activity as sunscreen may be removed in the process. The amount of SPF we need is also dependent on how much melanin we have or how darkly pigmented our skin is.

5. High SPF Misperception:

Higher SPF products with rating 100+ do not mean they can protect us 100% from the rays. The absorption of the UV rays does not increase exponentially in correspondence with SPF too. An SPF 15 sunscreen absorbs 93.3% of UVB rays, while an SPF 30 product absorbs 96.7%. It is only a difference of 3.4%, not essentially double the amount. A high SPF product is recommended if you intend to wear lesser of the product as SPF is measured at 2mg/cm2. Spreading an insufficient amount of product over your face will not give you the stated amount of SPF which brings us to the next point.

6. SPF in Cosmetics:

Did you think that your M.A.C. liquid foundation with SPF 30 was sufficient? Fret not, I totally thought the same too. The problem is we'll probably look like a geisha in order to achieve that amount of SPF through a liquid foundation. According to Michelle from Lab Muffin Beauty Science (watch her Youtube video above), to achieve the SPF indicated on your foundation, you'll need 1.2 grams of powder or 1.2 ml of liquid foundation (which is heck load!). Based on an SPF 30 makeup product and several calculations, an average standard usage of powder only provided SPF 1.7 and SPF 5 for liquid foundation. Therefore, you do need a separate sunscreen to protect your skin.

7. Sunscreen Reapplication:

It's common for people to assume one application would last us the entire day. Depending on your activity, sunscreen can wear off easily and chemical sunscreen deteriorates during the process of converting UV rays into heat. SPF value drops dramatically when it is exposed to water, sweat or oil. Pretty much explains why most sunscreen products' give the directions of reapplication at a frequent interval to get the maximum protection. Just think that sunscreen runs like how our makeup would after a long day!

Lastly, I would like to highlight that you might want to avoid the ingredient oxybenzone as research over the past years has shown that it kills coral reefs. The chemical oxybenzone damages the corals' DNA which cause harmful mutations. Oxybenzone can kill at least seven different types of coral, and it doesn't take much to do it: one drop in the amount of water equivalent to 6.5 Olympic sized swimming pools is enough to be deadly. If you are an avid diver, this is definitely worth noting.

I hope this sunscreen knowledge is helpful for people who have overlooked sun protection like me. Wearing sunscreen is one of the basic essential steps to score a young looking skin in years to come! Right now, I am on Kiehl's Ultra Light Daily UV Defense which is a broad-spectrum protection product with SPF 50. Picked it because I like its light and smooth texture when I tried out the sample. It didn't give me that white cast which Korean brand Clio and Banana Boat did. Also, it wasn't as sticky or oily as the past drugstore brands I had used. However, do note that this is subjective to individual's skin type. Till then!


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