All About Sunblock - Stability, UV filters, UVA/UVB

I've received a couple of questions regarding sunblock, my favourite sunblock and alcohol in sunblock, so I thought I'd do a slightly more in-depth post on what I know.

I'm an avid believer in sunblock and I've been using sunblock daily since I was 12/13 years old! Start young, they say. If you skip this step, it is rather likely, especially if you stay in sunny sunny Singapore, that you will notice sun pigmentation developing.When hyper pigmentation starts to surface, it is actually due to 10 years of sun damage already! I started my journey with sunblock after avidly reading magazines after magazines. I am probably gonna be the crazy mother in the future who slathers sunblock on my kids.
 

Physical v.s. Chemical Sunscreens

Physical sunscreens or often known as sunblock protects the skin by deflecting/blocking rays. Chemical sunscreens, often known as organic sunscreen, works by ABSORBING or for some, scattering the sun rays.

The UV filters or otherwise, active ingredients in Physical are Titanium Dioxide (TiO2) and Zinc Oxide (ZnO). In Chemical, its a whole long list - Octylcrylene, Avobenzone, Octinoxate, Octisalate, Oxybenzone, Homosalate, Helioplex, 4-MBC, Mexoryl SX and XL, Tinosorb S and M, Uvinul T 1500, Uvinul A Plus.

These UV filters determine a sunscreen's stability. Photostability means the UV filters do not break down when exposed to sunlight. Physical sunscreen's UV filters are all photostable but not all of chemical UV filters are. If it is not, other UV filters can be added to help stabilize it. So, if Physical sunscreen are great, then why not just stick to that? That's cause we are vain  as Physical sunscreens tend to leave a white cast, or a cast back when photos are taken with flash on. Also, they tend to feel heavier and oily. Physical sunscreens must often be reapplied to be more effective.

Chemical sunscreen are colorless and usually runny which indicates a lighter texture and feel to the skin, which people prefer. 

Titanium Dioxide protects against UVB rays while Zinc Oxide protects against entire spectrum of both UVA and UVB rays. It will start protection upon application. However, the Titanium Dioxide in Physical sunscreens can cause skin issues like breakouts for some people. Zinc Oxide is a naturally safe product for most skins and can even be found as an ingredient in creams treating rash.

For chemical sunscreen, it offers coverage against UVA/UVB but the range of protection depends on the UV filters and its stability. For effective protection, it is normally advised to wait 20 minutes after application before you step out into the sun. Chemical filters tend to also cause allergic reactions in some people as the filters might irritate the skin.

UVA rays are the one that cause wrinkles and skin-ageing effects whilst UVB rays has strong links to malignant melanoma and carcinoma risks.

How many +???

PA ranking refers to the amount of protection the sunscreen offers from UVA rays while SPF ranks protection from UVB rays. 

PA rankings are listed with the number of '+'. The more '+' symbols, the more protection from UVA rays - the rays that may cause longterm skin damage and age the skin overtime.

Alcohol as an ingredient

I got really affected by the smell of alcohol of certain sunblocks I was using and after googling, realized that the top 3 ingredients contain alcohol, which means it contains SHITLOAD of alcohol! 

Alcohol is found in most sunblock cause it provides that cooling, drier sensation that most people prefer, rather than the thick heavy cream. I personally don't like alcohol as an ingredient in skincare. However it's really not 100% possible to avoid it lah. I just prefer to minimize the amount build up overtime. 

Alcohol comes in different forms and the most damaging one is normally labelled as Alcohol Denat. There are other categories of alcohol; namely fatty alcohol in skincare ingredients that are NOT harmful, and in fact can be beneficial or necessary

With regular exposure to alcohol-based products, cleansing becomes a damaging ordeal—skin is no longer able to keep water and cleansing agents from penetrating into it, thus further eroding the skin’s barrier.

For those with oily skin, alcohol can stimulate oil production at the base of the pore, so the immediate de-greasing effect is eventually counteracted by oily skin producing even more oil!
— Paula's Choice

If u see drugstore sunblocks that is termed watery or light or if it comes in gel-like texture, check the ingredients and u should see Alcohol Denat as one of its first 3 ingredients.
The alternative to those 'light'/gel sunblocks are the heavier cream ones. Those that people don't like cause it feels heavy/oily. 
 

 Hada Labo Air Aqua UV SPF 50 +++

Hada Labo Air Aqua UV SPF 50 +++

This is my absolute favorite sunblock. I've tried SO MANY brands over the past 13 years and this is hands-down my favorite sunblock. 

Ingredients:

Water, Ethylhexyl Methoxycinnamate, Polyglycerin-10, Phenylbenzimidazole Sulfonic Acid, Dimethicone, Water/Tremella Fuciformis (Mushroom) Extract, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Diethylhexyl Carbonate, Polymethyl Methacrylate, Butylene Glycol, Arachidyl Alcohol/Behenyl Alcohol/Arachidyl Glucoside, Ethylhexyl Triazone, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Dimethicone/Dimethiconol, Sodium Hydroxide, Polysorbate 60, Water/Polyquaternium-51, Phenoxyethanol, Xanthan Gum/Hectorite/Cellulose, Xanthan Gum, Methylparaben, 3-O-Ethyl Ascorbic Acid, Tremella Fuciformis Polysaccharide, Citrus Aurantium Bergamia (Bergamot) Fruit Oil, Propylparaben, Disodium EDTA, Hydrolyzed Lupine Protein, Water/Butylene Glycol/Nephelium Longana Seed Extract, Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Resveratrol (Source: CosDNA )

This sunblock does not contain alcohol. It is also ph-balanced as it includes Sodium hydroxide which is used for adjusting pH. Some other brands might use triethanolamine to do that but that actually has risks of carcinogenicity! It is also free of animal-derivative ingredients, is alcohol free, colorant-free and mineral oil-free! 

I love that is has an incredibly light and watery texture but that also indicates it is a chemical sunscreen. Therefore, do a patch test first if you are sensitive to chemical active filters! 

Spray-on sunblocks generally contain alcohol so I avoid using that on my face. However, I'm not too fussy about using it on my body. However, research has shown that if people tend to wear less sunscreen when using spray versions. But any kinda sunscreen is better than none! 
However, any kind of sunscreen contain foreign ingredients so do your best not to apply it directly onto bare skin. Always make sure you have at least moisturizer on first~ and remember to double cleanse at the end of the day, even if u only wear sunblock and no makeup!
 

In the day when I am out, I can't possibly be removing my makeup and reapplying my sunblock so I like to carry a translucent compact that provides SPF! This allows me to touch up on the go!

And this concludes a looooong post on sunblock! Talk to you all soon! Pea xo