The ultimate sunscreen guide: what’s the deal with SPF and chemical vs physical sunblocks anyway?

Hands up if you’re guilty of starting a sunscreen routine too late, or if you’ve (gasp!) never found a need for it. As much as it pains me to admit, I was once doubtful of this skinsaver and have paid the price for it when an obvious age spot crept up on me in my early twenties. Don’t learn the hard way – whether you’re a skincare diehard or not, it’s time to take this wonder product seriously. Not only does it decrease the risk of skin cancer, it also helps to prevent premature ageing, pigmentation and blotchiness. But if you’re baffled by the many labels, don’t fret; we break down everything you need to know about sunscreen, including SPF, PA and the difference between physical and chemical sunblocks.

Sunscreen 101

Sunscreens, sunblocks and suntan lotions
First of all, avoid anything called ‘suntan lotion’ like the plague – these have a poor SPF (that’s Sun Protection Factor), and are oils, which don’t shield you from the sun. Both sunscreens and sunblocks are good sun protectants; expect the latter to have a thicker and chalky consistency due to the use of titanium oxide or zinc oxide as the active ingredients.  

How high should your SPF be?
SPF measures how well a sunscreen protects you from UVB rays (the cause of sunburn). A minimum of SPF30 is best recommended as it blocks 97% of UV-B rays, though SPF50 is ideal as it blocks 98% of UVB rays. Any higher is said to be false advertising.

Look for broad spectrum
Most sunscreens only protect you from UVB rays – ideally, it should also shield you from UVA rays (these penetrate deep into skin and can cause premature aging).

What is PA?
Simply put, PA indicates the level of protection from UVA rays. This is based on the Persistent Pigmentation Darkening Test (PPD), which measures how much UVA skin can be exposed to before darkening. The more plus signs on your PA (this ranges from PA+ to PA+++), the more protection you’ll receive. It’s the reason why Korean sunscreens are regarded as more effective – they often come with these labels.

What’s the deal with chemical or physical blockers?
It’s not just the the topic of SPF that’s rucking up controversy. A major topic of debate is the difference between chemical and physical sunscreens. As its name suggests, chemical sunscreens contain oxybenzone, octylcrylen, avobenzone and octinoxate. These work by absorbing UV rays – they enter skin, are absorbed and are released as heat.

Physical sunscreens, on the other hand, contain active mineral ingredients like titanium dioxide or zinc oxide. They work as reflectors to deflect UV rays from entering the skin.

The case for chemical blockers:
It’s hard to say what’s better for you, as the effects of each are different on each skin type. Chemical sunscreens are the popular option on the market. These are thinner in consistency, and blend easily on skin, sitting well under makeup. These formulas are also receptive to the inclusion of other ingredients, like hyaluronic acid, to moisturise skin. It also does not give the notorious white cast of zinc-based sunscreens.

But, as it absorbs UV rays, skin can become overheated, which results in irritation or worsening of dark spots. It’s even said to penetrate into your bloodstream – something to think about if you’re not fond of chemicals lingering in your body.

Chemical sunscreens are also not recommended for water sports; Hawaii has banned oxybenzone and octinoxate beginning 2021 as these are harmful to corals, and contribute to coral bleaching.

The case for physical blockers:
With natural ingredients and ability to simply deflect UV rays without absorbing, physical sunscreens are gentler on the skin and are less likely to cause skin irritation. The ingredients of zinc oxide and titanium dioxide are also naturally broad spectrum, protecting you from UVA and UVB rays. Unfortunately, they don’t spread as easily, and may leave a white cast on skin. But with the beauty industry working fast, physical sunscreens already exist in the market that are as light and blendable as moisturiser.

Application
Apply at the last stage of your skincare routine and you’ll find that it could even work well as a primer. Chemical sunscreens should be applied 20 minutes before stepping outside, while physical ones are absorbed immediately. It’s recommended for you to reapply every two hours if you’re outdoors. Most people (myself included) don’t apply enough as two tablespoons per application is required for optimal protection.

Physical sunblocks 

Bema Cosmetici Solartea High Protection Sun Cream SPF50
This natural product works a treat for plenty of skin types. It’s suitable for sensitive skin, and those with very fair skin tones. Its mineral filters protect the skin from UVA and UVB rays, without blocking natural perspiration. It’s also rich in antioxidants, concentrated Vitamin C and minerals to boost skin hydration and health.
$50, available online at Aldha and 61 Emerald Hill.

La Roche-Posay Anthelios XL SPF 50+ Tinted Fluid Extra Light
A firm favourite amongst sunscreen devotees, this seriously lightweight sunscreen coats skin with SPF 50+ protection, thanks to its combination of Mexoplex (a blend of ingredients which gives increased UVA/UVB protection and does not cause skin irritation) and anti-oxidising thermal spring water. Fragrance and paraben-free, it helps to prevent sun-induced pigment spots.
$46.90, available from Guardian and Watsons stores islandwide

First Aid Beauty Ultra Repair Pure Mineral Sunscreen Moisturiser SPF40
This is one heck of a powerful sunscreen. For starters, it contains colloidal oatmeal and butters and oils to nourish skin. It’s also got a botanically rich antioxidant booster to combat environmental aggressors. Despite the physical blockers in its formula, it’s got a lightweight texture that absorbs with zero white cast while giving skin high-level UVA and UVB protection
$48, available at Sephora  

Just Herbs No Sun Jojoba-Wheatgerm Moisturising Sun Protection Gel
This Goop-approved sunscreen does double duty: it moisturises and protects. Made from jojoba, wheatgerm and grape seed oil, it hydrates and heals skin while providing protection from UV rays. It even relieves clogged pores and defends against skin ageing.
$17, available at Sephora

Face SPF 30 Matte Finish Cucumber
If you’ve ever wanted your face to smell like cucumbers, this is it. The antioxidant-infused formula has a light cucumber scent, and gives skin UVA/UVB as well as environmental protection. Bonus: calming Evening Primrose and flaxseed Oils gives skin abundant Omega-3 and Gamma-Linolenic Acid to boost elasticity and help skin retain moisture.
$65, shop online or available at The Naturally Better Company, Millenia Walk #02-46
9 Raffles Boulevard, Singapore 039596

Chemical sunscreens 

SK-II Atmosphere Airy Light UV Cream SPF50+
This sunscreen sure does live up to its name – it’s incredibly airy and light, and dries to a silky, soft matte finish.. It even goes above and beyond its SPF50 protection, as it combats infrared and pollutants.  Plus, it contain the brand’s powerful signature ingredient of Pitera to lighten dark spots and retain moisture.
$115, available at SK-II boutiques  

Aesop Protective Lotion SPF30
The heavens must have heard our cries when we longed for an Aesop sunscreen. The hydrator is packed full of antioxidants, thanks to green tea and tocopherol (Vitamin E) and skin-soothing panthenol. Much like the rest of its range, it smells like a spa, and has a lightweight, non-sticky texture.
$80, available at Aesop Signature stores

Kiehl’s Ultra Light Daily UV Defense SPF 50 PA+++
As someone with oily skin, I research the heck out of sunscreens, as plenty in the market still have a greasy residue, and leave my skin even shinier than before. This Kiehl’s bestseller is extremely lightweight, and feels like you’re wearing nothing even after you’ve got all your skincare on. It’s also great for sensitive skin as it’s fragrance-free, non-comodogenic and contains Rosa Gallica to soothe skin.
$55, Available from Kiehl’s stores, multiple locations including ION Orchard. 

Neutrogena Ultra Sheer Dry-Touch Sunscreen SPF50++
No surprises why Neutrogena’s Ultra Sheer Sunscreen has such a huge fanbase: it absorbs instantly, and leaves skin with an invisible finish. Best of all, it’s oil free, and leaves skin with a matte finish – perfect for everyday wear. Take your pick of sun protection from SPF 30 to 100.
 $14.58  for 88ml, Available from Iherb, Guardian and Watsons stores islandwide

Biore UV Perfect Face Milk SPF50++/PA++++
I can personally vouch for this – this Biore bestseller completely overturned all my misconceptions about sunscreens. It mattifies the oiliest of skin thanks to its sebum-absorbing powder, and applies lightweight despite its ominous creamy texture.
$15.60, Available from Guardian and Watsons stores islandwide

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